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1
Tonello, Mark A. "Population structure and dynamics of alewives and spottail shiners in Indiana waters of Lake Michigan, 1984-1996." Virtual Press, 1997. http://liblink.bsu.edu/uhtbin/catkey/1048392.
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The population dynamics of alewives Alosa pseudoharengus and spottail shiners Notropis hudsonius were investigated in Indiana waters of Lake Michigan from 1984-1996. Insights to population dynamics of both species were found by applying age and growth information to length-frequency distributions of index trawl catches within and between years. Both alewife and spottail shiner populations showed general increasing trends over the period, reaching peak levels in 1996. Interaction potential was examined for alewives, spottail shiners, and the yellow perch Perca flavescens, another important nearshore species. Trends in relative catches of these species were correlated to provide insight to possible interactions. There appears to be negative relationships between alewife and yellow perch populations, as well as between yellow perch and spottail shiner populations. No relationships were found between alewife and spottail shiner populations.Department of Biology
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Mueller, Robert F. Jr. "Fish assemblages in the Wabash River : responses to substrate variation in field collections and artifical streams." Virtual Press, 2008. http://liblink.bsu.edu/uhtbin/catkey/1391677.
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Relationships between fish assemblage composition and substrate variation is poorly understood in large rivers. Information on fishes occurrence and behavior and substrate variation were examined in field observations for the Middle Wabash River and fine scale artificial streams experiments. The results from field observations suggested strong concordance for variation in abundance of fishes with habitat variation among sites, resulting in a longitudinal river gradient as dominant in the Middle Wabash River. In addition, shifts in fish behavior within artificial stream experiments demonstrated that species-specific habitat selection behaviors were influenced by interactions within a fish assemblage. The combination of artificial stream experiments and field observations can identify fine scale trends that bioassessment surveys cannot tease apart, and highlighting the need to examine species-habitat relationships at more than one scale.Department of Biology
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McKeag, Kevin J. "An evaluation of the potential forage fish populations in Indiana waters of Lake Michigan, 1973 vs. 1984-86." Virtual Press, 1987. http://liblink.bsu.edu/uhtbin/catkey/483384.
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The potential near-shore forage fish populations were investigated by bottom trawling during the months of June through August of 1984-86 in Lake Michigan, near Michigan City, Indiana. Data were collected on the six moat common species including: yellow perch (Perca flavescens); alewife (Aloes pseudoharenqus); rainbow smelt(Osmerus mordax); bloater (Coreaonus,hovi); spottail shiner (Notroois hudsonius); and trout-perch (Perconsis omiscomavcus). Results of the 1984-86 sampling period were compared with data for 1973 in an attempt to document changes in population density, species composition, annual catch, seasonal abundance, and population structure.The total trawl catch for all species increased nearly seven-fold since 1973 even though sample methods and collection effort were unchanged. A dramatic increase in yellow perch abundance was primarily responsible for the elevated levels sampled for all species from 1984-86.The species composition of the catch shifted since 1973. In 1973, spottail shiners were the most abundant species (41%) and trout-perch and alewives were the next most abundant species comprising 20% and 17% of the catch, respectively. Yellow perch, which comprised only 12% of the catch in 1973, increased to 81% of the catch in 1986. Bloater also showed a great increase in relative importance since 1973 when they were rare in the catch. Other species, including alewife, were relatively minor components of the total catch each year from 1984-86. The trawl catch results revealed that alewife and trout-perch declined 71% and 87%, respectively, comparing 1973 with 1984-86. During the same period, yellow perch increased 72-fold and bloater over 3000-fold. By comparison, the spottail shiner population was stable with no long-term changes, but rainbow smelt populations fluctuated widely.Seasonal abundance of adult fish (age I or older) generally decreased from June to August for each fish species and year sampled with the exception of yellow perch which peaked in July of 1973, and in August of 1985-86. Young-of-the-year fish were generally captured in late July and August.Population structure changes were evaluated by examining pooled length-frequency data. Yellow perch length-frequency distributions indicated that strong year classes were produced every year from 1983 to 1986. The 1985 year class was well over twice as large as any of the other years sampled. Spottail shiner and rainbow smelt length-frequency distributions remained approximately stable since 1973, while alewife length-frequency distributions fluctuated annually. Capture of bloaters was almost entirely limited to June, and consisted primarily of age I+ fish in 1984-86.These results reveal significant changes have occurred in the potential near-shore forage fish populations in Indiana waters of Lake Michigan since the early 1970's. Although several factors may be involved in the shifts noted, the major contributing factor is likely predator-prey interactions as a result of salmonid predator density.
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Tolentino, Scott A. "An analysis of the relative weight (Wr) of yellow perch from Indiana waters of Lake Michigan, 1984-91." Virtual Press, 1992. http://liblink.bsu.edu/uhtbin/catkey/834610.
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Relative weight (Wr) of yellow perch (Perca flavescens) was evaluated for fish collected from the Indiana waters of Lake Michigan in June, July and August of 1976 and 1984-1991. Computation of Wr was completed for individual fish in 20 mm intervals over the size range from 100-219 mm using Wr = (W/Ws) 100 where W=weight of a fish in grams and Ws=standard weight for a fish of the same length. Length was highly correlated with weight in all years for males, females and sexes combined (r=0.97-0.99). Distributions of predicted weights for fish at 130 mm and 250 mm were at or near modes of the populations used to construct the Ws equation for yellow perch. Relative weights consistently decreased with increasing size in all years for males, females and sexes combined. Using 1976 length-weight data when the yellow perch population was sparse and fast growing as a standard (100%) for comparison, relative condition factors (Q) increased with increasing size in some years and decreased with increasing size in others for males females and sexes combined and it did not appear to be length dependent. When comparing Wr at 100 mm and 200 mm by sex and month, f hales had higher Wr than males at 100 mm in seven of nine years in June, six of nine years in July and only four of nine years in August. Female fish also had higher Wr than males at 200 mm in eight of nine years in June and July and six of nine years in August. There appeared to be no consistent pattern or trend of Wr increasing or decreasing by month for males, females or sexes combined. When Kn was evaluated for 100 mm and 200 mm fish by sex and year, male fish had higher Kn than females at 100 mm in all eight years. Male and female fish at 200 mm were more similar; male fish had higher Kn in three years, lower Kn in three years and equal Kn in two years. No relationships were found at 200 mm comparing Wr or Kn and CPE (quality/ h) for males (r=0.43; r=0.42), females (r=0.12; r=0.13) or sexes combined (r=0.28; r=0.22). Simple linear correlations of proportional stock density (PSD) with Wr and Kn revealed relative weights increased with PSD for 100 mm (r=0.51) and 200 mm (r=0.72) fish. Relative condition factors also increased with PSD for 100 mm fish, however the relationship was weak (r=0.30) but a strong correlation was found between Kn and PSD (r=0.81) for 200 mm fish. Based on these results, it appears that either Kn or Wr may be used inassessing the condition of yellow perch from the Indiana waters of Lake Michigan.Department of Biology
5
Lau, Jamie K. "Impacts of channelization on stream habitats and associated fish assemblages in east central Indiana." Virtual Press, 2005. http://liblink.bsu.edu/uhtbin/catkey/1319547.
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The objective of this study was to determine the relationship between fish assemblage structure and habitat in streams dominated by an agricultural landscape. Fishes from 20 natural and 20 channelized streams were sampled using electrofishing gear in East Central Indiana. Streams that had been channelized had a lower quality fish assemblage when compared to natural streams as measured by the Indiana V. Eastern Corn Belt Plain Index of Biotic Integrity (IBI). Stream habitat was evaluated using the Qualitative Habitat Evaluation Index (QHEI), which indicated that channelized streams had lower quality primarily due to a loss of heterogeneous habitat. Pearson correlation analysis relating ECB IBI and QHEI was positive and significant, and demonstrated that a reduction in riffle and pool areas associated with channelization was the most significant factor influencing the fish community. Furthermore, species lost when streams are channelized were predictable, and often represented environmentally sensitive species. The results of this study suggested that stream channel alterations have a negative and lasting influence on the fish assemblage which should be recognized prior to any stream development.Department of Biology
6
Stettner, Craig R. "An analysis of the population dynamics of the yellow perch in Indiana waters of Lake Michigan." Virtual Press, 1989. http://liblink.bsu.edu/uhtbin/catkey/560277.
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Age, growth, and abundance data were collected on yellow perch, Perca fla vescen, in Indiana waters of Lake Michigan in 1987 and 1988. The data collected were compared to data on yellow perch in Indiana waters of Lake Michigan dating back to 1975.Changes in growth, mortality, and abundance between 1975 and 1988 were clearly illustrated by the data. Growth has decreased; back-calculation indicates that "quality" (> 200 mm) perch in 1975 were about age II, however, "quality" perch in 1988 were over age V. Annual mortality values produced from following a cohort or comparing age classes indicate that mortality has decreased since 1981, most sharply in 1987 and 1988. Changes in growth and mortality are likely resultant of large changes in abundance. Indices of abundance (biomass and catch-per-uniteffort) reveal that the yellow perch population has become much more dense in the late 1980's than the 1970's and early 1980's. The percentage of quality perch has decreased, however, the abundance of quality perch has increased and peaked in 1988.Department of Biology
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Brown, Forrest C. "The fish population of an east-central Indiana borrow pit lake with management implications." Virtual Press, 1985. http://liblink.bsu.edu/uhtbin/catkey/412514.
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The fish, invertebrate, and macrophyte communities of Dumpert's Lake, a borrow pit located in northwest Delaware County, Indiana were studied in 1979 and 1980. Data obtained from this study were used to evaluate the potential for quality fishing, to identify sport fish production problems, to assess largemouth bass food habits and habitat utilization, and to consider management options.Bluegill dominated the July and September, 1980 fish collections at 69 and 84 percent, respectively. The growth rates for age II and older bluegill indicated mortality rates above 55 percent. Stocklength (3 in., 76 mm) was.attained at annulus 2 and quality-length (6 in., 152 mm) was reached at age III+. The overall average annual growth increment was 48 mm (1.9 in.). Bluegill were in good condition by overall average K at capture (2.05) and at annulus formation (1.91). Corresponding mean Relative Weight (Wr) values were 106 and 107, respectively.Largemouth bass comprised 23 and 14 percent, respectively, of the July and September, 1980 fish collections. Bass attained stock-length (8 in., 200 mm) by age II+ and an additional 1.5-2.0 years (age III+ or older) was required to attain quality-length (12 in., 300 mm). Growth rates and length-frequency distribution verified mortality rates in excess of 60 percent for all age groups of stock-size bass. Average yearly growth was 70 mm (2.8 in.). Condition was poor by overall average K at capture (1.27) and at annulus formation (1.22). The overall mean Wr was 89 for the respective K values.A stock structure index, Proportional Stock Density (PSD), indicated an unbalanced largemouth bass and bluegill population. Bluegill PSD was 78 with largemouth bass PSD at 27.Radio telemetry observations for two largemouth bass monitored from late May to mid-July, 1980 indicated relative inactivity by observed displacement (98 and 366 m) with respective home ranges of 0.01 and 0.12 ha. Extensive use of shoreline cattails was noted at 79 and 84 percent of the respective locations. All observations were over lake depths of 0.5-0.9 m. Two bass tracked from late July to mid-September, 1980 were more active by displacement (1401 and 1429 m) with home ranges of 0.92 ha for both fish, and similar utilization of submergent pondweeds (46 and 50 percent, respectively). One bass was always observed over lake depths of 1.0 m or greater. The other bass was observed in shallow water (0.5-0.9 m) for 50 percent of the observations.Fish occurred more frequently (71 percent) in stomachs of largemouth bass ranging from 195-247 mm than in stomachs (11 percent) of bass 253-347 mm total length. Insects dominated the diet of the larger fish by percent in volume and weight (66 percent) compared to the smaller stock-size bass (21-22 percent). Odonata was the most frequent insect taxa in the diet of the smaller bass at 29 percent and Ephemeroptera was the dominant insect taxa (33 percent) in the diet of the larger fish.Epifaunal macroinvertebrates were more diverse by taxa compared to macroinvertebrates from three benthic habitats which were about equal in diversity by taxa. Zooplankton diversity by taxa was also similar among the benthic habitats. Macroinvertebrate density showed a trend of seasonal increase for the 1979 summer period, while distinct biomodal peaks for zooplankton abundance occurred in early July and late August, 1979 for vegetated and nonvegetated littoral zones.Najas flexilis, Potamogeton nodosus, and P. pusillus dominated the submergent macrophyte community in 1979. The overall mean seasonal dry weight biomass of macrophytes was 110 g/m2 (114 g/m3 ). Macrophyte control was recommended for improving the sport fishery.Ball State UniversityMuncie, IN 47306
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Gallinat, Michael P. "Population analysis and food habits of the yellow perch, Perca flavescenes (Mitchill), in Indiana waters of Lake Michigan, 1984-86." Virtual Press, 1987. http://liblink.bsu.edu/uhtbin/catkey/483967.
