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Journal articles on the topic "Centre Acanthes"
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Murail, Tristan. "Villeneuve-lès-Avignon Conferences, Centre Acanthes, 9–11 and 13 July 1992." Contemporary Music Review 24, no. 2-3 (April 2005): 187–267. http://dx.doi.org/10.1080/07494460500154889.
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Vieira, Caroline Evelin Nascimento Kluczynik, Larissa Soares Mariz, Carla Campos Muniz Medeiros, Bertha Cruz Enders, and Alexsandro Silva Coura. "Nursing care in childcare services: Acantose nigricans as a marker for metabolic risk." Revista Latino-Americana de Enfermagem 21, no. 6 (December 2013): 1220–27. http://dx.doi.org/10.1590/0104-1169.2870.2357.
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OBJECTIVE: to analyze the association between the presence of Acantose nigricans and metabolic changes in overweight adolescents, so as to ascertain the relevance of the identification of this marker in the nursing consultation. METHOD: a cross-sectional study undertaken between April 2009 and April 2010 with 118 adolescents who were service users of the Center for Child Obesity in Campina Grande in the Brazilian State of Paraíba (PB). The presence of Acantose nigricans, and the subjects' anthropometric measurements, were investigated. The following exams were made: insulin, triglycerides, HDL-Cholesterol, Glucose and the homeostatic model of assessment (HOMA-IR). RESULTS: there was association between the presence of Acantose nigricans and participants with insulin resistance (p=0.008), metabolic syndrome (p=0.031), elevated triglycerides (p=0.045) and altered HDL (p=0.002). CONCLUSIONS: the suggestion is supported that the detection/identification of Acantose nigricans may be used in the nursing consultation as a tool for identifying overweight adolescents with greater risk of metabolic changes.
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Desmania, Desy, Sugeng Prayitno Harianto, and Susni Herwanti. "Cinta Bahari Women's Group Participation on Mangrove Forest Conservation." Jurnal Sylva Lestari 6, no. 3 (October 2, 2018): 28. http://dx.doi.org/10.23960/jsl3628-35.
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Most area of Margasari village was mangrove forests. Therefore, Cinta Bahari Women’s Group, make mangrove forests as a source of life and their economic income. Cinta Bahari Women’s Group was a group of women who always be active in the processing and the utilization of non-timber mangrove forest products namely jeruju leaf (Acanthus Ilicifolius) and pedada fruit (Sonneratia Caseolaris) to serve as processed food ingredients. The purpose of this research was to identify the activities which were undertaken by cinta bahari women’s group of mangrove forest conservation. This research was conducted at Lampung Mangrove Center, Margasari Village, Labuhan Maringgai District, East Lampung regency by using purposive sampling method. The number of respondents was 41 people. Based on the result of research, the aspect of protection in the effort of conservation of mangrove forest was categorized good with percentage of 88% which was supported by the activities of plant protection jeruju (Acanthus ilicifolius) and fruit plants pedada (Sonneratia caseolaris) from disturbance of animals and human disturbance; preservation aspect was categorized good with percentage equal to 54% which was supported by the stitching and nursery activities of mangrove plants; utilization aspect was categorized good with percentage equal to 58% which was supported by the utilization of mangrove forests as processed foods, beverages and medicines.Keywords: Margasari village, Mangrove forests, Cinta bahari women’s group, mangrove forest conservation.
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Jerman, Mateja. "Srebrni zidni svijećnjaci cara Leopolda I. u franjevačkom samostanu na Trsatu." Ars Adriatica, no. 6 (January 1, 2016): 139. http://dx.doi.org/10.15291/ars.535.
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The aim of this paper is to publish and place in an art-historical context two silver wall candelabra with busts of classical antique figures surrounded by intertwined stylized acanthus leaves. The candelabra are kept in the Franciscan convent of Trsat. They were last documented in a photo-documentary campaign by Artur Schneider during the 1930s, and in 1974 they were added to the culturalheritage list as part of the convent's inventory. It is a very valuable set of silver wall candelabra, donated to the Franciscan convent of Trsat in 1693 by the Holy Roman Emperor Leopold I Habsburg (1658-1705). The author refers to the written sources confirming the commission of the candelabra and analyses the evolution of their peculiar typology. In their design and iconographic programme, judging by the various analogies and graphic models, they corresponded to the production of Augsburg goldsmiths. This hypothesis is supported by the hallmark of the city of Augsburg and another one indicating goldsmith Antoni Grill I, documented in that art centre in the period from 1668-1700.
