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1
Minns, Charles K. "Allometry of home range size in lake and river fishes". Canadian Journal of Fisheries and Aquatic Sciences 52, n. 7 (1 luglio 1995): 1499–508. http://dx.doi.org/10.1139/f95-144.
Testo completoAbstract (sommario):
A data set assembled from published literature supported the hypotheses that (i) home range size increases allometrically with body size in temperate freshwater fishes, and (ii) fish home ranges are larger in lakes than rivers. The allometric model fitted was home range = A∙(body size)B. Home ranges in lakes were 19–23 times larger than those in rivers. Additional analyses showed that membership in different taxonomic groupings of fish, the presence–absence of piscivory, the method of measuring home range, and the latitude position of the water bodies were not significant predictive factors. Home ranges of freshwater fish were smaller than those of terrestrial mammals, birds, and lizards. Home ranges were larger than area per fish values derived by inverting fish population and assemblage density–size relationships from lakes and rivers and territory–size relationships in stream salmonids. The weight exponent (B) of fish home range was lower than values reported for other vertebrates, 0.58 versus a range of 0.96–1.14. Lake–river home range differences were consistent with differences reported in allometric models of freshwater fish density and production.
2
Welsh, J. Q., C. H. R. Goatley e D. R. Bellwood. "The ontogeny of home ranges: evidence from coral reef fishes". Proceedings of the Royal Society B: Biological Sciences 280, n. 1773 (22 dicembre 2013): 20132066. http://dx.doi.org/10.1098/rspb.2013.2066.
Testo completoAbstract (sommario):
The concept of home ranges is fundamental to ecology. Numerous studies have quantified how home ranges scale with body size across taxa. However, these relationships are not always applicable intraspecifically. Here, we describe how the home range of an important group of reef fish, the parrotfishes, scales with body mass. With masses spanning five orders of magnitude, from the early postsettlement stage through to adulthood, we find no evidence of a response to predation risk, dietary shifts or sex change on home range expansion rates. Instead, we document a distinct ontogenetic shift in home range expansion with sexual maturity. Juvenile parrotfishes displayed rapid home range growth until reaching approximately 100–150 mm length. Thereafter, the relationship between home range and mass broke down. This shift reflected changes in colour patterns, social status and reproductive behaviour associated with the transition to adult stages. While there is a clear relationship between body mass and home ranges among adult individuals of different species, it does not appear to be applicable to size changes within species. Ontogenetic changes in parrotfishes do not follow expected mass–area scaling relationships.
3
Hill, Jennifer, e Gary D. Grossman. "Home Range Estimates for Three North American Stream Fishes". Copeia 1987, n. 2 (13 maggio 1987): 376. http://dx.doi.org/10.2307/1445773.
Testo completo
4
Farmer, Nicholas A., e Jerald S. Ault. "Modeling Coral Reef Fish Home Range Movements in Dry Tortugas, Florida". Scientific World Journal 2014 (2014): 1–14. http://dx.doi.org/10.1155/2014/629791.
Testo completoAbstract (sommario):
Underestimation of reef fish space use may result in marine reserves that are too small to effectively buffer a portion of the stock from fishing mortality. Commonly used statistical home range models, such as minimum convex polygon (MCP) or 95% kernel density (95% KD) methods, require the exclusion of individuals who move beyond the bounds of the tracking study. Spatially explicit individual-based models of fish home range movements parameterized from multiple years of acoustic tracking data were developed for three exploited coral reef fishes (red grouperEpinephelus morio, black grouperMycteroperca bonaci, and mutton snapperLutjanus analis) in Dry Tortugas, Florida. Movements were characterized as a combination of probability of movement, distance moved, and turning angle. Simulations suggested that the limited temporal and geographic scope of most movement studies may underestimate home range size, especially for fish with home range centers near the edges of the array. Simulations provided useful upper bounds for home range size (red grouper:2.28±0.81 km2MCP,3.60±0.89 km2KD; black grouper:2.06±0.84 km2MCP,3.93±1.22 km2KD; mutton snapper:7.72±2.23 km2MCP,6.16±1.11 km2KD). Simulations also suggested that MCP home ranges are more robust to artifacts of passive array acoustic detection patterns than 95% KD methods.
5
Eble, Jeff A., Luiz A. Rocha, Matthew T. Craig e Brian W. Bowen. "Not All Larvae Stay Close to Home: Insights into Marine Population Connectivity with a Focus on the Brown Surgeonfish (Acanthurus nigrofuscus)". Journal of Marine Biology 2011 (2011): 1–12. http://dx.doi.org/10.1155/2011/518516.
Testo completoAbstract (sommario):
Recent reports of localized larval recruitment in predominately small-range fishes are countered by studies that show high genetic connectivity across large oceanic distances. This discrepancy may result from the different timescales over which genetic and demographic processes operate or rather may indicate regular long-distance dispersal in some species. Here, we contribute an analysis of mtDNA cytochromebdiversity in the widely distributed Brown Surgeonfish (Acanthurus nigrofuscus;N=560), which revealed significant genetic structure only at the extremes of the range (ΦCT=0.452;P<.001). Collections from Hawaii to the Eastern Indian Ocean comprise one large, undifferentiated population. This pattern of limited genetic subdivision across reefs of the central Indo-Pacific has been observed in a number of large-range reef fishes. Conversely, small-range fishes are often deeply structured over the same area. These findings demonstrate population connectivity differences among species at biogeographic and evolutionary timescales, which likely translates into differences in dispersal ability at ecological and demographic timescales. While interspecific differences in population connectivity complicate the design of management strategies, the integration of multiscale connectivity patterns into marine resource planning will help ensure long-term ecosystem stability by preserving functionally diverse communities.
6
Nash, Kirsty L., Justin Q. Welsh, Nicholas A. J. Graham e David R. Bellwood. "Home-range allometry in coral reef fishes: comparison to other vertebrates, methodological issues and management implications". Oecologia 177, n. 1 (26 novembre 2014): 73–83. http://dx.doi.org/10.1007/s00442-014-3152-y.
Testo completo
7
Haine, Olivia S., Peter V. Ridd e Richard J. Rowe. "Range of electrosensory detection of prey by Carcharhinus melanopterus and Himantura granulata". Marine and Freshwater Research 52, n. 3 (2001): 291. http://dx.doi.org/10.1071/mf00036.
Testo completoAbstract (sommario):
Elasmobranch fishes have a well developed electrosense that is used for prey detection. Research into the nature of bioelectric cues emitted by prey has, however, been neglected, and consequently the spatial context in which the electrosense operates to detect and home in on prey is not completely understood. This study provided data on both ac and dc electric potentials produced by teleost, crustacean and bivalve prey, as well as measured the decay rates of electric field strength with distance. The electrosensitivity of two tropical elasmobranch species was calculated to be ~4 nV cm–1, from which it was calculated that these predators probably detect their prey at a range of ~0. 25 m.
8
Barrett, NS. "Short- and long-term movement patterns of six temperate reef fishes (Families Labridae and Monacanthidae)". Marine and Freshwater Research 46, n. 5 (1995): 853. http://dx.doi.org/10.1071/mf9950853.
Testo completoAbstract (sommario):
Movement patterns were studied on a 1-ha isolated reef surrounding Arch Rock in southern Tasmania. Short-term movements were identified from diver observations, and interpretation of long-term movements involved multiple recaptures of tagged individuals. Visual observations indicated that the sex-changing labrids Notolabrus tetricus, Pictilabrus laticlavius and Pseudolabrus psittaculus were all site-attached, with females having overlapping home ranges and males being territorial. In the non-sex-changing labrid Notolabrus fucicola and in the monacanthids Penicipelta vittiger and Meuschenia australis, there was no evidence of territorial behaviour and 1-h movements were in excess of the scale of the study. The long-term results indicated that all species were permanent reef residents, with most individuals of all species except M. australis always being recaptured within a home range of 100 m × 25 m or less. Only 15% of individuals of M. australis were always recaptured within this range category. The natural habitat boundary of open sand between the Arch Rock reef and adjacent reefs appeared to be an effective deterrent to emigration. The use of natural boundaries should be an important consideration in the design of marine reserves where the aim is to minimize the loss of protected species to adjacent fished areas.
9
Crook, David A., Wayne M. Koster, Jed I. Macdonald, Simon J. Nicol, Chris A. Belcher, David R. Dawson, Damien J. O'Mahony, Danny Lovett, Adam Walker e Lucas Bannam. "Catadromous migrations by female tupong (Pseudaphritis urvillii) in coastal streams in Victoria, Australia". Marine and Freshwater Research 61, n. 4 (2010): 474. http://dx.doi.org/10.1071/mf09170.