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Yellow perch, Perca flavescens (Mitchill), were collected by trawling and gillnetting in Indiana waters of Lake Michigan near Michigan City, Indiana. Sampling was conducted during the months of June, July and August from 1984 through 1986.Growth rates and length-weight relationships were found to be considerably lower than those reported previously. Males declined 38 mm at age I, 55 mm at age II, 56 mm at age III and 35 mm at age IV comparing 1986 to 1976. Females showed similar declines for the same period at 40 mm for age I, 58 mm at age II, 66 mm at age III and 53 mm at age IV. The primary reason for the decrease in growth appears to be due to the current high population density of yellow perch in Indiana waters of Lake Michigan.Maturation of males for 1986 appears to be slower than that of 1984. All male perch were mature by age III in 1984. However, only 68x of the males were mature at the same age in 1986. In 1984, 94% of the females were mature by age IV while 86% were mature at the same age in 1986.Differences in maturation rate may be a reflection of the reduced growth rates. Size at maturity was found to be similar for both sexes in 1984 and 1986. All females were mature by 230-239 mm in 1984 and 220-229 mm in 1986. All male perch were mature at 180-189 mm in 1984 and 220-229 mm in 1986.Total estimated average annual percent mortalities of 79, 58, 66 and 55 were calculated for combined sexes from age composition analyses end trawl catch data for 1976 and 1984-86. Yellow perch production for 100 fish was estimated for June through August using the Allen curve method. Biomass of substock ( <130 mm), stock ( >129 mm) and quality fish (200 mm or larger) were estimated using Proportional Stock Density to investigate population structure. The Allen curve biomass models were modified to more accurately reflect the trawl catch density data as an index of population changes in 1976 compared to 1984-86. Theoretical biomass for the substock component increased 23 fold from 1976 to 1986. Biomass of the stock sized fish was estimated as 15 times greater in 1986 compared to 1976. Quality fish biomass varied from year to year with the average for 1984-86 estimated as 14 times greater than 1976. The most apparent factor now influencing deterioration of growth and resultant quality of the population is decreased mortality/increased survival with increase in biomass. If the low mortality rates observed for 1984-86 remain unchanged, the data indicate continued population density increases will result in even lower growth rates, and a population dominated by a higher percentage of small, non-quality fish.Food habit analyses for 1984 were compared to a diet study of yellow perch in 1972 for the study area. Zooplankton increased from 0.4x in 1972 to 9% of the volume in 1984 for 100-175 mm perch. This trend may reflect an increase in zooplankton populations in response to the population decline of the planktivorous alewife. Young-of-the-year yellow perch made up 85% of the stomach volume for 176-225 mm perch in 1984 while none were found in samples for 1972. This clearly shows yellow perch are resorting to cannibalism resulting from excessive intraspecific competition.Diet analyses by month revealed alewife eggs were moat important during peak abundance in June and July. Yellow perch (YOY) and Pontocoreia affinis became important during August. Analysis by size interval showed zooplankton and insects (primarily Chironomidae) were important to the diet of perch in the 30-59 mm (YOY) size interval. Copepoda were important by percent volume until approximately 60 mm when the zooplankton component switched to Cladocera. Data for 60-119 mm (age I+) fish indicates alewife eggs were important during June but insects became increasingly more important during July and August. Diversity in food items consumed diminished with increase in size as diet of 120-159 mm (age II+) yellow perch consisted largely of fish. Increases in percent volume of rainbow smelt in June and July, and Y0Y perch in August for age II+ and older perch compared to younger/smaller fish may be related to increased capture success. Diet of fish larger than 160 mm (age III+ and older) consisted almost entirely of rainbow smelt and Y0Y yellow perch.Ball State UniversityMuncie, IN 47306
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Nemeth, Douglas J. "Relationship of Aeromonas hydrophila to fish community health and water quality parameters." Virtual Press, 1985. http://liblink.bsu.edu/uhtbin/catkey/421946.
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Temperature, conductivity, and Aeromonas hydrophila density were determined bimonthly at six sites in the White River drainage system, Delaware County, Indiana, from April, 1984 through December, 1984. Fish were collected from four of the six sites. Fish were identified to species, examined for gross pathology, and their blood collected. Titers against A. hydrophila antigen 157 were determined for all carp (Cyprinus carpio) captured. Certain carp serum samples were also tested against three additional A. hydrophila antigens.Aerononas hydrophila densities appeared to be related to temperature and conductivity, primary producers, and runoff/effluent. Aeromonas hydrophila densities were higher in areas affected by urban runoff/ effluent than in areas affected by rural runoff/effluent. Aeromonas hydrophila densities increased as one progressed through the city of Muncie.Only five percent of all fish captured exhibited signs of gross pathology. Diseased fish typically demonstrated low titers against antigen 157. Several A. hydrophila serotypes were apparently infectious for the carp studied. Thirty-two percent of the carp sampled exhibited a positive titer response against antigen 157. Considerable variation in titer response existed between individuals.Ball State UniversityMuncie, IN 47306
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Duncan, Murray. "The genetic stock structure and distribution of Chrysoblephus Puniceus, a commercially important transboundary linefish species, endemic to the South West Indian Ocean." Thesis, Rhodes University, 2014. http://hdl.handle.net/10962/d1011868.
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Chrysoblephus puniceus is an over-exploited linefish species, endemic to the coastlines off southern Mozambique and eastern South Africa. Over-exploitation and habitat loss are two of the biggest threats to the sustainability of fisheries globally. Assessing the genetic stock structure (a prerequisite for effective management) and predicting climate related range changes will provide a better understanding of these threats to C. puniceus which can be used to improve the sustainability of the fishery. Two hundred and eighty four genetic samples were collected from eight sampling sites between Ponta da Barra in Mozambique and Coffee Bay in South Africa. The mitochondrial control region and ten microsatellite loci were amplified to analyse the stock structure of C. puniceus. The majority of microsatellite and mtDNA pairwise population comparisons were not significant (P > 0.05) although Xai Xai and Inhaca populations had some significant population comparisons for mtDNA (P < 0.05). AMOVA did not explain any significant variation at the between groups hierarchical level for any pre-defined groupings except for a mtDNA grouping which separated out Xai Xai and Inhaca from other sampling sites. SAMOVA, isolation by distance tests, structure analysis, principle component analysis and spatial autocorrelation analysis all indicated a single population of C. puniceus as being most likely. The migrate-n analysis provided evidence of current driven larval transport, with net migration rates influenced by current dynamics.Two hundred and thirty six unique presence points of C. puniceus were correlated with seasonal maximum and minimum temperature data and bathymetry to model the current distribution and predict future distribution changes of the species up until 2030. Eight individual species distribution models were developed and combined into a mean ensemble model using the Biomod2 package. Winter minimum temperature was the most important variable in determining models outputs. Overall the ensemble model was accurate with a true skills statistic score of 0.962. Binary transformed mean ensemble models predicted a northern and southern range contraction of C. puniceus' distribution of 15 percent; by 2030. The mean ensemble probability of occurrence models indicated that C. puniceus' abundance is likely to decrease off the southern Mozambique coastline but remain high off KwaZulu-Natal. The results of the genetic analysis support the theory of external recruitment sustaining the KwaZulu Natal fishery for C. puniceus. While the high genetic diversity and connectivity may make C. puniceus more resilient to disturbances, the loss of 15 percent; distribution and 11 percent; genetic diversity by 2030 will increase the species vulnerability. The decrease in abundance of C. puniceus off southern Mozambique together with current widespread exploitation levels could result in the collapse of the fishery. A single transboundary stock of C. puniceus highlights the need for co-management of the species. A combined stock assessment between South Africa and Mozambique and the development of further Marine Protected Areas off southern Mozambique are suggested as management options to minimise the vulnerability of this species.
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Wartenberg, Reece. "On the underwater visual census of Western Indian Ocean coral reef fishes." Thesis, Rhodes University, 2012. http://hdl.handle.net/10962/d1005153.
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This study conducted the first high-resolution investigation of the ichthyofaunal assemblages on a high-latitude coral reef in the Western Indian Ocean (WIO). Two-Mile reef, in South Africa, is a large, accessible patch-reef, and was selected as a candidate study area. Although the effect of season in structuring coral reef fish communities is most-often overlooked, the relationship between these fish communities and their habitat structure has been investigated. In South Africa, however, neither of these potential community-level drivers has been explored. As coral reefs worldwide are faced with high levels of usage pressure, nondestructive underwater visual census (UVC) techniques were identified as the most appropriate survey methods. This study had two primary aims that were; (1) to identify the most suitable technique for the UVC of coral reef fishes, and to test variations of the selected technique for appropriateness to implementation in long-term monitoring programs, and (2) to determine if possible changes to ichthyofaunal community structure could be related to trends in season and/or habitat characteristics. A review of the literature indicated that the most appropriate UVC method for surveying epibenthic coral reef fishes is underwater transecting. To compare the traditional slate-based transects to variations that implement digital image technology, slate transects were compared to a first-attempt digital photographic transect technique, and digital videographic transects. Videographic transects produced the most favourable species richness, abundance, and standard deviations of the three techniques. Diversity was not significantly different between transect techniques. The minimum required sample size was lowest for videographic transects (17 replicates), intermediate for photographic transects (27 replicates) and highest for slate transects (37 replicates). Videographic and photographic transects required greater analysis time to generate counts, but required lower observer training time. While videographic transects produced the lowest proportion of species considered unidentifiable, all three transect techniques showed similar functionality to surveying epibenthic coral reef fishes. Videographic transects were therefore identified as the most appropriate UVC technique for this study. Videographic transects at shallow (6 – 14 m), intermediate (14 – 22 m) and deep (22 – 30 m) depths in mid-winter and mid-summer, sampled a total of 41 families consisting of 209 species and 18172 individuals, dominated by pomacentrids in abundance and labrids in richness. The fish assemblages on Two-Mile Reef were found to be similar in composition to lower-latitude WIO reefs. Overall ichthyofaunal abundance and richness was significantly higher in summer than in winter, and was higher at shallow sites than at intermediate and deep sites. A multivariate approach confirmed differences between seasons at shallow depths but not between seasons at intermediate and deep depths. The fish assemblages on Two-Mile Reef can therefore be described as being comprised of four relatively distinct communities: a shallow, winter community; a shallow, summer community; a year-round intermediate community; and a year-round deep community. The distributions of discriminating species indicated that high abundances of the algal-feeding pomacentrids are observed only at shallow and intermediate sites while high abundances of the zooplanktivorous serranid subfamily, the Anthiinae, are observed predominantly at deep sites. Assessment of all measured supplementary variables indicated that of all factor combinations, observed patterns could be ascribed most strongly to depth. Quantification of reef characteristics indicated that as depth increases, habitat complexity decreases, benthic communities shift from dense coral domination to sparse sponge domination, and algal biomass and cover decreases. The ability of the videographic transect technique to detect changes in community structure with season and depth indicates that season and depth should be accounted for in future high-latitude ichtyofaunal surveys, and that the videographic transect technique is suitable for implementation in long-term monitoring programs on coral reefs. The similarity in fish assemblages between Two-Mile Reef and lower latitude regions suggests that the protocol for surveying epibenthic coral reef fishes, resulting from this study, is relevant throughout the continental WIO.
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Fischer, Stefanie Jane. "Human capital accumulation among Native Americans an empirical analysis of the national assessment of educational progress /." Thesis, Montana State University, 2009. http://etd.lib.montana.edu/etd/2009/fischer/FischerS0509.pdf.