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Tucker, Richard. "Age Validation Studies on the Spines of the Spurdog (Squalus Acanthias) Using Tetracycline." Journal of the Marine Biological Association of the United Kingdom 65, no. 3 (August 1985): 641–51. http://dx.doi.org/10.1017/s0025315400052486.
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Elasmobranchs, unlike teleosts, do not possess otoliths or scales suitable for age determination. Various skeletal structures of elasmobranchs have been used in an attempt to find a reliable ageing technique. These include the centra of Raja fusca (Ishiyama, 1951). R. eglanteria (Daiber, 1960), R. erinacea (Richards, Merriman & Calhoun, 1963) and Cetorhinus maximus (Parker & Stott, 1965). Yokota (1951, 1952) has described annual growth increments on the claspers of various elasmobranch species. Stevens (1975) made vertebral ring counts in the blue shark, Prionace glauca L. More recently Jones & Geen (1977a,b), using X-ray spectrometric analysis, have examined the vertebral circuli of dogfish found in British Columbia waters. Methods of age determination, using the spines of the spurdog (Squalus acanthias L.) have been described by Kaganovskaia (1933, 1937), Bonham et al. (1949) and Aasen (1961). All these authors assumed that the more or less regular series of dark bands or ‘rings’, extending from a white pigment-free base of the enamel to near the tip, were annual. Holden & Meadows (1962), on the basis of the internal and external features of the spines, concluded that the dark bands did represent annual growth increments. In particular, they argued that the dark bands were laid down during the winter when growth would be slowest, whereas the faster growth in the summer was represented by the light bands. Holden & Meadows (1962) identified several conditions, e.g. birth, double, false and spawning rings – that made interpretation of the ring structure and subsequent age determination difficult.
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Sagarese, Skyler R., Michael G. Frisk, Thomas J. Miller, Kathy A. Sosebee, John A. Musick, and Paul J. Rago. "Influence of environmental, spatial, and ontogenetic variables on habitat selection and management of spiny dogfish in the Northeast (US) shelf large marine ecosystem." Canadian Journal of Fisheries and Aquatic Sciences 71, no. 4 (April 2014): 567–80. http://dx.doi.org/10.1139/cjfas-2013-0259.
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Declines in abundance of commercially valuable groundfish have highlighted the ecological and commercial importance of previously underutilized elasmobranchs in the Northeast (US) shelf large marine ecosystem (NES LME). Seasonal distributions and ontogenetic habitats of one such species, spiny dogfish (Squalus acanthias), were investigated using Northeast Fisheries Science Center (NEFSC) bottom trawl survey data (1963–2009). Neonate, immature, and mature dogfish all selected warmer, more saline, and more southerly locations during spring compared with available locations. During autumn, larger dogfish occupied relatively warmer, shallower, and less saline waters while neonates selected higher salinities. There were strong ontogenetic patterns in habitats occupied. Contrary to expectation, geographic range contracted as abundance increased during autumn. This suggests that niche constraints override density-dependent effects, although detection of relationships within stages was limited by low statistical power. The proportion of mature female survey catch within the Mid-Atlantic Bight was significantly related to temperature, suggesting that environmental conditions surveyed may impact population trends. Collectively, these results highlight critical habitats, suggest mechanisms behind ontogenetic habitat selection, and provide insight into how changing environmental conditions may impact stock assessment.
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Dale, Svein. "Ecology of a Two-barred Crossbill (Loxia leucoptera) irruption to Norway in 2019–20: altitudinal migration and interspecific habitat differences." Ornis Norvegica 44 (September 7, 2021): 19–30. http://dx.doi.org/10.15845/on.v44i0.3265.
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Cover photo: A male Two-barred Crossbill (Loxia leucoptera). Photo: Frode Falkenberg.