Testo completoAbstract (sommario):
Understanding migratory requirements is critical for the conservation of diadromous fishes. Tupong (Pseudaphritis urvillii) are diadromous fishes found in freshwater and estuarine regions of south-eastern Australia. Previous studies have hypothesised that mature female tupong undertake downstream spawning migrations from freshwater to the estuary or sea, with a compensatory return of juveniles, and possibly spent fish, back upstream. We applied acoustic telemetry to test this hypothesis. We tagged 55 female tupong in two river systems in Victoria, Australia, and tracked movements for 4- to 6-month periods over 2 years. Thirty-one fish undertook rapid downstream migrations and then appeared to move through the estuary and out to sea between May and August in each year. Migration was associated with relatively high river discharges, and movement from the estuary to the sea tended to occur most frequently during intermediate moon phases. Low rates of movement between September and April suggested that tupong inhabited restricted home ranges outside of the spawning season. The apparently disparate migratory patterns of female (catadromous) and male (non-diadromous) tupong are rare amongst fishes globally. Differential exertion of a range of selective pressures may have resulted in the evolution of sexual differences in migratory modes in this species.
10
Bryars, Simon, Paul Rogers, Charlie Huveneers, Nicholas Payne, Ian Smith e Bryan McDonald. "Small home range in southern Australia's largest resident reef fish, the western blue groper (Achoerodus gouldii): implications for adequacy of no-take marine protected areas". Marine and Freshwater Research 63, n. 6 (2012): 552. http://dx.doi.org/10.1071/mf12016.
Testo completoAbstract (sommario):
No-take marine protected areas (MPAs) represent an effective biodiversity conservation tool for a range of species including resident reef fishes that are intrinsically vulnerable to overfishing and other localised impacts. The western blue groper (Achoerodus gouldii) is the largest permanent-resident reef teleost in southern Australian waters and has the second-oldest recorded age of any labrid at 70 years. Acoustic telemetry was used to investigate whether adult A. gouldii can be effectively protected within adequately sized no-take MPAs. Ten passive acoustic receivers tracked the movements of 15 A. gouldii individuals (69–112-cm total length; 7–31-kg weight) at a site off north-western Kangaroo Island, South Australia. Most of the fish displayed high site fidelity (91–100% residence time for 10 of the 11 fish with useful data) for a narrow strip of fringing coastal reef (~1-km length by ~40-m width) throughout a 12-month period. Mean home-range along-shore length and area were estimated at 1076 ± 83 m (s.e.), and 45 188 ± 3497 m2, respectively (n = 11 fish with useful data). Comparison with other resident temperate-reef teleosts indicated no relationship between fish length and home-range area, and that A. gouldii has a relatively small home range. The high site fidelity and small home range of adult A. gouldii individuals makes localised populations amenable to a high level of protection within no-take MPAs.
11
Weir, Richard D., Alton S. Harestad e Fraser B. Corbould. "Home Ranges and Spatial Organization of Fishers, Martes pennanti, in Central British Columbia". Canadian Field-Naturalist 123, n. 2 (1 aprile 2009): 126. http://dx.doi.org/10.22621/cfn.v123i2.690.
Testo completoAbstract (sommario):
We described the size and spatial arrangement of aggregate and seasonal home ranges for 17 radio-tagged resident Fishers (Martes pennanti) that were >1.5 years old in two areas of central British Columbia during 1990-1993 and 1996-2000. We estimated home range size for each Fisher from the 95% isopleth of the utilization distribution generated using a fixed kernel model with smoothing selected by least-squares cross-validation (95% FK). For comparison to previous studies, we also calculated the minimum convex polygon estimate of home range size (MCP) for each animal. The aggregate home ranges (95% FK) of female Fishers (mean = 37.9 km², SD = 18.5, range = 10.5 – 81.2, n = 11) were significantly smaller than those of males (mean = 161.3 km², SD = 100.0, range = 46.0 – 225.2, n = 3; P = 0.019). We observed minor overlap among 95% FK home ranges of Fishers of the same sex, but considerable overlap among home ranges of males and females. Home ranges (95% FK or MCP) that we observed in central British Columbia were larger than those reported elsewhere in North America, particularly for males. We suggest that the distribution of resources for Fishers may occur at lower gross densitiesin central British Columbia than in other portions of the Fisher’s range and that suitable habitat in which Fishers can establish home ranges is not found uniformly across the landscape.
12
Page, Timothy J., Mark I. Stevens, Mark Adams, Ralph Foster, Alejandro Velasco-Castrillón e William F. Humphreys. "Multiple molecular markers reinforce the systematic framework of unique Australian cave fishes (Milyeringa : Gobioidei)". Australian Journal of Zoology 66, n. 2 (2018): 115. http://dx.doi.org/10.1071/zo18008.
Testo completoAbstract (sommario):
Australia was once thought to be a biodiversity desert when considering the subterranean world; however, recent work has revealed a fascinating collection of cave creatures, many with surprising biogeographic histories. This has especially been so in the karstic regions of north-western Australia (Cape Range peninsula, Barrow Island, Pilbara), which is home not only to a diverse collection of subterranean invertebrates, but also to the continent’s only known underworld-adapted vertebrates, which includes the cave fish in the genus Milyeringa. These cave gudgeons have recently been in a state of taxonomic flux, with species being both split and lumped, but this was done with limited data (incomplete geographic sampling and no nuclear DNA sequence data). Therefore, we have revisited the systematic status of Milyeringa in a total-evidence molecular approach by integrating all existing data (mitochondrial, allozymes) with new DNA sequences from nuclear and mitochondrial loci and new multilocus allozyme data. Our conclusion, that there are two species, matches the most recent taxonomic treatment, with Milyeringa veritas present on both the eastern and western sides of the Cape Range peninsula, and Milyeringa justitia on Barrow Island. This has implications for future research in the linked fields of biogeography and conservation.
13
Zamorano, Daniel, Fabio A. Labra, Marcelo Villarroel, Shaw Lacy, Luca Mao, Marcelo A. Olivares e Matías Peredo-Parada. "Assessing the effect of fish size on species distribution model performance in southern Chilean rivers". PeerJ 7 (6 dicembre 2019): e7771. http://dx.doi.org/10.7717/peerj.7771.
Testo completoAbstract (sommario):
Despite its theoretical relationship, the effect of body size on the performance of species distribution models (SDM) has only been assessed in a few studies, and to date, the evidence shows unclear results. In this context, Chilean fishes provide an ideal case to evaluate this relationship due to their short size (fishes between 5 cm and 40 cm) and conservation status, providing evidence for species at the lower end of the worldwide fish size distribution and representing a relevant management tool for species conservation. We assessed the effect of body size on the performance of SDM in nine Chilean river fishes, considering the number of records, performance metrics, and predictor importance. The study was developed in the Bueno and Valdivia basins of southern Chile. We used a neural network modeling algorithm, training models with a cross-validation scheme. The effect of fish size on selected metrics was assessed using linear models and beta regressions. While no relationship between fish size and the number of presences was found, our results indicate that the model specificity increases with fish size. Additionally, the predictive importance of Riparian Vegetation and Within-Channel Structures variables decreases for larger species. Our results suggest that the relationship between the grain of the dataset and the home range of the species could bias SDM, leading in our case, to overprediction of absences. We also suggest that evolutionary adaptation to low slopes among Chilean fishes increases the relevance of riparian vegetation in the SDMs of smaller species. This study provides evidence on how species size may bias SDM, which could potentially be corrected by adjusting the model grain.
14
Nelson, Jay A., Portia S. Gotwalt e Joel W. Snodgrass. "Swimming performance of blacknose dace (Rhinichthys atratulus) mirrors home-stream current velocity". Canadian Journal of Fisheries and Aquatic Sciences 60, n. 3 (1 marzo 2003): 301–8. http://dx.doi.org/10.1139/f03-023.