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Native Americans have low levels of human capital accumulation. In 2005, only 21% scored at the proficient level on the NAEP math test compared with 37% of all other test takers. One cause of their low human capital accumulation may be factors that commonly explain low academic performance among other minority groups within the United States, such as school quality and family background. Alternatively, Native American students may perform low academically due to factors that are unique to this population such as living on Native land or the political institutions that govern them. This paper will empirically examine Native American students' human capital accumulation decisions. Using data from the National Assessment of Educational Progress (NAEP), I find Native American students residing on Native land score 1/4 of a standard deviation lower on the math assessment than Native American students living off Native land, with no other controls added. After controlling for other area characteristics, family background, peer effects and school resources, the effect of living on Native land is not statistically significant in explaining test scores. Family background and peer effects explain most of the variation in Native American students' human capital accumulation decision. Students who identify with the white peer group score 1/5 of a standard deviation higher than students who identify with the Native American peer group. Although legal institutions do not explain student test scores, they do appear to affect students' attendance. Students living in areas under tribal jurisdiction are 13% more likely to miss a week or more of school in a month, ceteris paribus.
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Bunce, Tracie E. "Quality of life indicator for suburban development case study : Fishers, Indiana." Virtual Press, 2001. http://liblink.bsu.edu/uhtbin/catkey/1217393.
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This study presents an indicator system created for the Town of Fishers, Indiana to examine and evaluate the quality of life within the community. After reviewing other communities' indicator projects, a series of 20 indicators were developed for the Town of Fishers. There is a brief discussion and a possible source of data for each indicator. The indicators can be utilized by the community leaders and residents to monitor the quality of life. To continue this study, Fishers can create a benchmarking system to set goals for the future of the community.Department of Urban Planning
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Hamilton, Brett Russell. "Analysis and characterisation of ciguatoxins present in fish of the Indian Ocean, the Pacific Ocean, and the Caribbean Sea /." [St. Lucia, Qld.], 2002. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe17143.pdf.
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Singleton, Sara. "Common problems, collective action and efficiency : the evolution of institutions of co-management in Pacific Northwest tribal fisheries /." Thesis, Connect to this title online; UW restricted, 1994. http://hdl.handle.net/1773/10739.
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Cwalinski, Tim A. "Simulated forecasting of yellow perch (Perca flavescens) relative population density for Indiana waters of Lake Michigan : responses to varying harvest and alewife density." Virtual Press, 1996. http://liblink.bsu.edu/uhtbin/catkey/1036196.
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The yellow perch, (Perca flavescens), is an important commercial and sport fish in Indiana waters of Lake Michigan. The population is currently managed by temporary restrictions of commercial harvest. A computer simulation model was developed to examine the effects of various constant harvest quotas and alewife densities on yellow perch relative numbers.Model design is based on the SLAM II simulation language incorporating a FORTRAN biological subroutine. The age-structured population model includes measured or predicted biological characteristics of the dynamic pool model. Recruitment is based on a preestablished three-dimensional Ricker stock-recruitment function including alewife (Alosa pseudoharengus) species interaction as a constant or stochastic factor. Sex-specific natural mortality rates were established through life history parameter analysis and the von Bertalanffy growth factors. Density-dependent growth is incorporated into each year of a model run and fluctuates with the simultaneous density of fish. Constant levels of commercial harvest ranging from 0 to 700,000 kg were used in 20-year forecasts. Initial conditions for model runs were 1984 and 1994 trawl CPUE levels when yellow perch were at high and low levels, respectively according to standardized sampling. Response variables were examined as mean catches over each forecast length and included: age 2 fish, spawning stock (z 190 mm), and total catch > age 1.Alewife densities had a tremendous impact on mean catches of the response variables. Highest catches under any forecast period occurred when alewife was considered absent from the system. Catches declined as alewife density was increased as a 20-year constant under each harvest regimen.Catches of spawning size fish were maintained at highest levels for all forecast periods when harvest was set to zero. Catches of young fish were moderate with this harvest regimen if initial catch conditions were high such as in 1984. Catches of young fish were always higher in the absence of a commercial fishery if initial catch conditions were low such as in 1994. Low to moderate harvest quotas could maintain moderate levels of young fish for the forecast length if initial model conditions were high. However, these quota levels for the 1984-2004 forecast length resulted in lower mean catches of spawning size fish as compared to the no commercial fishery regimen. The best case scenario for all response variables when initial catch conditions were low was under a no commercial harvest regimen.Department of Biology
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Springbok–Njokweni, Nosiphiwo. "Regional differentiation of three goatfishes (Parupeneus Spp.) within the Western Indian Ocean." Thesis, University of Fort Hare, 2015. http://hdl.handle.net/10353/d1020262.
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Goatfishes inhabit inshore reefs and corals and are commercially important across their distribution in the Western Indian Ocean (WIO). The biogeography of these species in the WIO has not been explored with regards to their levels of diversity and relationships among regions. The genetic connectivity and differentiation of three goatfishes of the genus Parupeneus (P. barberinus, P. macronemus and P. rubescens) was studied using two mitochondrial genes (ND2 and 16S rRNA) and one nuclear gene (RAG1) using specimens from East and southern Africa, islands around the Mascarene plateau, Oman, Maldives and the Red Sea. Haplotype diversities, networks and AMOVA were used to measure genetic variance among localities and defined regional groups. There were high haplotype (HD > 0.9) and low nucleotide diversities (< 0.006) among all species for all gene regions, suggesting high levels of genetic differentiation among different areas, except for the mtDNA 16S data for P. macronemus and P. rubescens. For all three species, the FST population pairwise values revealed significant differentiation in all datasets for most population pairwise comparisons with the Maldives and genetic connectivity with haplotypes being shared among other localities. The 16S and RAG1, AMOVA for P. barberinus revealed a significant (P < 0.05) strong genetic structure among groups, for example P = 0.00 was estimated in the 16S data for four groups (the Maldives, WIO islands, Kenya and eastern mainland). This study found evidence for regional differentiation within the WIO for these three species supporting the presence of genetic breaks among areas. This differentiation could be either due to the historical isolation among areas or due to geographic and oceanic barriers such as the Mascarene Plateau and the Agulhas Current eddies in the Mozambique Channel. The effects of oceanographic features and physical barriers in the species distribution range and the dispersal potential based on the life history features of the species can have an influence on the genetic structuring of a population. It is also important to note that the length of the pelagic larval phase is just one factor affecting dispersal in marine organisms that can also explain the difference in genetic population structure. Unfortunately there is no specific information on the larval dispersal of these three goatfish. Therefore, studies are needed to be conducted on the specific biology and life history strategies of each Parupeneus species. These results suggest the importance of other factors, such as currents, and larval retention that may cause strong differentiation. These factors should also be considered when observing larval dispersal and its effect on population genetic structure. This study support the hypotheses that physical factors, processes (geographic barriers and oceanographic characteristics) and life history parameters need to be studied to understand the genetic differentiation of these Parupeneus reef fishes.
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Sapp, Shawn A. "Population trends of major near-shore fish species in Indiana waters of Lake Michigan." Virtual Press, 1999. http://liblink.bsu.edu/uhtbin/catkey/1125023.
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The purpose of this research was to determine population trends of major nearshore fish species in Indiana waters of Lake Michigan from 1984 to 1998 to gain insight into species dynamics. Index trawl samples were collected twice monthly from June through August at three locations. Trends of catch-per-unit-effort (CPUE) were investigated for the most abundant species: yellow perch (Perca flavescens), alewife (Alosa pseudoharengus), spottail shiner (Notropis hudsonius), rainbow smelt (Osmerus mord iz), and bloater (Coregonus hoyi). Trawl catch of yellow perch, alewife, and spottail shiners at sites M, K, and G were strongly correlated suggesting similar fluctuations. Young-of-the-year trawl catch revealed that insight to population dynamics of species was not always reliable. Trawl CPUE of > age 1 fish provided insight to dynamics of the major species at all sample locations with strong trend similarities between sites. No strong major species interactions were found using simple linear correlations.Department of Biology
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Boxberger, Daniel L. "Resource allocation and control on the Lummi Indian reservation : a century of conflict and change in the salmon fishery." Thesis, University of British Columbia, 1986. http://hdl.handle.net/2429/26962.
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This study focuses on the Lummi Indian fishers of Northwest Washington State, and the manner in which they have been included in and excluded from the commercial fishing industry over the past one hundred years. The approach to be taken in this situation of internal dependency is to examine access to resources. The control of productive resources — land, water, timber, minerals, and fish. — that Indians own or have access to, presents an ideal starting point for understanding Indian underdevelopment.
Prior to and immediately after the time the Lummi were confined to a reservation, they were engaged in a traditional fishery that met their needs for subsistence and had the potential to develop into a viable commercial endeavor. The penetration of capital into the commercial salmon fishery of North Puget Sound initially utilized Lummi labor, but the development of new extractive technologies and an increase in the availability of labor of other ethnicities rapidly circumvented the need for Indian labor. Concomitantly, throughout the early 1900s, efforts by the State of Washington to curtail Indian fishing resulted in the Lummi being confined to a small reservation fishery of insignificant commercial potential. In the 1940s, when Lummi exclusion from the fishery was almost total, the need for fishers suddenly became acute, and the Lummi were once again incorporated into the commercial salmon fishery. Nevertheless, the post-war era again saw new developments in the salmon industry, and, no longer needed by the processors, the Lummi were once again squeezed out of the industry.
Sympathetic court cases in the late 1960s and early 1970s guaranteed commercially significant fishing opportunity for the Lummi. Nevertheless, the present Lummi salmon fishery is not going to provide the Lummi with a viable economic base. The manner in which the fishery has developed is causing the majority of the economic yield of the fishery to be siphoned off to non-Lummi interests.
Utilizing ethnohistorical and ethnographic data, this study examines a dependency approach to understanding Lummi underdevelopment. By focusing primarily on economic and political dependency on the United States Federal Government, this study shows how the Lummi community was incorporated into the dominant society and became a dependent community suffering from chronic underdevelopment, despite access to and utilization of a valuable natural resource.Arts, Faculty of
Anthropology, Department of
Graduate
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Thoms, J. Michael. "Ojibwa fishing grounds a history of Ontario fisheries law, science, and the sportsmen's challenge to aboriginal treaty rights, 1650-1900 /." online access from Digital Dissertation Consortium access full-text, 2004. http://libweb.cityu.edu.hk/cgi-bin/er/db/ddcdiss.pl?NQ90280.
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Beugly, Jayson S. "Fish and invertebrate communities in agricultural headwater streams." Virtual Press, 2008. http://liblink.bsu.edu/uhtbin/catkey/1391472.
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Agricultural practices may influence stream biological communities by removing riparian vegetation and modifying stream channel morphology, both which may reduce water retention time. I collected benthic invertebrates and fishes in seven headwater agriculturally-influenced streams in central Indiana, to quantify controls on invertebrate and fish community assemblage variation. Invertebrates were collected at 14 sites and fish were collected at 12 sites in Buck Creek watershed. The abundances of invertebrates and fishes were analyzed in Detrended Correspondence Analyses (DCA) in PC-ORD software and correlated with abiotic and biotic factors. The sites located in close proximity to Buck Creek have increased stability of biotic (fish assemblages) and abiotic (flow and water depth) factors. Abundances of invertebrates of headwater streams in east-central Indiana agricultural landscapes are influenced by distance between sites, distance to Buck Creek, and presence of fish species. Abundances of fishes were correlated with water quality and distance to Buck Creek.Department of Biology
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Smith, Virginia M. "The relocation of the Eli Lilly Farm Office and an adaptive use and/or rehabilitation proposal." Virtual Press, 2008. http://liblink.bsu.edu/uhtbin/catkey/1397796.
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David Kroll, Director of the Preservation Studio at RATIO Architects, Inc. in Indianapolis, approached me in September of 2007 about a project. The Eli Lilly Farm in Carmel, Indiana was in danger of demolition. The property was sold to a development company who was proposing an idea for over 1000 homes as a part of a "Master Planned Community" to be built on 335 acres of land. One of the stipulations of this sale was that the Conner Prairie Living History Museum had first right of refusal on any of the buildings from the property. The idea had been brought up to relocate a couple of the buildings on the farm to save them from demolition. I decided to document the farm so that future generations could know what used to exist there. That idea developed into my current topic: "A Study of the Relocation of the Eli Lilly Farm Office with adaptive use Options and Rehabilitation Recommendations."Department of Architecture
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Reidy, Christopher R. "The composition, structure, and distribution of the plant communities of Wilbur Wright Fish and Wildlife Area." Virtual Press, 2002. http://liblink.bsu.edu/uhtbin/catkey/1237766.