Two-barred Crossbills (Loxia leucoptera) have cyclic irruptions to Norway, but are generally uncommon and breeding is rare. Here I analyse data on a large irruption occurring in 2019–20 to assess the magnitude of the irruption and the ecological niche of the species. The irruption lasted one year, starting in July 2019 and ending in June 2020. Total numbers reported by birdwatchers to the website of the National Biodiversity Information Centre in Norway were ca. 7,000 individuals. Breeding indications were reported from nearly 100 sites. Analyses of elevation of records indicated that birds were often seen at low elevations before the breeding season in February–June, but moved to higher elevations during the breeding season. In a focal study area in SE Norway, breeding season surveys along elevational gradients indicated that Two-barred Crossbills occurred at higher elevations, and often close to summits of hills, perhaps representing preferences for more open forest habitats. Two-barred Crossbills often co-occurred with other seed-eating bird species, but presence was more closely related to numbers of Common Redpoll (Acanthis flammea), than to Eurasian Siskin (Spinus spinus) or cogeneric Common Crossbill (L. curvirostra). Similarly, the Common Redpoll also increased strongly in abundance with elevation, whereas the other two species did so to a lesser degree. These data suggest that the Two-barred Crossbill favors montane forests during the breeding season, and thereby has a different niche than the Common Crossbill which is distributed more widely across all elevations.
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., Supriyanto, Indriyanto ., and Afif Bintoro. "Inventarisasi Jenis Tumbuhan Obat Di Hutan Mangrove Desa Margasari Kecamatan Labuhan Maringgai Lampung Timur." Jurnal Sylva Lestari 2, no. 1 (April 4, 2014): 67. http://dx.doi.org/10.23960/jsl1267-76.
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Mangrove forest in Lampung Mangrove Center (LMC) Margasari village at East Lampung is one area that still has good condition to keep a variety of potential to be explored such as medicinal plants.Purpose of this study was to determine of species, diversity, and functional properties of mangrove plants for medicine.Research conducted in April 2012 in village 12 Translok at Margasari village East Lampung.Data retrieval is using method checkered lines, and interviews with the public, as well as literature.Number of sample plots used 12 pieces.Data were analyzed using the formula density, relative density, frequency, relative frequency, important value index, and diversity index Shannon.Based on the result of the research have been known 7 species of plants as medicine, among others: api-api (Avicennia marina) to cure rheumatism and toothache; jeruju (Acanthus ilicifolius) cure for cancer and diabetic; nipa (Nypa fruticans) medication for asthma and diabetes; bakau (Rhizophora apiculata) for antiseptic; beluntas (Pluchea indica) for body odor; jenu (Derris trifoliata) for a laxative; and tapak kuda (Ipomoea pescaprae) to cure wounds and ulcers.Api-api is a dominant plant and widest spread because it has an important index as value high as 144,24% and frequency 67,5%. Beluntas plant has the highest density of 12.708,33 individual/ha.Mangrove forest Margasari village at village 12 Translok have low diversity, because the calculation of the index obtained values Shannon H’=0, 44. Key words : inventory, mangrove forest, medicinal plant
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Sagarese, Skyler R., Michael G. Frisk, Robert M. Cerrato, Kathy A. Sosebee, John A. Musick, and Paul J. Rago. "Application of generalized additive models to examine ontogenetic and seasonal distributions of spiny dogfish (Squalus acanthias) in the Northeast (US) shelf large marine ecosystem." Canadian Journal of Fisheries and Aquatic Sciences 71, no. 6 (June 2014): 847–77. http://dx.doi.org/10.1139/cjfas-2013-0342.
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Increased commercial importance of spiny dogfish (Squalus acanthias) combined with an often debated, and controversial, ecological impact has warranted an investigation of the relationship among distribution, environment, and prey to better understand the species ecology and inform management. To elucidate mechanisms behind distributional changes, we modeled seasonal occurrence and abundance of neonate, immature, and mature spiny dogfish as functions of abiotic and biotic factors using generalized additive models and Northeast Fisheries Science Center bottom trawl survey data. Significant nonlinear relationships were widespread throughout dogfish stages and seasons. Seasonal occurrence was tightly linked to depth and bottom temperature, with year and Julian day influential for some stages. While these factors also influenced abundance, ecological factors (e.g., squid abundances) significantly contributed to trends for many stages. Potential impacts of climate change were evaluated by forecasting distributions under different temperature scenarios, which revealed higher regional probabilities of occurrence for most stages during a warmer than average year. Our results can be used to better understand the relationship between sampling periods and movement drivers to survey catchability of the population in the Northeast (US) shelf large marine ecosystem.