Testo completoAbstract (sommario):
Flowing waters may represent a force that structures the locomotor capacity of stream fishes. We used a modified critical swimming speed (Ucrit) procedure to investigate the relationship between base-flow conditions and locomotor performance of blacknose dace (Rhinichthys atratulus) from five sites within three watersheds of Baltimore County, Maryland. Our modified test used 5-min intervals between incremental increases of 5 cm·s1 in swim-tunnel current velocity. This time increment represented a realistic transit time across riffles found in the home streams of dace. To characterize current velocity conditions of the streams, we measured current velocity at 55 evenly spaced points per site during base-flow conditions. Swimming performance varied greatly among 32 individual fish from the five sites (55Ucrit from 26.33 to 69.00 cm·s1) and was positively correlated (r2 = 0.38, p = 0.002) with mean base-flow current velocities at the site of collection. Additionally, among fish from the site with the widest and most even distribution of current velocities (from 0 to 54 cm·s1), we observed the largest range of swimming performances. Our results suggest that variation in flow conditions among streams influences swimming ability of blacknose dace and can result in heretofore-unappreciated intraspecific variation in swimming performance.
15
Ward, A. J. W., R. James, A. D. M. Wilson e M. M. Webster. "Site fidelity and localised homing behaviour in three-spined sticklebacks (Gasterosteus aculeatus)". Behaviour 150, n. 14 (2013): 1689–708. http://dx.doi.org/10.1163/1568539x-00003115.
Testo completoAbstract (sommario):
The ability of animals to disperse towards their original home range following displacement has been demonstrated in a number of species. However, little is known about the homing ability of three-spine sticklebacks (Gasterosteus aculeatus), an important model species in behavioural ecology. In addition, few studies have examined the role of social facilitation in relation to homing behaviour in fishes. We examined homing behaviour of sticklebacks displaced over distances of between 80 m and 160 m in land-drains with directional water flow. Fish were translocated from their original capture site, tagged and then released either in groups or solitarily. We performed recapture transects either one or two days later. Data provided by recaptured sticklebacks show that the fish dispersed in the direction of their original capture site. Although fish translocated downstream typically moved further than those translocated upstream, both dispersed towards their original capture site. There was no difference between fish released solitarily or in groups in their homing ability and indeed there was little evidence that fish translocated in groups remained together following their release. The homing ability of the fish was demonstrated by the finding that up to 80% of fish returned to their home ranges within two days of release over a distance equivalent to approximately 5000 body lengths of these small fish.
16
Taborsky, Barbara. "Mothers determine offspring size in response to own juvenile growth conditions". Biology Letters 2, n. 2 (5 gennaio 2006): 225–28. http://dx.doi.org/10.1098/rsbl.2005.0422.
Testo completoAbstract (sommario):
Through non-genetic maternal effects, mothers can tailor offspring phenotype to the environment in which young will grow up. If juvenile and adult ecologies differ, the conditions mothers experienced as juveniles may better predict their offspring's environment than the adult environment of mothers. In this case maternal decisions about investment in offspring quality should already be determined during the juvenile phase of mothers. I tested this hypothesis by manipulating juvenile and adult maternal environments independently in a cichlid fish. Females raised in a poor environment produced larger young than females raised without food limitations, irrespective of the feeding conditions experienced during adulthood. This maternal boost was due to a higher investment in eggs and to faster larval growth. Apparently, mothers prepare their offspring for similar environmental conditions to those they encountered as juveniles. This explanation is supported by the distribution of these fishes under natural conditions. Juveniles live in a different and much narrower range of habitats than adults. Therefore, the habitat mothers experienced as juveniles will allow them to predict their offspring's environment better than the conditions in the adult home range.
17
Paglianti, Annalisa, Giuseppe Messana, Alessandro Cianfanelli e Roberto Berti. "Is the perception of their own odour effective in orienting the exploratory activity of cave fishes?" Canadian Journal of Zoology 84, n. 6 (giugno 2006): 871–76. http://dx.doi.org/10.1139/z06-072.
Testo completoAbstract (sommario):
Spatial knowledge of the surrounding environment is extremely important for animals to locate and efficiently exploit available resources (e.g., food, shelters, mates). Fishes usually acquire spatial information about their home range through vision, but vision fails in the dark and other sensory pathways have to be exploited. Fishes possess a remarkable olfactory system and have evolved a refined ability of chemical detection and recognition. Nevertheless, while the role of chemical cues in spatial orientation is well known in long-distance salmonid migrations, it has never been investigated in orientation within local, familiar areas. Here we report the first evidence that fish swimming can be topographically polarized by self-odour perception. When an unfamiliar area was experimentally scented with fish self-odour, the cave cyprinid Phreatichthys andruzzii Vinciguerra, 1924 behaved as if the area was previously explored. The fish preferred an odour-free area to a self-odour-scented one, and when offered the choice between a familiar and an unfamiliar area, they preferred the unexplored environment. Avoidance of self-odour-scented areas would allow effective exploration of the subterranean environment, minimizing the risks of repeatedly exploring the same water volumes. Our results are the first clear evidence that fish can use their own odour to orient their locomotor activity when visual cues are not available. This highlights the possible role of chemical information in fish orientation.
18
Kordosky, Jennifer R., Eric M. Gese, Craig M. Thompson, Patricia A. Terletzky, Kathryn L. Purcell e Jon D. Schneiderman. "Landscape use by fishers (Pekania pennanti): core areas differ in habitat than the entire home range". Canadian Journal of Zoology 99, n. 4 (aprile 2021): 289–97. http://dx.doi.org/10.1139/cjz-2020-0073.
Testo completoAbstract (sommario):
Home ranges have long been studied in animal ecology. Core areas may be used at a greater proportion than the rest of the home range, implying the core contains dependable resources. The Pacific fisher (Pekania pennanti (Erxleben, 1777)) is a rare mesocarnivore occupying a small area in the Sierra Nevada Mountains, California, USA. Once statewide, fishers declined in the 1900s due to trapping, habitat fragmentation, and development. Recently, drought induced by climate change may be affecting this population. We examined space use of fishers in their core versus their home range for levels of anthropogenic modifications (housing density, road density, silvicultural treatments), habitat types, and tree mortality. We found core areas contained more late-successional forest and minimal human activity compared with their territory. Their core had higher levels of dense canopy and higher amounts of conifer cover, while minimizing the amount of buildings, developed habitat, and low canopy cover. Fishers may in effect be seeking refugia by minimizing their exposure to these elements in their core. Conserving landscape components used by fishers in their core areas will be important for the persistence of this isolated population.
19
Kordosky, Jennifer R., Eric M. Gese, Craig M. Thompson, Patricia A. Terletzky, Lorin A. Neuman-Lee, Jon D. Schneiderman, Kathryn L. Purcell e Susannah S. French. "Landscape of stress: Tree mortality influences physiological stress and survival in a native mesocarnivore". PLOS ONE 16, n. 7 (1 luglio 2021): e0253604. http://dx.doi.org/10.1371/journal.pone.0253604.
Testo completoAbstract (sommario):
Climate change and anthropogenic modifications to the landscape can have both positive and negative effects on an animal. Linking landscape change to physiological stress and fitness of an animal is a fundamental tenet to be examined in applied ecology. Cortisol is a glucocorticoid hormone that can be used to indicate an animal’s physiological stress response. In the Sierra Nevada Mountains of California, fishers (Pekania pennanti) are a threatened mesocarnivore that have been subjected to rapid landscape changes due to anthropogenic modifications and tree mortality related to a 4-year drought. We measured cortisol concentrations in the hair of 64 fishers (41 females, 23 males) captured and radio-collared in the Sierra National Forest, California. We addressed two main questions: (1) Is the physiological stress response of fishers influenced by anthropogenic factors, habitat type, canopy cover, and tree mortality due to drought in their home range? (2) Does the physiological stress response influence survival, reproduction, or body condition? We examined these factors within a fisher home range at 3 scales (30, 60, 95% isopleths). Using model selection, we found that tree mortality was the principle driver influencing stress levels among individual fishers with female and male fishers having increasing cortisol levels in home ranges with increasing tree mortality. Most importantly, we also found a link between physiological stress and demography where female fishers with low cortisol levels had the highest annual survival rate (0.94), whereas females with medium and high cortisol had lower annual survival rates, 0.78 and 0.81, respectively. We found no significant relationships between cortisol levels and body condition, male survival, or litter size. We concluded that tree mortality related to a 4-year drought has created a “landscape of stress” for this small, isolated fisher population.
20
Farmer, Nicholas A., e Jerald S. Ault. "Accounting for detection gaps when evaluating reef fish habitat use in an acoustic array". Canadian Journal of Fisheries and Aquatic Sciences 75, n. 3 (marzo 2018): 375–88. http://dx.doi.org/10.1139/cjfas-2016-0494.