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The purpose of this study was to describe the composition, structure and spatial distribution of plant communities at Wilbur Wright Fish and Wildlife Area (WWFWA) in order to provide baseline information to which future conditions can be compared. The plant communities of WWFWA were delineated, sampled, and subsequently classified using the framework of the National Vegetation Classification System. Data were collected for three strata of vegetation: overstory, understory and groundcover. Five permanent plots were established in the forested communities to monitor changes in vegetation over time.Eleven general habitat types were described for WWFWA. Plant communities varied from highly diverse mature woods to successional communities dominated by exotic vegetation. The composition and structure of plant communities appears to be closely related to previous land-use. Management practices are recommended in order to improve the condition of depauperate plant communities and to maintain the integrity of native plant communities.Department of Biology
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Weitzel, David L. "Status and ecology of walleye (Sander vitreus) and sauger (Sander canadense) in the Wabash River, Indiana." Virtual Press, 2004. http://liblink.bsu.edu/uhtbin/catkey/1286768.
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This study has presented a comprehensive overview of the status and ecology of walleye and sauger in the Wabash River, Indiana. Populations of walleye and sauger are relatively low in numbers. Both species exhibited a trend of increased abundance with river km from the mouth of the Wabash River. Summer walleye habitat use and movements were examined in the upper Wabash River. Walleye preferred run habitat over riffle or pool habitat. Lateral position, substrate use, and mean depth appeared to be influenced by discharge. Movements were generally short and occurred within a relatively small home range of 1.7 km. The population size limits the fisheries potential for walleye and sauger in the Wabash River mainstem. The upper Wabash River supports higher abundances of these species than the middle Wabash River and may provide a focal point for future management efforts.Department of Biology
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Bourillon-Moreno, Luis. "Exclusive fishing zone as a strategy for managing fishery resources by the Seri Indians, Gulf of California, Mexico." Diss., The University of Arizona, 2002. http://hdl.handle.net/10150/279963.
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I analyzed the Seri Exclusive Fishing Zone (SEFZ) in the Gulf of California, to assess its efficiency in solving common fisheries management problems related to open access resources. A review of the major historical changes in the socio-cultural context of marine natural resource use in the region showed the SEFZ has allowed the Seri to successfully keep and improve control of access to the Infiernillo Channel, as well as reduce competition with fishers from Bahia Kino in a region with increasing competition for marine resources. However, the SEFZ showed severe limitations that produced conflicts of variable intensity. The most important were lack of clear geographic limits to SEFZ, clear systems to transfer fishing rights, and rights to defend with armed guards the integrity of their marine territory. The role of Seri and Federal Government authorities in conflict creation and resolution and the perception of the outcomes of these conflicts for Seri and Bahia Kino fishers are analyzed on four recent conflict events. Several potential opportunities to promote co-management of fisheries by the federal government and local fisheries management authorities emerged from the SEFZ. However, none of these opportunities, in the form of informal arrangements, succeeded in creating better relationships between Seri and Bahia Kino communities of fishers. I used the jaiba (Callinectes bellicosus) crab fishery inside the SEFZ to assess dynamics of marine resources under Seri common property ownership. I found that inside the SEFZ fishing effort is controlled, the fishing ban is honored, fishing areas are rotated throughout the season, and no-fishing zones are functional. I used data from jaiba buyers, and extensive catch sampling during two fishing seasons, to determine yearly production in Punta Chueca, as well as average daily catch and other descriptive catch statistics. Jaiba is an important resource in the economy of Punta Chueca, and its local management has been facilitated by the SEFZ to produce a fishery that, to date, appears to be sustainable. However, the long-term viability of this fishery inside the SEFZ is vulnerable to outside harvesting patterns and to political and economic influences over which the Seri have no control.
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Foy, Joseph P. "Selected population characteristics of smallmouth bass and rock bass in a three county area of the West Fork of the White River, Indiana from 1991-1994." Virtual Press, 2000. http://liblink.bsu.edu/uhtbin/catkey/1177972.
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Several population characteristics were calculated for smallmouth bass Micropterus dolomieui and rock bass Ambloplites rupestris populations on the west fork of the White River in Randolph, Delaware, and Madison counties, Indiana and were compared to other populations. When compared to streams of similar size in Indiana that were sampled with the same methods, relative abundance (CPUE) of smallmouth bass was average (18.9-35.0 fish/hour) while rock bass were two to ten times more abundant (44.3-53.0 fish/hour). Age analysis and back calculation of length at age were only performed for smallmouth bass. These results indicated strong year classes were cyclical and smallmouth bass growth was above average for Indiana streams, but average for streams of the Midwest. Proportional stock density values were average for smallmouth bass (28-39%) and slightly below average for rock bass (17-33%). Strong weight-length models were also found for both species and relative weight values were optimal.Department of Biology
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Allen, Paul J. "A computer simulation model for the yellow perch population in the Indiana waters of Lake Michigan." Virtual Press, 2000. http://liblink.bsu.edu/uhtbin/catkey/1177967.
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A computer simulation model was developed to examine the effects of various levels of alewife densities, harvest, and bycatch rates on yellow perch Perca flavescens relative densities in Indiana waters of Lake Michigan. The model utilized STELLA® Research software to develop the age-structured population model to include measured or predicted biological characteristics of density-dependent growth, recruitment, and mortality.The model was validated by simulating historically documented yellow perch catch per unit effort (CPUE) from 1984 - 1998. A strong linear relationship (R2= 0.70) between the model predicted CPUE values and the actual CPUE values was found. Twenty year model projections were performed using 1998 yellow perch trawl CPUE as starting values. Alewife abundance was established as either constantly high, constantly low, or allowed to fluctuate randomly and forecasts made used the average of 100 runs. Harvest was imposed on the yellow perch population at 20, 40, and 60% rate levels for fish >_ 200 mm coupled with bycatch at20, 40 and 60% rate levels for fish ranging from 165 - 200 mm.Alewife abundance was the major factor determining the relative abundance of the yellow perch population. On average, constantly high alewife abundance with no harvest or bycatch resulted in projected continuing suppression of yellow perch abundance from 1998 levels. The model predicted the population to rebound using constant low and random alewife abundance with no harvest or bycatch to approximately 1,100 fish/h and 700 fish/h, respectively.The model revealed harvest to have a generally negative impact on the yellow perch population. Increasing harvest and bycatch rate levels resulted in the suppression of projected increases in yellow perch relative abundance. Additionally, increasing harvest and bycatch rates resulted in greater predicted declines in yellow perch abundance.Department of Biology
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Clement, Jessica. "Environmentally concious [sic] site design : a LAND code strategy." Virtual Press, 2008. http://liblink.bsu.edu/uhtbin/catkey/1397793.
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The purpose of this creative project was to develop a master plan for a 450-acre site based on the recently published Land and Natural Development (LAND) Code: Guidelines for Sustainable Land Development by Diana Balmori and Gaboury Benoit. Balmori and Benoit present environmentally conscious design principles that serve as a demonstration for tangible ways to create sustainable landscapes that balance function with the need to preserve natural resources. The outcome of this project includes a detailed master plan for a 450-acre portion of Goose Pond Fish and Wildlife Area (GPFWA) located in Linton, Indiana, which serves as a model for sustainable site design in addition to offering interpretive and recreational opportunities within the focus area.Department of Landscape Architecture
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Cruz, Claudinei da [UNESP]. "Aspectos toxicológicos de paration metílico e de extrato aquoso de folhas secas de nim (Azadirachta indica) para o pacu (Piaractus mesopotamicus) e eficácia no controle de monogenea Dactylogyridae." Universidade Estadual Paulista (UNESP), 2005. http://hdl.handle.net/11449/144159.
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Universidade Estadual Paulista (UNESP)
Os objetivos desse trabalho foram determinar a concentração letal 50% (CL (I) 50-96h) do paration metílico e da azadiractina contida no extrato aquoso de folhas secas de nim (EAFSN) para o pacu (Piaractus mesopotamicus); avaliar a eficácia, concentrações seguras e o tempo de exposição do paration metílico e da azadiractina contida no EAFSN para o controle do Anacanthorus penilabiatus; avaliar as alterações nas brânquias e no fígado dos peixes expostos a concentrações subletais de paration metílico e a azadiractina; e determinar a presença resíduo de azadiractina por cromatografia líquida de alta eficiência (CLAE), no pacu (Piaractus mesopotamicus. A CL (I) 50-96h calculada do paration metílico foi de 3,97 mg/L para os alevinos e de 9,89 mg/L para os jovens. Para a azadiractina contida no EAFSN foi de 1,20 mg/L para os alevinos e de 1,18 mg/L para os jovens. O paration metílico foi menos tóxico para os alevinos e jovens de pacu do que a azadiractina. Nas brânquias, o paration metílico causou congestão, fusão lamelar, edemas subepiteliais, hemorragias intersticiais, fusão lamelar e desorganização da estrutura lamelar e a azadiractina, edema subepitelial, fusão apical das lamelas secundárias. No fígado, o paration metílico causou congestão, fusão celular, hiperplasia dos hepatócitos e desarranjo da organização cordonal dos hepatócitos e a azadiractina, desorganização do arranjo cordonal dos hepatócitos, vacuolização citoplasmática, necrose das células epiteliais de revestimento dos canalículos biliares. O paration metílico foi mais eficiente que o EAFSN no controle dos parasitos monogenéticos, cujo controle foi proporcional ao aumento da concentração na água e ao tempo de exposição. A maior eficácia do paration metílico foi com 7 mg/L, que controlou 96,2 % dos parasitos às 16 horas de exposição e 97,0% às 24 e do EAFNS, com 2,9 mg/L de...
The objectives of the present study were 1) to determine the 50% lethal concentration (LC (l)50-96h) of methyl parathion and azadirachtin present in the aqueous extract of dry neem leaves (AEDNL) for pacu (Piaractus mesopotamicus), 2) to evaluate the efficacy, safe concentrations and exposure time of methyl parathion and azadirachtin for the control of Anacanthorus penilabiatus, 3) to assess the alterations that occur in the gills and liver of fish exposed to sublethal concentrations of methyl parathion and azadirachtin, and 4) to determine the presence of azadirachtin residues in pacu (Piaractus mesopotamicus) by high-performance liquid chromatography HPLC. The calculated LC (l) 50-96h of methyl parathion was 3.97 mg/L for fry pacu and 9.89 mg/L for juvenile fish. The LC (l) 50-96h of azadirachtin present in AEDNL was 1.20 and 1.18 mg/L for fry and juvenile fish, respectively. Methyl parathion was less toxic to fry and juvenile pacu than azadirachtin. In gills, methyl parathion caused congestion, lamellar fusion, subepithelial edema, interstitial hemorrhage, and disorganization of the lamellar structure, whereas azadirachtin caused subepithelial edema and apical fusion of secondary lamellae. In the liver, methyl parathion caused congestion, cell fusion, hepatocyte hyperplasia and derangement of the cord-like organization of hepatocytes, and azadirachtin caused disorganization of the cord-like arrangement of hepatocytes, cytoplasmic vacuolization, and necrosis of epithelial cells lining the bile canaliculi. Methyl parathion was more effective than the AEDNL in the control of monogenetic parasites, with this control being proportional to the increase of the insecticide's concentration in water and of exposure time. The highest efficacy of methyl parathion was observed at a concentration of 7 mg/L, with a 96.2% rate of parasite control after 16 h of exposure and a 97.0% rate after 24 h. For AEDNL, a...
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Cruz, Claudinei da. "Aspectos toxicológicos de paration metílico e de extrato aquoso de folhas secas de nim (Azadirachta indica) para o pacu (Piaractus mesopotamicus) e eficácia no controle de monogenea Dactylogyridae /." Jaboticabal, 2005. http://hdl.handle.net/11449/144159.