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Yang, T., S. J. Forrest, N. Stine, Y. Endo, A. Pasumarthy, H. Castrop, S. Aller, J. N. Forrest, J. Schnermann, and J. Briggs. "Cyclooxygenase cloning in dogfish shark, Squalus acanthias, and its role in rectal gland Cl secretion." American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 283, no. 3 (September 1, 2002): R631—R637. http://dx.doi.org/10.1152/ajpregu.00743.2001.
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The present studies were carried out with the aims to determine the cDNA sequence for cyclooxygenase (COX) in an elasmobranch species and to study its role in regulation of chloride secretion in the perfused shark rectal gland (SRG). With the use of long primers (43 bp) derived from regions of homology between zebrafish and rainbow trout COX-2 genes, a 600-bp product was amplified from SRG and was found to be almost equally homologous to mammalian COX-1 and COX-2 (65%). The full-length cDNA sequence was obtained by 5′-RACE and by analyzing an EST clone generated by the EST Project of the Mt. Desert Island Biological Laboratory Marine DNA Sequencing Center. The longest open reading frame encodes a 593-amino acid protein that has 68 and 64% homology to mammalian COX-1 and COX-2, respectively. The gene and its protein product is designated as shark COX (sCOX). The key residues in the active site (Try385, His388, and Ser530) are conserved between the shark and mammalian COX. sCOX contains Val523 that has been shown to be a key residue determining the sensitivity to COX-2-specific inhibitors including NS-398. The mRNA of sCOX, detected by RT-PCR, was found in all tissues tested, including rectal gland, kidney, spleen, gill, liver, brain, and heart, but not in fin. In the perfused SRG, vasoactive intestinal peptide (VIP) at 5 nM induced rapid and marked Cl− secretion (basal: <250 μeq · h−1 · g−1; peak response: 3,108 ± 479 μeq · h−1 · g−1). In the presence of 50 μM NS-398, both the peak response (2,131 ± 307 μeq · h−1 · g−1) and the sustained response to VIP were significantly reduced. When NS-398 was removed, there was a prompt recovery of chloride secretion to control values. In conclusion, we have cloned the first COX in an elasmobranch species (sCOX) and shown that sCOX inhibition suppresses VIP-stimulated chloride secretion in the perfused SRG.
Books on the topic "Centre Acanthes"
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Gilly, Cécile. Acanthes an xv: Composer, enseigner, jouer, la musique d'aujourd'hui. Fondettes: Van de Velde, 1991.
Find full textBook chapters on the topic "Centre Acanthes"
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"Biology and Management of Dogfish Sharks." In Biology and Management of Dogfish Sharks, edited by Michael G. Pawson, James R. Ellis, and Helen Dobby. American Fisheries Society, 2009. http://dx.doi.org/10.47886/9781934874073.ch32.
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Abstract.—This paper summarizes the history of the fisheries that have exploited spiny dogfish <em>Squalus acanthias </em>(also known as spurdog) in the northeast Atlantic since the early 20th century, describes the species’ stock structure, and indicates through recent assessments that the stock of spiny dogfish is severely depleted. We review the background to the management of elasmobranch fisheries in European seas, discuss the reasons why there has been a lack of effective management of the dogfish fishery, and suggest measures that might be used to aid stock recovery.
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"Biology and Management of Dogfish Sharks." In Biology and Management of Dogfish Sharks, edited by Paul J. Rago and Katherine A. Sosebee. American Fisheries Society, 2009. http://dx.doi.org/10.47886/9781934874073.ch31.