Testo completoAbstract (sommario):
Understanding the relationship between habitats and the distribution of fishes is critical to effective survey design and spatial management. Determining reef fish habitat utilization patterns from passive acoustic arrays is challenging for the following reasons: (i) habitat classifications must be meaningful to the species, (ii) the array must contain the species’ home range, and (iii) the probability of detection may differ among habitats within the array. We conducted a multi-year tracking study in the marine protected areas (MPAs) of Dry Tortugas, Florida, using a calibrated passive acoustic array deployed over habitats classified by type (reef, rubble, sand), rugosity (high, medium, low relief), and patchiness (contiguous, spur-and-groove, isolated). Our design controlled for differences between individuals, diel and edge effects, and detection gaps resulting from the nonlinear relationship between acoustic tag detection probabilities as a function of distance from the receiver. We found red and black groupers preferred high-relief reef habitats, whereas mutton and yellowtail snappers preferred low-relief contiguous reef habitats. By identifying critical habitats for exploited species, our analysis may facilitate more efficient fishery-independent sampling and MPA designs.
21
Nakano, Shigeru. "Competitive interactions for foraging microhabitats in a size-structured interspecific dominance hierarchy of two sympatric stream salmonids in a natural habitat". Canadian Journal of Zoology 73, n. 10 (1 ottobre 1995): 1845–54. http://dx.doi.org/10.1139/z95-217.
Testo completoAbstract (sommario):
Aggressive interactions, foraging behaviour, microhabitats, and growth of individuals of two sympatric stream-dwelling salmonids, white-spotted charr (Salvelinus leucomaenis) and masu salmon (Oncorhynchus masou masou), were studied in a mountain stream in central Japan. The fishes within a single pool in the stream formed an interspecific size-structured dominance hierarchy. Dominant individuals of both species maintained foraging territories against both subordinate conspecifics and heterospecifics, whereas subordinate charr adopted nonterritorial tactics. In each species, the most dominant fish usually held the focal point nearest to the pool inlet, which ensured priority of access to drifting food, with subordinates distributed farther downstream. Foraging microhabitats differed vertically in the water column between the two species, charr utilizing a home range near the stream bed and salmon occupying the midlayer. The frequency of foraging attempts by salmon was considerably higher than that by charr. Although daily body mass increments of dominant individuals were significantly larger than those of conspecific subordinates in each species, those of some subordinate salmon exceeded those of dominant charr.
22
Colombano, DD, AD Manfree, TA O’Rear, JR Durand e PB Moyle. "Estuarine-terrestrial habitat gradients enhance nursery function for resident and transient fishes in the San Francisco Estuary". Marine Ecology Progress Series 637 (5 marzo 2020): 141–57. http://dx.doi.org/10.3354/meps13238.
Testo completoAbstract (sommario):
Nursery functions of US West Coast drowned river valley estuaries are not well understood. Using long-term fish-monitoring data (1995-2017) in Suisun Marsh, San Francisco Estuary, California, USA, we examined spatial and temporal trends in abundance and apparent growth of fishes with diverse life-history types. Focal species were Sacramento splittail Pogonichthys macrolepidotus, striped bass Morone saxatilis, tule perch Hysterocarpus traski, and starry flounder Platichthys stellatus, which collectively represented 55% of total catch (n = 140092). We identified keystone habitat patches that functioned as nursery hotspots during the peak young-of-the-year recruitment window. Deep, flow-through sloughs close to the open estuary were important nursery habitats for the marine transient starry flounder. In contrast, splittail and striped bass mostly migrated through such corridors to rear in shallow, dead-end sloughs bisecting tidal marsh plains, managed tidal ponds, and uplands. Tule perch were concentrated in shallow, interior sloughs, reflecting their resident life-history type and adaptations to variable conditions in a small home range. Interactions among freshwater flows and stationary habitat features (e.g. channel depth, land-to-open-water ratio) were related to fish abundance; however, species and age classes differed in their relationships to these interactions, suggesting a mechanism for habitat partitioning in space and time. Overall, we inferred that habitat connectivity—longitudinal, lateral, and vertical—along the estuarine-terrestrial gradient was a driver of fish species diversity and productivity. Consideration of seascape-landscape dynamics across multiple spatial and temporal scales in estuaries should help maintain or increase fish populations and ecological resilience in the face of rising sea levels and other environmental stressors.
23
Arthur, Stephen M., William B. Krohn e James R. Gilbert. "Home Range Characteristics of Adult Fishers". Journal of Wildlife Management 53, n. 3 (luglio 1989): 674. http://dx.doi.org/10.2307/3809196.
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Gray, Michelle A., R. Allen Curry, Tim J. Arciszewski, Kelly R. Munkittrick e Sandra M. Brasfield. "The biology and ecology of slimy sculpin: A recipe for effective environmental monitoring". FACETS 3, n. 1 (1 ottobre 2018): 103–27. http://dx.doi.org/10.1139/facets-2017-0069.
Testo completoAbstract (sommario):
Recently, the use of small-bodied fish in environmental monitoring has increased, particularly within the Canadian environmental effects monitoring (EEM) and other adaptive programs. Although it is possible to measure changes with many small-bodied species, interpretation is often complicated by the absence of information on the biology and ecology of fish not of commercial, recreational, or traditional interest. Knowing and understanding the basic biology of these fishes aids in the sensitivity of study designs (i.e., ability to detect change) and the interpretation of all biological levels of responses (e.g., cellular to community). The increased use of slimy sculpin ( Cottus cognatus Richardson, 1836) in impact assessment studies in North America provides a considerable amount of information on life history aspects. The slimy sculpin has the most ubiquitous North American distribution among cottids but yet has a very small home range, thus integrating environmental conditions of localized areas. This paper describes aspects of slimy sculpin life cycle that affect collection efficiency and timing, and describes and provides data collected over more than 10 years of studies at more than 20 reference study sites. This overview provides a functional and informative compilation to support adaptive environmental monitoring and provide a baseline for comparative ecological study.
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KOEN, ERIN L., JEFF BOWMAN, C. SCOTT FINDLAY e LIGANG ZHENG. "Home Range and Population Density of Fishers in Eastern Ontario". Journal of Wildlife Management 71, n. 5 (luglio 2007): 1484–93. http://dx.doi.org/10.2193/2006-133.
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Léopold, Marc, Nicolas Guillemot, Delphine Rocklin e Cheryl Chen. "A framework for mapping small-scale coastal fisheries using fishers' knowledge". ICES Journal of Marine Science 71, n. 7 (11 gennaio 2014): 1781–92. http://dx.doi.org/10.1093/icesjms/fst204.
Testo completoAbstract (sommario):
Abstract Collecting spatial information on fisheries catch and effort is essential to understanding the spatial processes of exploited population dynamics and to manage heterogeneously distributed resources and uses. The use of fishers' knowledge through geographical information systems (GISs) is increasingly considered as a promising source of local information on small-scale coastal fisheries. In this paper we describe the first framework for mapping entire small-scale coastal fisheries using fishers' knowledge on catch size and fishing effort. Four mangrove and coral reef fisheries targeting invertebrates or finfish in New Caledonia (southwest Pacific) were mapped following a five-step framework: (i) stratified random sampling of regular fishers; (ii) collection of fishers' knowledge of fishing areas, fishing effort, and catch size through map-based interviews; (iii) data integration into a spatial geodatabase; (iv) statistical extrapolation of fisher data to the fishery scale; and (v) mapping of catch, effort, and catch per unit effort (CPUE) for each fishery using a GIS overlay procedure. We found evidence that fishers' knowledge supplied precise and accurate quantitative and spatial information on catch size, fishing effort and CPUE for entire fisheries. Fisheries maps captured the fine-scale spatial distribution of fishing activities in a variety of ways according to target taxa, gear type, and home ports. Applications include area-based marine conservation planning and fishery monitoring, management, and governance. This integrated framework can be generalized to a large range of data-poor coastal and inland small-scale fisheries.
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SHEPHERD, S. A., P. MARTINEZ, M. V. TORAL-GRANDA e G. J. EDGAR. "The Galápagos sea cucumber fishery: management improves as stocks decline". Environmental Conservation 31, n. 2 (giugno 2004): 102–10. http://dx.doi.org/10.1017/s0376892903001188.