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Orientador: Joaquim Gonçalves Machado NetoCoorientador: Manoel Lima de Menezes
Banca: Flávio Ruas de Moraes
Banca: Maurício Laterça Martins
Banca: Robinson Antonio Pitelli
Banca: Julio Vicente Lorbardi
Resumo: Os objetivos desse trabalho foram determinar a concentração letal 50% (CL (I) 50-96h) do paration metílico e da azadiractina contida no extrato aquoso de folhas secas de nim (EAFSN) para o pacu (Piaractus mesopotamicus); avaliar a eficácia, concentrações seguras e o tempo de exposição do paration metílico e da azadiractina contida no EAFSN para o controle do Anacanthorus penilabiatus; avaliar as alterações nas brânquias e no fígado dos peixes expostos a concentrações subletais de paration metílico e a azadiractina; e determinar a presença resíduo de azadiractina por cromatografia líquida de alta eficiência (CLAE), no pacu (Piaractus mesopotamicus. A CL (I) 50-96h calculada do paration metílico foi de 3,97 mg/L para os alevinos e de 9,89 mg/L para os jovens. Para a azadiractina contida no EAFSN foi de 1,20 mg/L para os alevinos e de 1,18 mg/L para os jovens. O paration metílico foi menos tóxico para os alevinos e jovens de pacu do que a azadiractina. Nas brânquias, o paration metílico causou congestão, fusão lamelar, edemas subepiteliais, hemorragias intersticiais, fusão lamelar e desorganização da estrutura lamelar e a azadiractina, edema subepitelial, fusão apical das lamelas secundárias. No fígado, o paration metílico causou congestão, fusão celular, hiperplasia dos hepatócitos e desarranjo da organização cordonal dos hepatócitos e a azadiractina, desorganização do arranjo cordonal dos hepatócitos, vacuolização citoplasmática, necrose das células epiteliais de revestimento dos canalículos biliares. O paration metílico foi mais eficiente que o EAFSN no controle dos parasitos monogenéticos, cujo controle foi proporcional ao aumento da concentração na água e ao tempo de exposição. A maior eficácia do paration metílico foi com 7 mg/L, que controlou 96,2 % dos parasitos às 16 horas de exposição e 97,0% às 24 e do EAFNS, com 2,9 mg/L de...
Abstract: The objectives of the present study were 1) to determine the 50% lethal concentration (LC (l)50-96h) of methyl parathion and azadirachtin present in the aqueous extract of dry neem leaves (AEDNL) for pacu (Piaractus mesopotamicus), 2) to evaluate the efficacy, safe concentrations and exposure time of methyl parathion and azadirachtin for the control of Anacanthorus penilabiatus, 3) to assess the alterations that occur in the gills and liver of fish exposed to sublethal concentrations of methyl parathion and azadirachtin, and 4) to determine the presence of azadirachtin residues in pacu (Piaractus mesopotamicus) by high-performance liquid chromatography HPLC. The calculated LC (l) 50-96h of methyl parathion was 3.97 mg/L for fry pacu and 9.89 mg/L for juvenile fish. The LC (l) 50-96h of azadirachtin present in AEDNL was 1.20 and 1.18 mg/L for fry and juvenile fish, respectively. Methyl parathion was less toxic to fry and juvenile pacu than azadirachtin. In gills, methyl parathion caused congestion, lamellar fusion, subepithelial edema, interstitial hemorrhage, and disorganization of the lamellar structure, whereas azadirachtin caused subepithelial edema and apical fusion of secondary lamellae. In the liver, methyl parathion caused congestion, cell fusion, hepatocyte hyperplasia and derangement of the cord-like organization of hepatocytes, and azadirachtin caused disorganization of the cord-like arrangement of hepatocytes, cytoplasmic vacuolization, and necrosis of epithelial cells lining the bile canaliculi. Methyl parathion was more effective than the AEDNL in the control of monogenetic parasites, with this control being proportional to the increase of the insecticide's concentration in water and of exposure time. The highest efficacy of methyl parathion was observed at a concentration of 7 mg/L, with a 96.2% rate of parasite control after 16 h of exposure and a 97.0% rate after 24 h. For AEDNL, a...
Doutor
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Rawson, Timothy Mark. ""In common with all citizens" : sportsmen, Indians, fish, and conservation in Oregon and Washington /." view abstract or download file of text, 2002. http://wwwlib.umi.com/cr/uoregon/fullcit?p3072604.
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Thesis (Ph. D.)--University of Oregon, 2002.Typescript. Includes vita and abstract. Includes bibliographical references (leaves 330-363). Also available for download via the World Wide Web; free to University of Oregon users.
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Fischer, Heike Verfasser], Uwe [Akademischer Betreuer] [Wilkesmann, and Sigrid [Akademischer Betreuer] Metz-Göckl. "Motivational Dynamics of Education in Indian Society : A Socio-Cultural Exploration / Heike Fischer. Betreuer: Uwe Wilkesmann. Gutachter: Sigrid Metz-Göckl." Dortmund : Universitätsbibliothek Dortmund, 2012. http://d-nb.info/1099294738/34.
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Fischer, Heike [Verfasser], Uwe [Akademischer Betreuer] Wilkesmann, and Sigrid [Akademischer Betreuer] Metz-Göckl. "Motivational Dynamics of Education in Indian Society : A Socio-Cultural Exploration / Heike Fischer. Betreuer: Uwe Wilkesmann. Gutachter: Sigrid Metz-Göckl." Dortmund : Universitätsbibliothek Dortmund, 2012. http://d-nb.info/1099294738/34.
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Fischer, Alexander [Verfasser], and Subrata K. [Akademischer Betreuer] Mitra. "The Judicialisation of Politics in India: Origins and Consequences of the Power of the Indian Supreme Court / Alexander Fischer ; Betreuer: Subrata K. Mitra." Heidelberg : Universitätsbibliothek Heidelberg, 2020. http://d-nb.info/1222268019/34.
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Fischer, Alexander [Verfasser], and Subrata Kumar [Akademischer Betreuer] Mitra. "The Judicialisation of Politics in India: Origins and Consequences of the Power of the Indian Supreme Court / Alexander Fischer ; Betreuer: Subrata K. Mitra." Heidelberg : Universitätsbibliothek Heidelberg, 2020. http://nbn-resolving.de/urn:nbn:de:bsz:16-heidok-253645.
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McMinn, Miranda. "Tourism, coastal livelihoods, vulnerability and governance in South India : tourism, actors and artisanal marine fishers in Varkala, Kerala." Thesis, King's College London (University of London), 2006. https://kclpure.kcl.ac.uk/portal/en/theses/tourism-coastal-livelihoods-vulnerability-and-governance-in-south-india--tourism-actors-and-artisanal-marine-fishers-in-varkala-kerala(abd7d183-864b-4d7a-8321-218057749837).html.
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Yahya, Saleh A. S. "Habitat structure, degradation and management effects on coral reef fish communities." Doctoral thesis, Stockholms universitet, Zoologiska institutionen, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-62187.
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Coral reefs are among the most diverse and productive ecosystems on earth, and are critical to the survival of tropical marine ecosystems and sustenance of local human populations. However, coral reefs are quite vulnerable to disturbances, both natural and anthropogenic. This thesis looks at how coral reef communities have responded to climactic disturbances, particularly the 1997-98 El Niño Southern Oscillation (ENSO) and subsequent coral bleaching and mortality that affected much of the Indian Ocean, including the coastal waters of Tanzania, where the study was conducted. In particular, it investigates the effects of coral bleaching, habitat degradation and reef spatial arrangement on reef fish assemblages. Habitat structural complexity and spatial arrangement of reefs had an effect on reef fish communities. Fish communities showed patterns in distribution among habitats and between patch and continuous reefs. Fishes preferred live to bleached/dead or eroded coral, but trophic groups reacted differently to patch and continuous reefs. There were slight changes in fish abundance and significant changes in fish diversity on experimental, bleached branching Acropora coral plots over a period of one year. While fish abundance on one site increased shortly after a bleaching event, 6 years later fish abundance had decreased significantly. Conversely, coral reef communities in northern Tanzania had changed little over an 8-year period, with minor changes associated with the 1997-98 ENSO and the presence or absence of fisheries management. The coral reefs in the region were found to show high variability in community structure and responses of associated fish and invertebrate communities. The findings of this thesis indicate the importance of habitat structure and spatial arrangement of reefs, the detrimental effects of coral bleaching, and the possibility that some reefs and some (generalist) reef fish taxa may exhibit resilience to climate change.At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3: Manuscript. Paper 4: Manuscript.
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Escalle, Lauriane. "Spatio-temporal interactions between whale sharks, cetaceans and tropical tuna purse-seine fisheries, within a conservation perspective, in the Atlantic and Indian Oceans." Thesis, Montpellier, 2016. http://www.theses.fr/2016MONTT125/document.
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Dans le cadre de l’Approche Ecosystémique des Pêches (AEP), il est nécessaire d’évaluer l’impact de la pêche thonière tropicale à la senne sur les espèces ciblées et sur les espèces accessoires. Parmi ces dernières, les espèces de la mégafaune, telles que des requins, raies, cétacés, tortues, oiseaux marins, sont souvent emblématiques et vulnérables. Les thoniers senneurs tropicaux recherchent activement à la surface de l’eau tout indice de la présence de bancs de thon (e.g. oiseaux, objets flottants, baleines, dauphins ou requins baleines). Dans l’est de l’océan Atlantique et l’ouest de l’océan Indien, les deux modes de pêches principaux sont les captures de thons en bancs libres et celles sur bancs associés à un objet flottant, naturel ou artificiel, rassemblés ici sur sous le terme de dispositif de concentration de poisson (DCP). Les calées associées aux requins baleines et aux cétacés sont toutefois peu étudiées. L’objectif de cette thèse est donc d’analyser les co-occurrences et/ou interactions spatio-temporelles entre requins baleines, cétacés et pêche thonière à la senne, dans une perspective de conservation de l’écosystème. Ce travail, basé sur des données de livres de bord et d’observateurs scientifiques embarqués, a montré que la co-occurrence pêche thonière/ mégafaune se localise dans des strates spatio-temporelles relativement précises: i) du Gabon à l’Angola (avril–septembre), ii) dans le Canal du Mozambique (juin–septembre) et iii) à l’est des Seychelles (avril–septembre). Les baleines et requins baleines étant planctivores, la co-occurrence avec la pêche à la senne est principalement liée à une forte productivité primaire (appréhendée à travers des proxys tels que la concentration en chlorophylle-a). De plus, les calées sur ces deux groupes étaient assez élevées avant 2000 (jusqu’à 20% des calées), et qu’elles sont moins fréquentes aujourd’hui (AC3 et 1,5% des calées associées à des baleines et des requins baleines, respectivement). L’impact de la pêche à la senne sur ces espèces semble relativement faible au regard du taux de mortalité apparente de 1,4% pour les requins baleines et 5,6% pour les cétacés. Des marquages satellites réalisés sur les requins baleines, confirment ces observations sur le plus long terme, mais la taille de l’échantillon limite la formulation de conclusions définitives. Concernant les dauphins, bien que présents sur les zones de pêche, ils interagissent très peu avec celle-ci, soulignant ainsi une différence majeure avec l’océan Pacifique est où ce mode de pêche est majoritaire. La diversité spécifique des espèces cible et accessoire associées aux calées sur mégafaune a également été étudiée. Les requins baleines sont associés aux listaos et à l’albacore (dans une large gamme de tailles), alors que les baleines le sont principalement à de gros albacores. De plus, la capture accessoire associée à ces deux groupes de mégafaune est relativement faible et dominée par le requin soyeux et la diversité spécifique est proche de celle trouvée sous les bancs libres de thons. Enfin les effets de mesures de conservation vis-à-vis de la mégafaune encerclée ou de mesures de gestion de l’effort de pêche, notamment les moratoires sur DCP réelles ou simulées (e.g. moratoires élargis), ont été analysés. Les premières ont eu un effet limité en terme de captures cibles et accessoires, alors que les moratoires impactent peu le nombre de calées associés à la mégafaune, ceci en raison du décalage spatio-temporel des co-occurrences. Cependant des moratoires élargis pourraient être bénéfiques pour les thons juvéniles et certaines espèces associées. Par l’analyse quantitative des interactions entre la pêche thonière à la senne et la mégafaune, cette thèse apporte des connaissances essentielles sur les espèces étudiées dans le cadre de la mise en place d’une AEP, applicable à la pêche thonière tropicaleIn the frame of the Ecosystem Approach to Fishery (EAF) management, impact of the tropical tuna purse-seine fishery on targeted and incidentally captured species should be investigated. They may include megafauna species, such as sharks, rays, cetaceans, turtles or sea birds, which often are emblematic and vulnerable species. Tropical tuna purse-seiners actively search, at the surface of the sea, for clues indicating the presence of tuna schools (e.g. birds, floating objects, whales, dolphins or whale sharks). In the eastern Atlantic and western Indian Oceans, the main two fishing modes are sets on free swimming tuna schools and schools associated to natural or artificial floating objects, thereafter called Fish Aggregating Device (FAD). However dedicated studies on fishing sets associated to whale sharks and cetaceans are still lacking. The aim of this thesis is therefore, using logbook and scientific onboard observer data, to investigate the spatio-temporal co-occurrences and/or interactions between whale sharks, cetaceans and the tuna purse-seine fishery within an ecosystem conservation perspective. This work underlines that the megafauna/ fishery co-occurrence occurs in specific spatio-temporal strata: i) Gabon to Angola (April–September), ii) the Mozambique Channel (June–September), and iii) East of Seychelles (April–September). As baleen whales and whale sharks are filter feeders, the co-occurrence with the purse-seine fishery was mostly linked to highly productive environments (i.e. using proxys including chlorophyll-a concentration). In addition fishing sets involving megafauna were relatively high before 2000 (up to 20% of the sets), but are nowadays less frequent (AC3 and 1.5% of the sets associated to baleen whales and whale sharks). The purse-seine fishery appears to have a relatively low impact on megafauna species with mortality rates of 1.4% for whale sharks and 5.6% for cetaceans. Whale shark satellite tagging also confirms these results on the longer term, but the low sample size precludes any final conclusion. While dolphins are present in fishing areas, very few interactions with the fishery was detected, which highlights the striking difference with the eastern Pacific Ocean where half the sets are associated to dolphin herds. In addition, the diversity of targeted and bycatch species captured under whale shark and baleen whale sets was also investigated. Whale sharks are principally associated to skipjack and yellowfin (of various sizes) tunas and baleen whales mostly to large yellowfin tuna. In addition, bycatch species associated to these two megafauna groups was relatively low and dominated by the silky shark, and bycatch diversity was close to the one found for free swimming tuna schools. Finally, real and/or simulated encircled megafauna conservation measures or fishing effort management measures (especially FAD moratoria including larger ones) were investigated. The first ones were found to have limited consequences on tuna catch and bycatch. Conversely FAD moratoria had limited impacts on the number of megafauna associated fishing sets, due to the fact that the main spatio-temporal strata of megafauna and FAD sets differ. However larger and longer moratoria could be beneficial for juvenile tuna and some bycatch species. Overall, this thesis has lead to increase the knowledge on megafauna/ fishery interactions, essential in the general framework of setting up an EAF in the tropical tune purse-seine fishery
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Rosenberg, J. Shoshana. "Study of Prestige and Resource Control Using Fish Remains from Cathlapotle, a Plankhouse Village on the Lower Columbia River." PDXScholar, 2015. https://pdxscholar.library.pdx.edu/open_access_etds/2356.