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Abstract.—Following intense harvests by distant-water fleets before 1975, populations of spiny dogfish Squalus acanthias in the Northwest Atlantic increased steadily in abundance during the mid-1970s and 1980s. Peak abundance in the early 1990s was short-lived as the United States commercial fleet began a large-scale fishery on mature female dogfish. Between 1989 and 1999, approximately 250,000 metric tons of female spawning stock was removed, reducing the stock to about 30% of B<sub>MSY</sub> levels. Abundance of male dogfish, however, was relatively unaffected by the fishery. The average size of mature female dogfish declined by more than 10 cm and the average length of juveniles declined as well. Recruitment during 1997 to 2003 was the lowest in the 1968–2006 time series. Recruitment in 2006 was low despite a very high catch rate of mature females in the spring survey by the Northeast Fisheries Science Center. The ratio of mature male to females increased from about 2:1 prior to the directed fishery to about 7:1 by 2001.
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"Biology and Management of Dogfish Sharks." In Biology and Management of Dogfish Sharks, edited by Richard D. Brodeur, Ian A. Fleming, Jacyln M. Bennett, and Matthew A. Campbell. American Fisheries Society, 2009. http://dx.doi.org/10.47886/9781934874073.ch4.
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Abstract.—Our understanding of the spiny dogfish <em>Squalus acanthias </em>of the northeastern Pacific is based almost exclusively on nearshore populations from enclosed regions (e.g., Strait of Georgia, Hecate Strait, and Puget Sound), with little attention given to more offshore populations along the open coast. Our purpose here was to characterize the summer distribution and diet of dogfish off the Washington and Oregon coasts by means of two fishery surveys: the National Marine Fisheries Service (NMFS) triennial shelf groundfish survey, 1977–2004, and the NMFS/Oregon State University juvenile salmon survey, 1998–2002. Dogfish catches were patchy throughout the entire period and showed a broad distributional range along the Washington and Oregon coasts. The highest abundances occurred in shallow waters (55–184 m) off the northern Washington and central Oregon coasts. Around the Columbia River plume, dogfish catch per unit of effort was significantly related to salinity and surface temperature patterns, but not to chlorophyll concentrations. Dogfish consumed a variety of prey, including both pelagic and benthic taxa, and with increasing size exhibited a shift in their diet to more fish and larger prey overall.
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"Biology and Management of Dogfish Sharks." In Biology and Management of Dogfish Sharks, edited by Cindy A. Tribuzio, Vincent F. Gallucci, and Gregory G. Bargmann. American Fisheries Society, 2009. http://dx.doi.org/10.47886/9781934874073.ch17.
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Abstract.—The fishery for spiny dogfish <em>Squalus acanthias </em>in Washington State has been ongoing for over a century. Management efforts have historically been limited and recent interest in increasing management efforts has led to renewed interest in the biology of the species. This project was undertaken to aid in management by describing the reproductive cycle of the dogfish in Puget Sound. Reproductive tracts were sampled from 170 male and 358 female dogfish from the catch of a commercial trawler over one year. Size at 50% maturity was 89.9 cm for females and 74.1 cm for males (total length extended). Reproductive stages were developed for adult females based on the proportion of yolk absorbed by the developing embryo. Size, weight, and appearance changes in the reproductive tract for both males and females throughout maturation and reproduction are described. There did not appear to be a significant seasonality to the reproductive timing, in that the onset of pregnancy and pupping were observed year round, however, peaks in activity were observed in December for the onset of pregnancy and October for pupping.
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"Biology and Management of Dogfish Sharks." In Biology and Management of Dogfish Sharks, edited by Christina L. Conrath and Robert J. Foy. American Fisheries Society, 2009. http://dx.doi.org/10.47886/9781934874073.ch10.