Testo completoAbstract (sommario):
The Galápagos Islands, a world heritage region for the protection of the unique terrestrial and marine wildlife, are also home to a small human population, dependent on fisheries. There was a lucrative sea-cucumber (Stichopus fuscus) fishery in the islands, which began in 1992. After a rapid expansion in the Galápagos archipelago, the fishery has declined and now persists predominantly around the western islands. Initially, the fishery was largely illegal and uncontrollable. Subsequently, a co-management framework developed, with fisher participation. Gradually enforcement improved, apparent corruption declined, and research capacity increased. Although stock abundance surveys have been carried out annually since 1993, the paucity of background biological and fishery information does not allow rigorous stock assessment. The achievements of co-management through the participation of fishers in research and management have been: an acceptance of management controls on numbers of fishers and quotas, a reduction in conflict and increased co-operation. Persistent problems have been: weak enforcement capacity, limited funds for patrolling and research, corruption and declining stock abundance. Proposed application of precautionary principles to management, including a range of fishery indicators, may save the fishery from collapse. The principles are applicable to many other data-poor fisheries globally.
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Vokoun, Jason C. "Kernel Density Estimates of Linear Home Ranges for Stream Fishes: Advantages and Data Requirements". North American Journal of Fisheries Management 23, n. 3 (agosto 2003): 1020–29. http://dx.doi.org/10.1577/m02-141.
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Sauder, Joel D., e Janet L. Rachlow. "Forest heterogeneity influences habitat selection by fishers (Pekania pennanti) within home ranges". Forest Ecology and Management 347 (luglio 2015): 49–56. http://dx.doi.org/10.1016/j.foreco.2015.03.009.
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Davis, Frank W., Changwan Seo e William J. Zielinski. "REGIONAL VARIATION IN HOME-RANGE-SCALE HABITAT MODELS FOR FISHER (MARTES PENNANTI) IN CALIFORNIA". Ecological Applications 17, n. 8 (dicembre 2007): 2195–213. http://dx.doi.org/10.1890/06-1484.1.
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Saul, Steven, Elizabeth N. Brooks e David Die. "How fisher behavior can bias stock assessment: insights from an agent-based modeling approach". Canadian Journal of Fisheries and Aquatic Sciences 77, n. 11 (novembre 2020): 1794–809. http://dx.doi.org/10.1139/cjfas-2019-0025.
Testo completoAbstract (sommario):
During stock assessment, fishery-dependent observations are often used to develop indices of abundance or biomass from catch per unit of effort (CPUE) and contribute catch at size or age information. However, fisher behavior, rather than scientific sampling protocols, determines the spatial and temporal locations of fishery-dependent observations. As a result, trends from fishery-dependent data may be a function of fishing activity rather than fish population changes. This study evaluates whether data collected from commercial fishing fleets in the Gulf of Mexico are representative of trends in fish population size. A coupled bioeconomic agent-based model was developed to generate simulated fishery data, which were used to populate an age-structured stock assessment. Comparison of stock assessment results with simulated fish population dynamics showed that management advice from assessment models based on fishery-dependent data could be biased. Assessment of fish with small home ranges harvested by fishing fleets that frequent the same fishing grounds could cause overestimation of fishing mortality. Not accounting for the spatial structure of the fishers or fish can cause biased estimates of population status.
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Eddy, Tyler D., Alan M. Friedlander e Pelayo Salinas de León. "Ecosystem effects of fishing & El Niño at the Galápagos Marine Reserve". PeerJ 7 (8 maggio 2019): e6878. http://dx.doi.org/10.7717/peerj.6878.
Testo completoAbstract (sommario):
The Galápagos Archipelago is home to a diverse range of marine bioregions due to the confluence of several cold and warm water currents, resulting in some of the most productive tropical marine ecosystems in the world. These ecosystems are strongly influenced by El Niño events which can reduce primary production by an order of magnitude, dramatically reducing energy available throughout the food web. Fisheries are an important component of the local economy, although artisanal and illegal overfishing have dramatically reduced the productivity of invertebrate and finfish resources in recent decades, resulting in reductions in catches for local fishers. The regionally-endemic sailfin grouper (Myctereoperca olfax), locally known as bacalao, was once the most important fished species in the Galápagos, but is now listed as vulnerable by the IUCN due to its limited range and dramatic declines in catch over time. It is unknown how reduction of this predatory species has affected ecosystem structure and function. In the absence of stock assessments, we used an estimate of unfished bacalao biomass from fishers’ ecological knowledge along with unfished biomass estimates of other heavily exploited stocks—lobster (Panulirus penicillatus and P. gracilis) and sea cucumber (Isostichopus fuscus)—to create historical, unfished versions of existing modern day ecosystem models. We used the unfished and modern versions of the ecosystem models to test the ecosystem effects of bacalao exploitation at the Bolivar Channel, located in the cold, west upwelling bioregion of the archipelago during both El Niño and non El Niño years, and at Floreana Island, in the warmer, central bioregion. Fishers’ ecological knowledge indicates that at present, the biomass of bacalao is at least seven times lower than when unfished. This reduced bacalao biomass is linked with a greatly reduced ecosystem role compared to when unfished, and ecosystem role is further reduced in El Niño years. Allowing bacalao populations to rebuild to at least half of unfished biomass would partially restore their role within these ecosystems, while also resulting in greater fisheries catches. Comparing ecosystem impacts caused by fishing and El Niño, fishing has had a greater negative impact on bacalao ecosystem role than regular El Niño events.
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Furnas, B. J., R. H. Landers, R. L. Callas e S. M. Matthews. "Estimating population size of fishers (Pekania pennanti ) using camera stations and auxiliary data on home range size". Ecosphere 8, n. 3 (marzo 2017): e01747. http://dx.doi.org/10.1002/ecs2.1747.
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Wiig, Jørgen Ree, Even Moland, Thrond O. Haugen e Esben Moland Olsen. "Spatially structured interactions between lobsters and lobster fishers in a coastal habitat: fine-scale behaviour and survival estimated from acoustic telemetry". Canadian Journal of Fisheries and Aquatic Sciences 70, n. 10 (ottobre 2013): 1468–76. http://dx.doi.org/10.1139/cjfas-2013-0209.
Testo completoAbstract (sommario):
Fishing can have profound impacts on the ecology and evolution of marine populations. Understanding population-level changes ultimately depends on knowledge about individual survival and how it varies in time and space. We used acoustic tags and a network of receivers to monitor individual behaviour and fate of European lobster (Homarus gammarus) exposed to commercial and recreational trap fisheries on the Norwegian Skagerrak coast. In August 2011, 50 male lobsters above minimum legal size were tagged and monitored before and during the lobster fishing season. We also quantified the spatial and temporal variation in fishing activity. There was no significant effect of home-range size on the probability of surviving the fishery. However, there was substantial fine-scale spatial variation in fishing activity, and lobsters with short-term home ranges positioned away from trap-dense areas had a significantly higher survival probability. Also, the overall survival probability of 16.7% suggests that fishing depletes the catchable lobster population at a high rate. The current harvesting regime may drive selection in favour of movement behaviours avoiding habitats typically targeted by fishers.
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Crossman, E. J. "Reproductive Homing in Muskellunge, Esox masquinongy". Canadian Journal of Fisheries and Aquatic Sciences 47, n. 9 (1 settembre 1990): 1803–12. http://dx.doi.org/10.1139/f90-205.
Testo completoAbstract (sommario):
The number and nature of muskellunge moving to and from spawning grounds are extensively documented. Individual spawning muskeliunge in Stony Lake, Ontario are considered to home annually to specific spawning grounds and to specific areas (spawning sites) within spawning grounds. Some individuals were caught in the same location, or a nearby location, in as many as 7 yr. There is some evidence for discrete populations with apparent reproductive isolation and no interchange in summer. Dispersal from spawning grounds to summer home ranges seems to be limited in regard to direction and area of the lake. Recapture of fish on spawning grounds suggests an obligatory return to a limited number of "traditional" spawning grounds and may extend our knowledge of the groups of fishes exhibiting this type of directed movement. The results also have serious implications for muskellunge in regard to management, shoreline development, and genetic contamination by fish culture activities.
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Soar, N., J. Birns, P. Sommerville, A. Lang, A. Fitzgerald e S. Archer. "136 Readmissions to Hospital Following A Decision to Eat and Drink with Acknowledged Risk with Support From the Forward Care Bundle". Age and Ageing 50, Supplement_1 (marzo 2021): i12—i42. http://dx.doi.org/10.1093/ageing/afab030.97.