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Social inequality is a trademark of Northwest Coast native societies, and the relationship between social prestige and resource control, particularly resource ownership, is an important research issue on the Northwest Coast. Faunal remains are one potential but as yet underutilized path for examining this relationship. My thesis work takes on this approach through the analysis of fish remains from the Cathlapotle archaeological site (45CL1). Cathlapotle is a large Chinookan village site located on the Lower Columbia River that was extensively excavated in the 1990s. Previous work has established prestige distinctions between houses and house compartments, making it possible to examine the relationship between prestige and the spatial distribution of fish remains. In this study, I examine whether having high prestige afforded its bearers greater access to preferred fish, utilizing comparisons of fish remains at two different levels of social organization, between and within households, to determine which social mechanisms could account for potential differences in access to fish resources. Differential access to these resources within the village could have occurred through household-level ownership of harvesting sites or control over the post-harvesting distribution of food by certain individuals.
Previous work in this region on the relationship between faunal remains and prestige has relied heavily on ethnohistoric sources to determine the relative value of taxa. These sources do not provide adequate data to make detailed comparisons between all of the taxa encountered at archaeological sites, so in this study I utilize optimal foraging theory as an alternative means of determining which fish taxa were preferred. Optimal foraging theory provides a universal, quantitative analytical rule for ranking fish that I was able to apply to all of the taxa encountered at Cathlapotle. Given these rankings, which are based primarily on size, I examine the degree to which relative prestige designations of two households (Houses 1 and 4) and compartments within one of those households (House 1) are reflected in the spatial distribution of fish remains. I also offer a new method for quantifying sturgeon that utilizes specimen weight to account for differential fragmentation rates while still allowing for sturgeon abundance to be compared to the abundances of other taxa that have been quantified by number of identified specimens (NISP).
Based on remains recovered from 1/4" mesh screens, comparisons between compartments within House 1 indicate that the chief and possibly other elite members of House 1 likely had some control over the distribution of fish resources within their household, taking more of the preferred sturgeon and salmon, particularly more chinook salmon, for themselves. Comparisons between households provide little evidence to support household-based ownership of fishing sites. A greater abundance of chinook salmon in the higher prestige House 1 may indicate ownership of fishing platforms at major chinook fisheries such as Willamette Falls or Cascades Rapids, but other explanations for this difference between households are possible. Analyses of a limited number of bulk samples, which were included in the study in order to examine utilization of very small fishes, provided insufficient data to allow for meaningful intrasite comparisons. These data indicate that the inhabitants of Cathlapotle were exploiting a broad fish subsistence base that included large numbers of eulachon and stickleback in addition to the larger fishes. This study provides a promising approach for examining prestige on the Northwest Coast and expanding our understanding of the dynamics between social inequality and resource access and control.
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Braje, Todd J. "Archaeology, human impacts, and historical ecology on San Miguel Island, California /." view abstract or download file of text, 2007. http://proquest.umi.com/pqdweb?did=1404340481&sid=1&Fmt=2&clientId=11238&RQT=309&VName=PQD.
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Thesis (Ph. D.)--University of Oregon, 2007.Typescript. Includes vita and abstract. Includes bibliographical references (leaves 339-383). Also available for download via the World Wide Web; free to University of Oregon users.
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Maufroy, Alexandra. "Drifting Fish Aggregating Devices of the Atlantic and Indian Oceans : modalities of use, fishing efficiency and potential management." Thesis, Montpellier, 2016. http://www.theses.fr/2016MONTT150/document.
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Depuis le milieu des années 1990, l’utilisation de Dispositifs de Concentration de Poissons (DCP), des objets artificiels spécifiquement mis à l’eau pour agréger des bancs de poissons, est devenue de plus en plus importante pour la pêche au thon tropical à la senne. Cette utilisation massive des DCP, qui s’accompagne d’une utilisation massive de dispositifs de suivi comme les balises GPS et les balises échosondeurs, est aujourd’hui source d’inquiétude pour les stocks de thons, les prises accessoires mais aussi pour le fonctionnement des écosystèmes pélagiques. Cependant, les modalités d’utilisation des DCP et des balises GPS qui servent à les suivre restent mal connues, ce qui complique considérablement l’évaluation et la gestion des impacts de ces pratiques de pêche. Afin d’améliorer les connaissances actuelles de la pêcherie, les positions des balises GPS utilisées par les 3 armements français dans les océans Atlantique et Indien, constituant une part significative des DCP utilisés dans ces deux océans, ont été analysées. Ces données ont été combinées avec des multiples sources d’information : les livres de bord, les trajectoires VMS des senneurs français ainsi que des entretiens avec les patrons français. Elles nous permettent de mieux comprendre les stratégies de mise à l’eau des DCP et des balises, d’estimer le nombre d’objets flottants utilisés par les flottes de senneurs dans les océans Atlantique et Indien, de mesurer la contribution des DCP et des navires auxiliaires à l’efficacité de pêche des senneurs, d’identifier des destructions potentielles d’habitats par les DCP échoués and pour finir de proposer des solutions de gestion pour la pêcherie. Les résultats montrent une grande saisonnalité dans les mises à l’eau des deux océans, une croissance rapide du nombre de balises GPS au cours des 7 dernières années puisqu’elle est multipliée par 4.2 dans l’Océan Indien et 7 dans l’Océan Atlantique, des dommages possibles causés à des écosystèmes côtiers fragiles avec une probabilité d’échouage de l’ordre de 10% et finalement une augmentation de l’efficacité de pêche entre 2003 et 2014 de l’ordre de 3.8-18.8% dans l’Océan Atlantique et 10.7%-26.3% dans l’Océan Indien. Les entretiens avec les capitaines des senneurs soulignent la nécessité d’une gestion plus efficace de la pêcherie, avec entre autres l’instauration de quotas, une régulation de la capacité de la flotte de senneurs et un meilleur suivi des navires auxiliaires. Les résultats obtenus constituent les premières étapes nécessaires à une meilleure gestion de la pêche sous objet flottantSince the mid 1990s, the use of drifting Fish Aggregating Devices (dFADs) by purse seiners, artificial objects specifically designed to aggregate fish, has become an important mean of catching tropical tunas. In recent years, the massive deployments of dFADs, as well as the massive use of tracking devices on dFADs and natural floating objects, such as GPS buoys, have raised serious concerns for tropical tuna stocks, bycatch species and pelagic ecosystem functioning. Despite these concerns, relatively little is known about the modalities of GPS buoy tracked objects use, making it difficult to assess and manage of the impacts of this fishing practice. To fill these knowledge gaps, we have analyzed GPS buoy tracks provided by the three French fishing companies operating in the Atlantic and the Indian Oceans, representing a large proportion of the floating objects monitored by the French fleet. These data were combined with multiple sources of information: logbook data, Vessel Monitoring System (VMS) tracks of French purse seiners, information on support vessels and Local Ecological Knowledge (LEK) of purse seine skippers to describe GPS buoy deployment strategies, estimate the total number of GPS buoy equipped dFADs used in the Atlantic and Indian Oceans, measure the contribution of strategies with FOBs and support vessels to the fishing efficiency of tropical tuna purse seiners, identify potential damages caused by lost dFADs and finally to propose management options for tropical tuna purse seine FOB fisheries. Results indicate clear seasonal patterns of GPS buoy deployment in the two oceans, a rapid expansion in the use of dFADs over the last 7 years with an increase of 4.2 times in the Indian Ocean and 7.0 times in the Atlantic Ocean, possible damages to fragile coastal ecosystems with 10% of GPS buoy tracks ending with a beaching event and an increased efficiency of tropical tuna purse seine fleets from 3.9% to 18.8% in the Atlantic Ocean over 2003-2014 and from 10.7% to 26.3% in the Indian Ocean. Interviews with purse seine skippers underlined the need for a more efficient management of the fishery, including the implementation of catch quotas, a limitation of the capacity of purse seine fleets and a regulation of the use of support vessels. These results represent a first step towards better assessment and management of purse seine FOB fisheries
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Mablouké, Cécile. "Étude des ratios isotopiques du carbone et de l'azote de la matière organique particulaire et des muscles de poissons d'intérêt commercial d'écosystèmes côtiers tropicaux du sud-ouest de l'océan Indien : contribution à l'étude de leur fonctionnement." Thesis, La Réunion, 2013. http://www.theses.fr/2013LARE0017/document.
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L'objectif de cette thèse est l'étude du régime alimentaire de poissons côtiers commerciaux et la compréhension de l'utilité des isotopes stables du carbone (δ13C) et de l'azote (δ15N) dans l'étude des niches trophiques et de l'occupation des habitats côtiers par les poissons dans le sud-ouest de l'océan Indien. Dans la Baie de La Possession, les espèces représentatives des récifs artificiels immergés en 2003 (Luljanus kasmira, Priacanthus hamrur et Selar crumenophthalmus) ingèrent surtout des proies pélagiques et partitionnent leurs niches trophiques afin de limiter la compétition. Les valeurs de δ15N sont positivement corrélées avec la taille des poissons, traduisant une contribution croissante des larves de poissons au régime alimentaire. Les isotopes stables de la matière organique particulaire (MOP) ont été analysés à microéchelle (< 10 km) dans la Baie de La Possession, à mésoéchelle (10aines de km) autour de La Réunion et, pour les muscles de poissons à macroéchelle (l00aines de km) le long,du plateau .des Mascareignes.et du cana1 du Mozambique. À microéchelle, le δ15N de la MOP ne varie pas; à mésoechelle, Il existe un enrichissement significatif en 15N dans le sud-ouest de l'île; à macroéchelle, les muscles des poissons s'enrichissent progressivement en 15N vers le nord. À microéchelle, la MOP est enrichie en 13C à faible profondeur; à mésoéchelle, les stations de l'est sont enrichies en 13C ; à macroéchelle, aucune tendance n'est observée. Ainsi, l'utilité des isotopes stables du carbone pour l'étude de l'utilisation des habitats côtiers est limitée à méso- et macroéchelle et les isotopes stables de l'azote constituent un outil plus pertinent à macroéchelleThe aim of this thesis was to study the feeding habits of coastal fish species of commercial interest andto use stable isotopes of carbon (δ13C) and nitrogen (δ15N) to investigate the trophic niches of fish and their use of coastal habitats in the south-west Indian Ocean. In the Bay of La Possession, the species among the most abundant around the artificial reefs immersed in 2003 (Luljanus kasmira, Priacanthus hamrur and Selar crumenophthalmus) feed essentially on pelagic prey and partition their trophic niche to limit interspecific competition. There was also a positive correlation between fish size and muscle δ15N values due to fish larvae contributing more to the diet of fish with age. The stable isotopie composition of the particulate organic matter (POM) was measured at the microscale (< 10 km) in the Bay of La Possession, the mesoscale (10's of km) around Reunion Island and, for the fish muscles, at the macroscale 100’s of km) along the Mascarene plateau and the Mozambique channel. At microscale, POM δ15N values do not show any spatial variability; at mesoscale, POM is 15N-enriched in the south-west of Reunion Island; at macroscale, fish muscles are gradually 15N-enriched towards the north. At microscale, POM shows a 13C-enrichment on the shallowest station; at mesoscale, stations on the east coast of the island are 13C-enriched compared to the west; at macroscale, POMδ13C values are not significantly correlated with latitude. Thus, the stable isotopes of carbon do not seem to be appropriate for the study of fish coastal habitat use at the meso- and macroscale, and the stable isotopes of nitrogen represent a better indicator of fish habitat use at the macroscale
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Lavergne, Edouard. "Biodiversité des poissons estuariens de l'Ile de Socotra (Nord-Ouest de l'Océan Indien) : du peuplement ichtyologique au fonctionnement des populations de Terapon jarbua." Thesis, Brest, 2012. http://www.theses.fr/2012BRES0093/document.
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La compréhension de la connectivité entre les nourriceries estuariennes et les habitats marins est fondamentale pour l'étude de la dynamique des peuplements et des populations de poissons et pour la conception de stratégies efficaces de conservation et de gestion des pêches. Le but de ce travail était donc de fournir une première référence faunistique et écologique des poissons des estuaires et du lagon de l'île de Socotra (Nord-Ouest de l'Océan Indien) pour les gestionnaires de la zone côtière, avec un accent particulier sur le fonctionnement des populations d'une espèce sentinelle: Terapon jarbua. Dans cette étude, une approche multidisciplinaire a été développée afin de comprendre le fonctionnement et l'importance des estuaires (TOCE's : Temporarily Open / Closed Estuaries) et du lagon de l'île de Socotra pour les poissons marins. Différents outils de la biologie et de la chimie (taxonomie, écologie, phylogéographie, génétique des populations, microstructure et microchimie des otolithes) ont été utilisés et les principales conclusions de ce travail sont les suivantes: 1) Les estuaires de Socotra sont composés de 64 espèces dans 30 familles, un chiffre élevé par rapport aux normes régionales. La comparaison avec les inventaires faunistiques d'Afrique du Sud et du Yémen suggère que Socotra joue le rôle de tremplin biogéographique, en permettant la connexion d'une grande variété de groupes taxonomiques provenant de différentes unités biogéographiques. De plus 33 des 64 espèces recensées sont considérées comme importantes pour l'économie locale, soulignant l'importance primordiale des estuaires comme sites de fraie et nourriceries, pour le fonctionnement durable des services écosystémiques. 2) La phylogéographie et la structure génétique des populations de T. jarbua ont été analysées considérant des marqueurs de type Cytochrome c Oxydase sous-unité I et microsatellites. Une différenciation génétique élevée et significative a été observée à l'échelle de l'Indo-Ouest Pacifique. Trois groupes de populations ont pu être identifiés, le groupe du Nord-Ouest de l'Océan Indien (Socotra, Yémen et Iran), le groupe de l'Ouest de l'Inde et le groupe de la Mer de Chine. Cependant, les grandes différences nucléotidiques observées soulèvent certaines questions concernant l'identification de l'espèce et suggèrent que T. jarbua pourrait être en réalité un complexe d'espèces, en dépit du fait que la coloration caractéristique de T. jarbua facilite son identification. A l'échelle plus restreinte du Nord-Ouest de l'Océan Indien, une expansion récente de la population de T. jarbua après des extinctions locales au cours des glaciations du Pléistocène pourrait expliquer la faible mais significative différenciation génétique. Le génotypage des marqueurs microsatellites souligne une différenciation génétique relativement élevée et significative entre les estuaires, sur le secteur Socotra-Yémen. Si la distance géographique n'est pas un facteur structurant majeur des populations de T. jarbua dans la région du Golfe d'Aden, le lien étroit entre les juvéniles T. jarbua et les TOCE, ainsi que les phénomènes d'ouverture associés à de possibles goulots d'étranglement démographiques dans ces systèmes côtiers, peuvent expliquer la mise en place d'une différenciation génétique locale significative entre les estuaires. Bien que l'environnement dynamique de la région puisse limiter la différenciation génétique, la courte durée du stade larvaire de cette espèce (25 jours estimés par la lecture des microstructures de l'otolithe) et la possible rétention des larves dans certains secteurs peuvent réduire l'homogénéisation à plus grande échelle géographique. 3) Les analyses de la composition élémentaire des nucleus d'otolithes suggèrent l'existence de plusieurs zones de fraie marines ; ces données confrontées aux résultats des investigations en génétique des populations suggèrent un modèle régional de métapopulation composée de sous-populations ouvertes…Understanding connectivity between estuarine nurseries and marine habitats is fundamental to explore fish population dynamics and to the design of effective conservation and fisheries management strategies. The aim of this work was to provide the first faunistic and ecological baseline of Socotra Island (North-Western Indian Ocean) estuaries and lagoon fishes for governmental coastal managers and decision makers, with a particular focus on the population functioning of a sentinel species: Terapon jarbua. In this study, a multidisciplinary approach was developed to understand the functioning and importance of Socotra estuaries (TOCE's: Temporarily Open / Close Estuaries) and lagoons for marine fishes. Several biological and chemical tools (taxonomy, ecology, phylogenetics, population genetics, otolith microstructure, otolith microchemistry) were used and the main findings of this work are as follows: 1) Socotra estuaries are composed of 64 species in 30 families, a high figure by regional standards. The comparison with faunistic records from South Africa and Yemen mainland provides further support to Socotra's function as a biogeographic "stepping stone" for certain species. Moreover 33 out of the 64 recorded species were considered as relevant species for the local economy. This underscores the paramount importance of these coastal water bodies as spawning and nursery sites and for the sustainability of vital provisioning ecosystem services. 2) The phylogeography and the genetic structure of T. jarbua populations were analyzed considering Cytochrome c Oxidase subunit I and microsatellites and underlined two patterns of genetic structure. A high and significant genetic differentiation was observed at the scale of the Indo-West Pacific. Three population clusters could be drawn, the North-Western Indian Ocean cluster (Socotra, Yemen and Iran), the West Indian Shelf cluster and the Chinese Sea cluster. However, the large number of nucleotide differences raised some issues concerning the species identification as T. jarbua might be a species complex, despite the fact that it shows a characteristic color pattern easily identifiable. At the restricted scale of the North-Western Indian Ocean, recent population expansion after local extinctions during the Pleistocene glaciations might explain small but significant genetic differentiation. Considering microsatellites, genotyping highlighted a relatively high and significant genetic differentiation between estuaries, over the Socotra-Yemen region. Geographical distance is not a major structuring factor for T. jarbua populations in the wider Gulf of Aden region. The strict link between juvenile T. jarbua and TOCE's, and the opening/closing associated with possible demographic bottlenecks, could increase the local differentiation among estuaries. Although the dynamic environment of the region driven by the monsoon system could reduce the genetic differentiation between populations, the short larval stage duration and potential larval retention in particular sectors might reduce homogenization over larger geographical scale. 3) The analysis of otolith nucleus elemental composition suggested the existence of several marine spawning grounds, thus confirming the population genetics approach suggesting a regional model of metapopulation composed of open subpopulations (i.e. multiple sources and more or less pronounced mixtures of larval flows displaying a spatio-temporal variability). In addition, transect Sr:Ba ratio analysis along the otolith growth axis showed clear pattern of post larval migrations into estuarine nurseries where individuals remain for two years. Finally, otolith edges elemental fingerprint assignation tests to nurseries were highly accurate and could conduct in the future to the assessment of the contribution level of a particular nursery to the adult population of T. jarbua as well as others ecologically or economically important species
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Cuvillier, Alexis. "Dynamique et fonctionnement des herbiers marins dans un complexe récifal anthropisé (île de la Réunion, océan Indien)." Thesis, La Réunion, 2016. http://www.theses.fr/2016LARE0037/document.
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À l'interface bentho-pélagique, les herbiers marins présentent une multitude de rôles écosystémiques. Historiquement, les scientifiques et décideurs de La Réunion se sont focalisés sur l'écosystème récifal. Néanmoins, des prairies monospécifiques à Syringodium isoetifolium sont présentes de manière pérenne (3 hectares) au sein du complexe récifal de l'Ermitage / La Saline (côte ouest). L'objectif principal de cette étude était d'apporter les premières données sur l'écologie de ces herbiers marins. Ainsi, une approche pluridisciplinaire a été développée : 1. L'étude de la dynamique spatiale du paysage herbier sur 65 ans (dès 1950), et à l'échelle saisonnière (2013-2015) qui a permis de définir le rôle majeur des forçages hydrodynamiques et de l'eutrophisation. 2. L'analyse de la productivité de l'écosystème herbier et sa réponse métabolique face à des apports nutritifs, révèle des bilans métaboliques opposés (autotrophie/hétérotrophie) en fonction des conditions environnementales, ainsi qu'un rôle de tampon sur les flux de nutriments. 3. Des analyses isotopiques (δ13C et δ15N) ont permis d'identifier les sources de matière entrant dans l'écosystème et alimentant les réseaux trophiques associés aux herbiers. L'étude a permis d'établir un lien trophique entre Holothuria leucospilota et les herbiers marins ainsi qu'un rôle essentiel dans le maintien des populations de poisson herbivores récifaux. 4. Des enquêtes locales ont révélé une méconnaissance de cet écosystème malgré leur potentiel économique et écologique. À la lumière de ces travaux de thèse, la prise en considération des herbiers marins dans la gestion du milieu marin réunionnais est nécessaireLocated at the benthos-pelagos interface, seagrass beds have many ecosystemic roles such as coastal protection or biodiversity. Historically, scientists and decision-makers at Reunion Island have been focusing on reef ecosystems. However, for several decades, monospecific (Syringodium isoetifolium) seagrass beds have been observed (3 hectares – 2013) within Ermitage / La Saline reef (West coast). The main objective of this study was to give the first data on seagrass ecology at Reunion Island. Therefore, a multi-disciplinary study was developed. First, seascape ecology of seagrasses is analyzed at decadal (since 1950) and seasonal scales (2013-2015). Physical settings (swell) and eutrophication were driving factors on the spatial dynamics of seagrass beds. Second, seagrass community metabolism and response to nutrient loads (nitrate and phosphate) show variations in metabolic budget (autotrophy to heterotrophy) and make seagrass beds a nutrient sink following the environmental conditions. Third, stable isotope analysis (δ13C and δ15N) identified sources of particulate matter entering the ecosystem and fueling food webs. The trophic roles of seagrass beds are assessed for echinoderm and herbivorous fish communities. This study highlighted a trophic link between seagrass and Holothuria leucospilota, and proved some species to be heavily dependent on seagrass ecosystem (Leptoscarus vaigiensis, Siganus sutor). Finally, interviews showed a lack of knowledge about this ecosystem despite crucial economic and ecologic roles. Considering their major functions, seagrass beds have to be considered in future management of the coastal marine systems at Reunion Island
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Walker, Emily. "De la trajectoire des prédateurs à la cartographie de leurs proies : estimation spatiale de l'activité des senneurs et des thonidés dans l'Océan indien." Phd thesis, École Nationale Supérieure des Mines de Paris, 2010. http://pastel.archives-ouvertes.fr/pastel-00552183.