Testo completoAbstract (sommario):
Abstract Introduction The FORWARD care bundle (Feeding via the Oral Route With Acknowledged Risk of Deterioration) is used to support patients with dysphagia eating and drinking with acknowledged risk (EDAR) at our Trust. Key aims of FORWARD include improving advanced care planning (ACP) and avoiding unnecessary readmissions. This study aimed to determine the incidence of EDAR related readmissions (RR-EDAR) after FORWARD, and the effects of ACP and discharge location. Methods Retrospective review of all patients supported by FORWARD during admissions between January 2018 and December 2019. Data were collected on number and reasons for in-Trust hospital readmissions 6 months post-discharge, preferred place of care ACPs in event of EDAR related deterioration and discharge destination. Readmission reasons were classified as RR-EDAR (e.g. chest infection, reduced oral intake) and no relation to EDAR. Means (SD) and percentages are presented with comparisons using Fishers Exact Test. Results 316 patients were included; mean (SD) age 81(12). 64% (n = 202) of patients were discharged alive, 36% (n = 114) were alive at 6 months. 38% of live discharges (n = 75) were readmitted and 52% (n = 39) of these patients were RR-EDAR. Mean (SD) RR-EDAR number was 11, and 18% (n = 7) of patients had RR-EDAR >1 (range 1–5). RR-EDAR was only 7% (n = 4) in patients wishing to remain at home vs 25% (n = 33) in those without a documented place of care (p < 0.01). RR-EDAR was 23% (n = 29) in patients discharged to a private home vs 10% (n = 6) discharged to nursing/care homes (p < 0.05). Conclusions The majority of FORWARD patients are not readmitted. RR-EDAR comprises half of all readmitted patients and some have multiple admissions. Fewer patients with ACPs were RR-EDAR suggesting these are effective. Most patients RR-EDAR were from private homes, suggesting residential care may provide more support. Further work includes increasing ACPs, supporting patients with multiple RR-EDAR and those discharged to private homes.
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Yan, Lang, Xinghua Chang, Runyu Tian, Nianhua Wang, Laiping Zhang e Wei Liu. "A numerical simulation method for bionic fish self-propelled swimming under control based on deep reinforcement learning". Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 234, n. 17 (26 marzo 2020): 3397–415. http://dx.doi.org/10.1177/0954406220915216.
Testo completoAbstract (sommario):
In order to simulate the under control self-propelled swimming of bionic fishes, a coupling method of hydrodynamics/kinematics/motion-control is presented in this paper. The Navier-Stokes equations in the arbitrary Lagrangian-Eulerian framework are solved in parallel based on the computational domain decomposition to simulate the unsteady flow field efficiently. The flow dynamics is coupled with the fish dynamics in an implicit way by a dual-time stepping approach. In order to discretize the computational domain during a wide range maneuver, an overset grid approach with a parallel implicit hole-cutting technique is adopted and coupled with morphing hybrid grids around the undulation body. The motion control of the fish swimming is realized by a deep reinforcement learning algorithm, which makes the fish model choose proper undulation manner according to a specific purpose. By adding random disturbances in the training process of fish swimming along a straight line, a simplified two-dimensional fish model obtains the ability to swim along a specific trajectory. Then in subsequent tests, the two-dimensional fish model is able to swim along more complex curves with obstacles. Finally, the starting process of a three-dimensional tuna-like model is simulated preliminarily to validate the ability of the coupling method for three-dimensional complex configurations. The numerical results demonstrate that this study could be used to explore the swimming mechanism of fishes in complex environments and to guide how robotic fishes can be controlled to accomplish their tasks.
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Buyle, Pieter, Maarten Baes e Herwig Dejonghe. "Tracing the relation between black holes and dark haloes". Symposium - International Astronomical Union 220 (2004): 317–18. http://dx.doi.org/10.1017/s0074180900183494.
Testo completoAbstract (sommario):
We present new velocity dispersion measurements for a set of 12 spiral galaxies and use them to derive a more accurate υc – σ relation which holds for a wide morphological range of galaxies. Combined with the MBH – σ relation, this relation can be used as a tool to estimate supermassive black hole (SMBH) masses by means of the asymptotic circular velocity. Together with the Tully-Fisher relation, it serves as a constraint for galaxy formation and evolution models.
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Chateau, Olivier, e Laurent Wantiez. "Movement patterns of four coral reef fish species in a fragmented habitat in New Caledonia: implications for the design of marine protected area networks". ICES Journal of Marine Science 66, n. 1 (9 ottobre 2008): 50–55. http://dx.doi.org/10.1093/icesjms/fsn165.
Testo completoAbstract (sommario):
Abstract Chateau, O., and Wantiez, L. 2009. Movement patterns of four coral reef fish species in a fragmented habitat in New Caledonia: implications for the design of marine protected area networks. – ICES Journal of Marine Science, 66: 50–55. Acoustic telemetry was used to examine the patterns of fish movements between a marine reserve and two unprotected reefs separated by large areas of lagoon soft bottoms (900–2000 m) in the South Lagoon Marine Park of New Caledonia. Four commercial fish species (Epinephelus maculatus, Plectropomus leopardus, Chlorurus microrhinos, and Scarus ghobban) were studied for 17 months (45 fish). Nine fish (20%) were detected on reefs other than the reef onto which they were released. Four patterns of inter-reef movement were identified during the survey, including home range relocations, movements larger than the scale of the study, many inter-reef movements within the study area, and punctual excursions outside the daily home range. The information gathered in this study demonstrates the ability of the fish to carry out medium-scale movements in a fragmented habitat. Consequently, the effectiveness of the reserve to protect the entire population is probably limited for these species. Because all the identified patterns implied at least one movement across the reserve boundaries, our results support the hypothesis that the Larégnère Marine Reserve, part of the South Lagoon Marine Park, could benefit the adjacent fished area through spillover.
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Ebner, B. C., L. Johnston e M. Lintermans. "Radio-tagging and tracking of translocated trout cod (Maccullochella macquariensis: Percichthyidae) in an upland river". Marine and Freshwater Research 60, n. 4 (2009): 346. http://dx.doi.org/10.1071/mf08257.
Testo completoAbstract (sommario):
Radio-tracking provides an effective means of studying the spatial ecology of threatened fishes where almost inaccessible habitats and species rarity render conventional mark–recapture methods impractical. Initially, validation of an effective radio-tagging method is required; in the present study, an aquaria trial based on nine hatchery-reared, adult male Maccullochella maquariensis (Percichthyidae) was conducted. Fish resumed feeding within days of being internally implanted with a radio-tag, and tag rejection was not observed (0%, n = 9) based on a 2-month observational period. Following release into an upland stream, individual-specific movements resulted in upstream (n = 1) and downstream (n = 6) dispersal as well as fidelity to the release site (n = 2) at the completion of the study. Individuals established small home-ranges (mean length of river used by an individual per diel period ranged from 47 to 292 m) and were most active in the early morning and evening (n = 6). Complete survivorship of individuals bearing active radio-transmitters (n = 8) was recorded up until 4 months after release. However, an estimated zero or one individual was alive when the last active radio-tag expired 11 months after release (n = 8). The present study highlights the use of radio-tracking in monitoring the dispersal and survivorship of small numbers of hatchery-reared threatened fish released into natural habitats as part of species re-introduction programs.
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Hindmarch, Sofi, e John E. Elliott. "Comparing the diet of Great Horned Owls (Bubo virginianus) in rural and urban areas of southwestern British Columbia". Canadian Field-Naturalist 128, n. 4 (4 febbraio 2015): 393. http://dx.doi.org/10.22621/cfn.v128i4.1634.
Testo completoAbstract (sommario):
We investigated the diet of Great Horned Owls (Bubo virginianus) in southwestern British Columbia. Our objective was to compare the diets of owls in urban and rural areas and determine whether urban owls consume a higher proportion of commensal rodents to understand possible pathways of secondary rodenticide poisoning of Great Horned Owls. Among 546 prey items identified at seven sites, Townsend’s Vole (Microtus townsendii [Bachman, 1839]) and rats (Rattus G. Fischer, 1803) were the two main prey items, making up 65.9% and 13.1% of the diet, respectively. The proportion of rats in the diet was positively correlated with the degree of urban development in the owls’ home range (rp = 0.83, P < 0.05, df = 5).
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Alfaro, Maricarmen, Raquel Baldeos, Beatriz Rosales, Maria Berenguel e Alfredo Aguilar. "Pain assessment behavioral scale in agonic cancer patients: Experience in total care—An end-of-life care home service." Journal of Clinical Oncology 30, n. 15_suppl (20 maggio 2012): e19636-e19636. http://dx.doi.org/10.1200/jco.2012.30.15_suppl.e19636.