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Actuellement, la distribution spatiale des thons tropicaux pêchés par les senneurs français dans l'Océan Indien est représentée à partir des données de captures et d'effort issues des livres de bord. Or ces données ne comportent qu'une position par jour et le nombre de calées réalisées pendant cette journée : l'ensemble des zones prospectées sans action de pêche, synonyme d'absence d'agrégations de thon n'est pas connu. Ces zones seraient pourtant utiles à la cartographie des abondances. Cette flottille étant équipée de systèmes VMS (Vessel Monitoring Systems), les trajectoires données par les VMS sont utilisées pour déduire du comportement des navires, les zones de présence (pêche) et d'absence (non pêche) d'agrégations de thonidés. L'objectif est donc d'estimer l'activité d'un navire à partir de sa trajectoire. L'application d'un modèle markovien permet de distinguer les activités de route, de recherche, et d'arrêt, et de pêche. Pour la majorité des sorties en mer (exceptées celles où un observateur est à bord), l'activité réelle du navire n'est pas connue (variable latente), ce qui justifie l'approche par chaînes de Markov à états cachés. Le modèle a été développé dans un contexte bayésien incluant des priors sur certains des paramètres (vitesses, angles de changement de cap et matrice de transition). Il a été calibré et validé grâce aux données collectées par des observateurs embarqués sur 10% de la flottille. Le taux d'erreur est de 10% pour des positions VMS enregistrées toutes les heures. Une fois estimée, l'activité des senneurs en chaque point de leur trajectoire a permis (1) d'obtenir des indicateurs spatiaux et temporels de l'effort de la flottille de senneurs français, et (2) d'étudier la structure spatiale des zones de présence de bancs de thons (variogrammes d'indicatrices) et d'en déduire, par cokrigeage d'indicatrices, des cartes de présence/présence potentielle/absence de thon capturable, pouvant être interprétées comme indices d'abondance de thon.
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Tomblin, David Christian. "Managing Boundaries, Healing the Homeland: Ecological Restoration and the Revitalization of the White Mountain Apache Tribe, 1933 – 2000." Diss., Virginia Tech, 2009. http://hdl.handle.net/10919/27577.
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The main argument of this dissertation is that the White Mountain Apache Tribe's appropriation of ecological restoration played a vital role in reinstituting control over knowledge production and eco-cultural resources on the Fort Apache Indian Reservation in the second half of the twentieth century. As a corollary, I argue that the shift in knowledge production practices from a paternalistic foundation to a community-based approach resulted in positive consequences for the ecological health of the Apachean landscape and Apache culture. The democratization of science and technology on the reservation, therefore, proved paramount to the reestablishment of a relatively sustainable Apache society.
Beginning with the Indian New Deal, the White Mountain Apache slowly developed the capacity to employ ecological restoration as an eco-political tool to free themselves from a long history of Euro-American cultural oppression and natural resource exploitation. Tribal restoration projects embodied the dual political function of cultural resistance to and cultural exchange with Western-based land management organizations. Apache resistance challenged Euro-American notions of restoration, nature, and sustainability while maintaining cultural identity, reasserting cultural autonomy, and protecting tribal sovereignty. But at the same time, the Apache depended on cultural exchange with federal and state land management agencies to successfully manage their natural resources and build an ecologically knowledgeable tribal workforce.
Initially adopting a utilitarian conservation model of land management, restoration projects aided the creation of a relatively strong tribal economy. In addition, early successes with trout, elk, and forest restoration projects eventually granted the Tribe political leverage when they sought to reassume control over reservation resources from the Bureau of Indian Affairs and the Fish and Wildlife Service. Building on this foundation, Apache restoration work significantly diverged in character from the typical Euro-American restoration project by the 1990s. While striving toward self-sufficiency, the Tribe hybridized tribal cultural values with Western ecological values in their restoration efforts. These projects evolved the tripartite capacity to heal ecologically degraded reservation lands, to establish a degree of economic freedom from the federal government, and to restore cultural traditions. Having reversed their historical relationship of subjugation with government agencies, the Apache currently have almost full decision-making powers over tribal eco-cultural resources.Ph. D.
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Watson, Brian T. "Population biology and fish hosts of several federally endangered freshwater mussels (Bivalvia: Unionidae) of the upper Tennessee River drainage, Virginia and Tennessee." Thesis, This resource online, 1999. http://scholar.lib.vt.edu/theses/available/etd-08222008-063606/.
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Mahé, Kélig. "Sources de variation de la forme des otolithes : Implications pour la discrimination des stocks de poissons Identifying blue whiting (Micromesistius poutassou) stock structure in the Northeast Atlantic by otolith shape analysis. Otolith shape as a valuable tool to evaluate the stock structure of swordfish Xiphias gladius in the Indian Ocean Directional bilateral asymmetry in otolith morphology may affect fish stock discrimination based on otolith shape analysis Do environmental conditions (temperature and food composition) affect otolith shape during fish early-juvenile phase? An experimental approach applied to European Seabass (Dicentrarchus labrax)." Thesis, Littoral, 2019. http://www.theses.fr/2019DUNK0539.
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L’évaluation et la gestion des populations de poissons se basent sur l'utilisation d’unités de gestion appelées « stocks halieutiques ». Pour discriminer ces stocks, la forme des otolithes, pièces calcifiées de l’oreille interne des poissons, peut être utilisée. Dans ce contexte, cette thèse s'est consacrée premièrement à l’étude de la variabilité spatio-temporelle de la forme des otolithes chez 3 espèces de poissons présentant des caractéristiques écologiques (taille, vitesse de nage, comportement dans la colonne d’eau, etc.) et des environnements biogéographiques différents. Les résultats montrent qu’il existe un gradient structurel décroissant de taille des stocks allant des espèces de grands pélagiques aux espèces démersales. Ceci est lié au fait que certaines espèces démersales comme la bogue (Boops boops) sont contraintes par la présence de barrières géographiques et de fronts hydrologiques ce qui n’est pas le cas chez les espèces pélagiques analysées (merlan bleu, Micromesistius poutassou ; Espadon, Xiphias gladius). Dans un deuxième temps, nous avons testé les effets de facteurs confondants potentiels (e.g. l’asymétrie bilatérale directionnelle, AD) sur le pouvoir discriminant de la forme des otolithes. Ainsi, nous avons montré qu'il existe chez la bogue une AD, induite par un processus de latéralisation et qui varie en amplitude et en direction selon la zone géographique étudiée. Chez la bogue, cette AD impacte les résultats d’identification des stocks par la forme qui changent en fonction de l'otolithe, droit ou gauche, utilisé. Si la forme de l’otolithe est utilisée pour discriminer les stocks halieutiques, c’est parce qu’elle reflète en particulier les conditions environnementales qu’a subi le poisson au cours de sa vie. Ainsi, dans la troisième partie de la thèse, nous avons analysé, en conditions contrôlées, les effets de la température et du taux d'acides gras polyinsaturés omega-3 (n-3 AGPI) contenus dans l’alimentation sur la morphogenèse des otolithes de bars (Dicentrachus labrax). Après la naissance, deux étapes peuvent être distinguées dans l’ontogenèse de la forme de l’otolithe avec en premier lieu un allongement qui traduit une croissance moins rapide de l’axe dorso-ventral par rapport à l’axe antéro-postérieur. Il s'en suit des modifications plus localisées avec en particulier une complexification de la zone comprise entre le rostre et l’anti-rostre a priori essentiellement liée au facteur thermique. A l’inverse, le taux de n-3 AGPI ne semble pas influencer la morphogenèse de l’otolithe. L’utilisation des degrés-jours de croissance (GDD) a permis de montrer que l’effet de la température est bien d’accélérer la morphogenèse, mais aussi de changer sa trajectoire: à valeur de GDD fixe, pour 2 températures données, les formes diffèrent. L’ensemble des résultats acquis lors de cette thèse valident l’utilisation de la forme des otolithes pour discriminer les stocks de poissons, mais souligne également le besoin de connaître précisément les sources de la variabilité morphologique des otolithes intra-stock pour pouvoir déterminer plus précisément les limites des stocks halieutiquesThe assessment and management of fish populations is based on the use of management units called fish stocks. The shape of otoliths, calcified structures of the fish's inner ear, can be used to discriminate these stocks. First, this thesis focuses on the study of the spatio-temporal variability of the otolith’s shape for three fish species with different ecological characteristics (size, swimming speed, behaviour in the water column, etc.) and biogeographical environments. The results showed that there is a decreasing structural gradient across stock sizes from large pelagic species to more localised demersal species. This is linked to the fact that some demersal species such as the bogue (Boops boops) are constrained by the presence of geographical barriers and hydrological fronts, which is not the case for the analysed pelagic species (blue whiting, Micromesistius poutassou; swordfish, Xiphias gladius). Secondly, we tested the effects of potential confounding factors (e. g. bilateral directional asymmetry, DA) on the discriminating power of an otolith’s shape. We have shown that there is a DA for bogue, induced by the lateralisation process, which varies in amplitude and direction according to the geographical area. In the bogue, this DA impacts stock identification by otolith shape, which changes according to which otolith is used (i.e. right or left). Otolith shape is useful to discriminate among fish stocks because it reflects the specific environmental conditions that fish have experienced during their lifetime. Finally, in the third part of the thesis, we analyzed, under controlled conditions, the effects of temperature and the diet content of omega-3 polyunsaturated fatty acids (n-3 PUFAs) on otolith morphogenesis for seabass (Dicentrachus labrax). After emergence, two phases can be distinguished in the ontogenesis of otolith shape with an initial elongation that reflects slower growth of the dorso-ventral axis compared to the antero-posterior axis. This leads to more localized modifications, in particular, in a more complex area between the rostrum and the anti-rostrum, which is clearly linked to the thermal regime. Conversely, the percentage of n-3 PUFAs does not appear to influence otolith morphogenesis. The use of growing degree days (GDD) has shown that the effect of temperature is to accelerate morphogenesis, but also to change its trajectory: at a fixed GDD value, for two given temperatures, the shapes differ. All the results obtained in this thesis validate the use of the otolith shape to discriminate fish stocks, but also emphasize the need to know the precise sources of morphological variability of intra-stock otoliths in order to determine more precisely the limits of fish stocks
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Pritchett, Jennifer M. "Fish assemblage variation in the Wabash River, Indiana : covariation with hydrology and substrates." 2010. http://liblink.bsu.edu/uhtbin/catkey/1610826.
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The local substrate composition of large rivers varies with local current velocity and high flow events. We evaluated effects of hydrology on local substrate variation for 28 Wabash River sites from 2005-08, and subsequent variation in fish assemblages using multivariate analyses. Sites were 500-m in length and fish were collected by boat electrofisher. Substrate collection methods were compared by way of habitat pole, developed by Ohio River Valley Sanitation Commission (ORSANCO), and substrate grabs. We characterized hydrologic variation with the Indicators of Hydrologic Alteration (IHA) software. We determined important driving variables of fish assemblages, substrates, and hydrology with Principle Components Analysis. Temporal effects of hydrology and substrate variation on taxonomic and functional fish assemblages were determined by repeated measures ANOVA. The analyses resulted in annual variation in fish assemblage structure, substrates and hydrologic variation. Significant relationships were found for fish assemblage structure, substrate variation, and hydrologic variation. . Our Mantel tests resulted in significant concordance among hydrology, local substrate variation, and fish assemblage structure variables in years 2005, 2006, and 2008, but not in 2007. These results demonstrated that Wabash River fish assemblages respond to substrate variation and substrate
variation is controlled largely by hydrology. A comparison of substrate quantification approaches demonstrated that the habitat pole and substrate grabs are both effective ways to describe fish assemblages but the costs of grabs outweigh the cost of the pole method.Department of Biology
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Crewe, Julie R. "Analysis of Mercury Concentrations in Indiana Soil to Evaluate Patterns of Long-Term Atmospheric Mercury Deposition." Thesis, 2013. http://hdl.handle.net/1805/3199.
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Indiana University-Purdue University Indianapolis (IUPUI)Mercury (Hg) has proven to be a risk to the public, mainly through the consumption of fish. Because of this, many fish consumption advisories have been issued in Indiana. Although much is known about the global cycle of mercury, little is known about how local and regional emission sources of mercury impact local and regional mercury cycling. This study’s objective was to determine the scope of mercury concentration in central Indiana by using a broad grid of soil mercury measurements. Sampling was designed to capture the net retained mercury content in soils, and to determine whether spatial patterns in exist in soil mercury contents that could be related to emission sources of mercury and post-emission transport patterns from wind. Results from this study revealed significant differences in mercury concentrations for soils in central Indiana. The core of the study area, concentrated in the urban area of Indianapolis, exhibited soil mercury contents that were 20 times higher than values in the outskirts of the study area. The spatial pattern resembled a bulls-eye shape centered on Indianapolis, and with comparison to the reported Hg emission from local sources, including a coal-fired power plant, indicates a strong regional deposition signal linked to those emission sources but marked by wind-driven transport to the northeast. This effect of local emission sources resulting in local deposition indicates that limiting mercury emissions will have a net beneficial impact on local environmental quality and human health.