Testo completoAbstract (sommario):
e19636 Background: Assessing pain in nonverbal, especially agonic cancer patients is a great challenge. In the absence of self-report, measurement of pain could be difficult and patient`s behavior could be useful. The aim of this work was to evaluate the Pain Assessment Behavioral Scale (PABS) in cancer agonic patients. Methods: PABS scale was used to evaluate 118 cancer patients enter in agony. Pain levels was categorized according to PABS score in Mild Pain (score 1-3), Moderate Pain (score 4-5), Severe Pain (score>6). We correlated levels of pain with age, sex, cancer metastatic site or active tumor localization with the ANOVA, Chi square or Fisher tests when were appropriated. A P<0.05 was considered significant. Results: Fifty two patients (44.1%) were male and 66 female (55.9%). The median age was 74 (Standar Deviation [SD]:13.1; Range: 30-94). Most frequent primary tumors were colorectal (16%), lung (11%), Pancreas (9.3%), Breast (8.5%), lymphomas (6.8%), prostate (6.8%) and gastric (5.6%) cancer. Involvement of primary active tumor or active metastases was present in lung (22%), Central Nervous System (CNS) (13.6%), liver (22%), and bone (7.6%). The median of PABS score was 5 (SD=1.25; range: 2 – 8). Seven cases had mild pain (5.9%), 105 moderate pain (89%) and 6 severe pain (5.1%). There was no correlation of pain levels with age (P=0.420), sex (P=0.098), active tumor or metastatic involvement of lung (P=0.321), CNS (P=0.972), Liver (P=0.575) or bone (P=0.529). Conclusions: In our experience, PABS scale is a useful tool to evaluate pain in agony cancer patients. We found no correlation between active tumor or metastatic localization with the intensity of pain.
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Matthews, G. V. T. "Navigation in Animals". Journal of Navigation 50, n. 3 (settembre 1997): 448–57. http://dx.doi.org/10.1017/s037346330001907x.
Testo completoAbstract (sommario):
This paper was first published in the Journal in 1969 (Vol. 22, p. 118). It is followed by comments from John Kemp.The last twenty-one years have seen some very striking advances in our knowledge of how animals can determine their location. In many cases we have learned that they have available a wider range of stimuli than ourselves for recognizing landmarks and for pilotage within their home area. Thus the associated senses of smell and taste are extraordinarily well developed in some species. The ability of the males of certain moths to detect the scent emitted by females at very considerable distances had long been known. More recently the extreme sensitivity, and selectivity, of fish to waterborne odours has led to an understanding of how they locate their home waters. As but one example, eels have shown reactions to concentrations of chemicals as low as 3 × 10−18, equivalent to but two or three molecules within the fish's olfactory sac. In other cases animals have developed sensitivities of which we have little or no conception. Ecolocation is employed by certain birds, by many marine animals and reaches a peak of efficiency in the case of bats. Not only do the latter detect sounds of much higher frequency than ourselves, they also respond to echoes of sounds they emitted but 0·001 seconds earlier. We have little appreciation of the sensations produced by the pressure-receptors in the lateral-line organs of fish.
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Wengert, Greta M., J. Mark Higley, Mourad W. Gabriel, Heather Rustigian-Romsos, Wayne D. Spencer, Deana L. Clifford e Craig Thompson. "Distribution of trespass cannabis cultivation and its risk to sensitive forest predators in California and Southern Oregon". PLOS ONE 16, n. 9 (1 settembre 2021): e0256273. http://dx.doi.org/10.1371/journal.pone.0256273.
Testo completoAbstract (sommario):
Illegal cannabis cultivation on public lands has emerged as a major threat to wildlife in California and southern Oregon due to the rampant use of pesticides, habitat destruction, and water diversions associated with trespass grow sites. The spatial distribution of cultivation sites, and the factors influencing where they are placed, remain largely unknown due to covert siting practices and limited surveillance funding. We obtained cannabis grow-site locality data from law enforcement agencies and used them to model the potential distribution of cultivation sites in forested regions of California and southern Oregon using maximum entropy (MaxEnt) methods. We mapped the likely distribution of trespass cannabis cultivation sites and identified environmental variables influencing where growers establish their plots to better understand the cumulative impacts of trespass cannabis cultivation on wildlife. We overlaid the resulting grow-site risk maps with habitat distribution maps for three forest species of conservation concern: Pacific fisher (Pekania pennanti), Humboldt marten (Martes caurina humboldtensis), and northern spotted owl (Strix occidentalis caurina). Results indicate that cannabis cultivation is fairly predictably distributed on public lands in low to mid-elevation (~800-1600m) forests and on moderate slopes (~30–60%). Somewhat paradoxically, results also suggest that growers either preferred sites inside of recently disturbed vegetation (especially those burned 8–12 years prior to cultivation) or well outside (>500m) of recent disturbance, perhaps indicating avoidance of open edges. We ground-truthed the model by surveying randomly selected stream courses for cultivation site presence in subsets of the modeling region and found previously undiscovered sites mostly within areas with predicted high likelihood of grow-site occurrence. Moderate to high-likelihood areas of trespass cultivation overlapped with 40 to 48% of modeled habitats of the three sensitive species. For the endangered southern Sierra Nevada fisher population, moderate-high likelihood growing areas overlapped with over 37% of modeled fisher denning habitat and with 100% of annual female fisher home ranges (mean overlap = 48.0% + 27.0 SD; n = 134) in two intensively studied populations on the Sierra National Forest. Locating and reclaiming contaminated cannabis grow sites by removing all environmental contaminants should be a high priority for resource managers.
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Kolobe, Thubi HA. "Childrearing Practices and Developmental Expectations for Mexican-American Mothers and the Developmental Status of Their Infants". Physical Therapy 84, n. 5 (1 maggio 2004): 439–53. http://dx.doi.org/10.1093/ptj/84.5.439.
Testo completoAbstract (sommario):
Abstract Background and Purpose. The impact of parent education programs on early intervention programs is not thought to be uniform among children from majority and minority populations. This study examined the relationship between maternal childrearing practices and behaviors and the developmental status of Mexican-American infants. Subjects. Participants were 62 Mexican-American mother-infant pairs. The infants' mean adjusted age was 12 months (SD=1.7, range=9–14). A third of the children were diagnosed with developmental delays and referred for early intervention by physicians or therapists when the children received their medical follow-up. The group was stratified according to socioeconomic status and acculturation using the Bidimensional Acculturation Scale for Hispanics. This scale uses cutoff points to classify individuals into 3 levels of acculturation. Methods. Information on childrearing practices and behaviors was gathered using the Parent Behavior Checklist (PBC), the Home Observation for Measurement of the Environment (HOME) Inventory, and the Nursing Child Assessment Teaching Scale (NCATS). Infants' developmental status was assessed by use of the Bayley Scales of Infant Development II (BSID II). The Pearson product moment correlation, partial correlations, Fisher z transformation, and multiple regression analyses were used to examine the relationship between childrearing practices and parenting behaviors, demographic factors, and infants' developmental status. Results. Maternal nurturing behaviors, parent-child interaction, and quality of the home environment were positively correlated with the infants' cognitive development. Maternal years of education modified the observed relationship between PBC and BSID II scores but not the observed relationship between HOME Inventory and NCATS scores. The childrearing practices, maternal socioeconomic status (SES) and age, and infants' gestational age at birth (GA) explained 45% of the variance in infants' cognitive scores. The infants' GA, maternal SES and age, and NCATS scores accounted for 32% of the motor scores on the BSID II. Discussion and Conclusion. The findings partially support a link between aspects of the mothers' childrearing behaviors and their infants' cognitive developmental status. For motor developmental status, the association appeared stronger with the infants' characteristics than with maternal childrearing practices and behaviors tested in this study.
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Otto, Saskia A., Sarah Simons, Joshua S. Stoll e Peter Lawson. "Making progress on bycatch avoidance in the ocean salmon fishery using a transdisciplinary approach". ICES Journal of Marine Science 73, n. 9 (28 aprile 2016): 2380–94. http://dx.doi.org/10.1093/icesjms/fsw061.
Testo completoAbstract (sommario):
Abstract Transdisciplinary research that crosses disciplinary boundaries and includes stakeholder collaboration is increasingly being used to address pressing and complex socio-ecological challenges in the Anthropocene. In fisheries, we see transdisciplinary approaches being employed to address a range of challenges, including bycatch where fine-scale data are collected by fishers to help advance spatial approaches in which fishing effort is shifted away from bycatch hotspots. However, the spatio-temporal overlap of morphologically undistinguishable fish stocks, some of which are depleted, is a major concern for some fisheries, including the Pacific Northwest troll Chinook salmon (Oncorhynchus tshawytscha) fishery. In this study, we develop and evaluate a transdisciplinary approach to avoid bycatch in the commercial Chinook salmon troll fishery off northern and central Oregon. Based on a unique genetic dataset collected by fishers, fine-scale patterns of stock distribution and spatial stock overlap were assessed. Two hotspots of weak Klamath stock in the study region were identified and related to bathymetry. Results were then fed into a simple bioeconomic model to evaluate costs and benefits of reallocating effort under two scenarios of allowable catch of a weak stock (Klamath). The scenarios demonstrate that effort reallocation could lead to a reduction in Klamath catch as well as to increases in net profit, but outcomes depend on the distance from the fleets' home port to the new fishing area. The output of the model at its current stage should be regarded strategically, providing a qualitative understanding of the types of best fleet strategies. Despite some challenges in transdisciplinarity discussed in this study and the present limitations to incorporate fine-scale changes of Chinook salmon stock distributions in management regulations, we contend that this approach to research has the potential to lead to improved management outcomes.
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Sakoulas, George, Matthew Geriak, Ravina Kullar, Kris Greenwood, Mackenzie Habib, Anuja Vyas, Mitra Ghafourian, Venkata Naga Kiran Dintyala e Fadi Haddad. "71. Use of Intravenous Immunoglobulin Therapy Reduces Progression to Mechanical Ventilation in COVID-19 Patients with Moderate to Severe Hypoxia". Open Forum Infectious Diseases 7, Supplement_1 (1 ottobre 2020): S166. http://dx.doi.org/10.1093/ofid/ofaa439.381.
Testo completoAbstract (sommario):
Abstract Background The majority of COVID-19 morbidity and mortality occurs in patients who progress to mechanical ventilation. Therefore, therapeutic interventions targeting the mitigation of this complication would markedly improve outcomes and reduce healthcare utilization. Methods Patients with COVID-19 from two hospitals in San Diego, California were randomized at a 1:1 ratio to receive standard of care (SOC) plus intravenous immunoglobulin (IVIG) at 0.5 g/kg/day x 3 days with solumedrol 40 mg 30 minutes before infusion (IVIG group) versus SOC alone. The primary composite endpoint was receipt of mechanical ventilation or death before receiving ventilation. Patients were followed until discharge to home or up to 30 days from time of enrollment. Results Sixteen patients received IVIG plus SOC and 17 SOC alone. The median age was 54 years for SOC and 57 years for IVIG. Median time from hospital admission to study enrollment was 1 day (range 0–4) for SOC and 2 days (range 0–8) for IVIG. APACHE II scores and Charlson comorbidity indices were similar for IVIG and SOC (median 8 vs 7 and 2 for both, respectively). Seven SOC patients achieved the composite endpoint (6 ventilated, 1 death) versus 2 IVIG patients (2 ventilated), p=0.12, Fisher exact test. Among the subgroup with an estimated A-a gradient of >200 mm Hg at time of enrollment, the IVIG group showed a lower rate of progression to the composite endpoint (2/14 vs 7/12, p=0.04 Fisher exact test), shorter median hospital length (11 vs 24 days, p=0.001 Mann Whitney U), and shorter median intensive care unit (ICU) stay (3 vs 13 days, p=0.005 Mann Whitey U). Conclusion This small, prospective, randomized, open-label study showed that when administered to hypoxic non-ventilated COVID-19 patients with an A-a gradient of >200 mm Hg (corresponding to a requirement of 6 liters O2 via nasal cannula to achieve an SpO2 of 92%), IVIG significantly decreased the rates of progression to mechanical ventilation, ICU length of stay, and total hospital length of stay. A Phase 3 prospective, randomized, placebo-controlled, multicenter trial is underway to further validate these findings. Disclosures George Sakoulas, MD, Octapharma (Grant/Research Support, Scientific Research Study Investigator)
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Rigby, P. Robin, e Yasunori Sakurai. "Multidimensional Tracking of Giant Pacific Octopuses in Northern Japan Reveals Unexpected Foraging Behaviour". Marine Technology Society Journal 39, n. 1 (1 marzo 2005): 64–67. http://dx.doi.org/10.4031/002533205787521730.
Testo completoAbstract (sommario):
Most marine populations are in decline (Pauly, 2000; Leon, 2003) and reports of stable or increasing stocks are viewed with some scepticism (Myers and Worm, 2003). Compensation for decreasing fish stocks by cephalopod populations has been theorized and reported (O'Dor, 1998; Chotiyaputta et al., 2002). Around Hokkaido Island (northern Japan), catch per unit effort (CPUE) of Enteroctopus dofleini is relatively stable (Hokkaido Fisheries Annual Report, 1986-2001). Decreasing inter-specific competition for food, reduced predation pressure by large fishes and a prevailing temperature regime are possible factors in the stability of the E dofleini catch rate; but so is the flexible behaviour of octopuses. Neural and behaviour studies (Young, 1961; Mather, 1994; Yamazaki et al., 2002) have alluded to the benefits of the adaptability of octopus behaviour, but no suggestions are as succinct as our findings during a recent radio acoustic tagging study where tagged octopuses stayed in smaller home ranges for longer periods of time than expected (Mather et al., 1985) while feeding off of a gill net. We propose that these findings have direct implications to understanding of the ecology of the species and are an example of why in situ monitoring provided by Radio Acoustic Positioning (RAP) technology is an essential part of the planning, and implantation of regional management plans and the development and monitoring of marine protected areas.
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Baral, Pratyusava, Soumendra Kishore Roy e Supratik Pal. "Prospects of probing dark energy with eLISA: Standard versus null diagnostics". Monthly Notices of the Royal Astronomical Society 500, n. 3 (29 ottobre 2020): 2896–907. http://dx.doi.org/10.1093/mnras/staa3346.
Testo completoAbstract (sommario):
ABSTRACT Gravitational waves from supermassive black hole binary mergers along with an electromagnetic counterpart have the potential to shed ‘light’ on the nature of dark energy in the intermediate redshift regime. Accurate measurement of dark energy parameters at intermediate redshift is extremely essential to improve our understanding of dark energy, and to possibly resolve a couple of tensions involving cosmological parameters. We present a Fisher matrix forecast analysis in the context of eLISA to predict the errors for three different cases: the non-interacting dark energy with constant and evolving equation of state (EoS), and the interacting dark sectors with a generalized parametrization. In all three cases, we perform the analysis for two separate formalisms, namely, the standard EoS formalism and the Om parametrization which is a model-independent null diagnostic for a wide range of fiducial values in both phantom and non-phantom regions, to make a comparative analysis between the prospects of these two diagnostics in eLISA. Our analysis reveals that it is wiser and more effective to probe the null diagnostic instead of the standard EoS parameters for any possible signature of dark energy at intermediate redshift measurements like eLISA.
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Temper, Leah. "Who gets the HANPP (Human Appropriation of Net Primary Production)? Biomass distribution and the bio-economy in the Tana Delta, Kenya". Journal of Political Ecology 23, n. 1 (1 dicembre 2016): 410. http://dx.doi.org/10.2458/v23i1.20243.
Testo completoAbstract (sommario):
The Tana Delta, on the east coast of Kenya near Somalia, comprises riverine mangrove forests, wetlands and rangelands and is home to a range of indigenous pastoralist, farmer and fisher communities, whose traditional multi-user livelihood strategies have helped preserve exceptional local biodiversity. This study assesses conflicts over biomass through an analysis of Human Appropriation of Net Primary Production (HANPP), an indicator used by system ecologists that quantifies human-induced changes on the productivity and harvest of biomass flows. HANPP is calculated by seeing how much of the net primary production (NPP) of biomass flows created through solar energy are appropriated by human activity, and how much is left in the ecosystems for other species. In this article we introduce calculations of the HANPP in political ecology by studying not only the distribution of biomass between humans and non-humans but also (and this is the main point) between different groups or social classes of humans. We also ask what alliances are being made to protect biodiversity and keep livelihoods intact. In a sugar cane plantation economy, biomass production and the proportion appropriated by humans may increase, the Orma pastoralists and the Pokomo farmers would be dispossessed, less biomass would be available for local 'wild' biodiversity, and a much larger proportion of the NPP would be exported as sugar or ethanol.Key words: Human appropriation of biomass; bioeconomy; biodiversity; property rights; pastoralists; sugar cane; wetlands.