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Abstract.—Data from research surveys conducted by the National Marine Fisheries Service’s (NMFS) Alaska Fisheries Science Center and the International Pacific Halibut Commission (IPHC) were examined along with catch data from NMFS’s North Pacific Groundfish Observer Program to determine the distribution, abundance, and status of spiny dogfish <em>Squalus acanthias </em>in Alaska. Dogfish are present in the Gulf of Alaska, Bering Sea, and Aleutian Islands but survey and observer data indicate they are most abundant in the central and eastern Gulf of Alaska in waters less than 200 m deep. All data sources indicate that dogfish have increased in abundance in the Gulf of Alaska in recent years. Log-transformed catch per unit effort (CPUE) of dogfish calculated from the NMFS trawl survey data ranged from 0.47 sharks/km2 in 1984 to 0.91 sharks/km2 in 2007, with a peak of 1.17 sharks/km2 in 2003. Log-transformed CPUE of spiny dogfish calculated from the NMFS longline survey data ranged from 0.041 sharks/100 hooks in 1979 to 0.16 sharks/100 hooks in 2007, with peaks in abundance of 0.23 sharks/100 hooks in 1983 and 1998. Log-transformed CPUE of dogfish calculated from the IPHC annual longline survey data showed a similar trend and ranged from 0.84 sharks/100 hooks in 1997 to 1.18 sharks/100 hooks in 2006, with a peak value of 1.38 sharks/100 hooks in 2003. Estimates of the incidental catch of dogfish by Alaska fisheries in the Gulf of Alaska calculated from NMFS observer data from 1990 to 2007 were variable and ranged from 140 to 865 metric tons (mt), with peak values of over 650 mt in years 1998, 1999, 2006, and 2007. Dogfish are currently managed as a member of the “other species” complex by the North Pacific Fishery Management Council in Alaska waters. The increasing abundance of this species in the Gulf of Alaska in recent years and the increasing probability of a fishery developing may necessitate a species-specific management strategy for dogfish in Alaska waters.
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Ling, Roger, and Lesley Ling. "I. 10. 4: CASA DEL MENANDRO." In The Insula of the Menander at Pompeii. Oxford University Press, 2005. http://dx.doi.org/10.1093/oso/9780199266951.003.0009.
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In its Final form, the CASA Del Menandro was adorned with decorations which can be ascribed (leaving aside a few which are too simple or too damaged to be classified at all) to the late Second and Fourth Styles (see Figs. 2–3). Remains from other phases will be considered in the next section but none of these were visible in AD 79. The First Style pavements and painted stuccowork in the rooms excavated beneath the floor of room 18 (Figs. 27B, 64; Pl. 1) had of course been buried before AD 79, and they probably belonged to a separate house anyway. A piece of a First (or early Second) Style dado carrying a curtain motif, preserved inside the cupboard 10 (Fig. 27A), belongs to a phase when this space was a passage; it would have been out of sight in subsequent periods. Other remains of similarly early phases in the atrium area are chance survivals beneath later plaster. The only remnant of a Third Style decoration (Fig. 93B; Pl. 15) is on a fragment of plaster found (probably) in the pit in passage P1; and it clearly derives from a painted scheme which had been dismantled before the final years. All that was visible in 79, then, was work from the third quarter of the first century BC and the third quarter of the first century AD—what we have classified in terms of the structural history as the end of Phase 3 and Phase 5. The late-Second Style paintings and stuccoes are confined to the southern arm of the peristyle and the bath-suite. In the peristyle there is a relatively well-preserved painted scheme of trees seen through arched openings on the walls of exedra 25 (Col. Pl. 39; Figs. 77– 9) and a stucco decoration with birds in spiralling acanthus tendrils in the semi-dome of exedra 24 (Fig. 89D; Col. Pl. 38; Pl. 13); it appears that a similar stucco decoration adorned the semi-dome of exedra 22, but only a fragment of this survives.
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"Biology and Management of Dogfish Sharks." In Biology and Management of Dogfish Sharks, edited by Alexander G. Andrews and Robert J. Foy. American Fisheries Society, 2009. http://dx.doi.org/10.47886/9781934874073.ch24.
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Abstract.—Spiny dogfish <em>Squalus acanthias </em>biomass has increased in the Gulf of Alaska, yet little is known about the ecological niche that dogfish fill in this ecosystem. Trophic position is an important indicator of the ecological role of an organism. To explore the trophic position of dogfish we analyzed the nitrogen and carbon stable isotope ratios of 60 dogfish from five locations between Washington and the Gulf of Alaska. The mean δ<sup>15</sup>N values for dogfish ranged from 12.0‰ (central Gulf of Alaska) to 13.4‰ (Howe Sound, British Columbia) and the mean δ<sup>13</sup>C values ranged from –21.3‰ (Yakutat Bay, Alaska) to –17.9‰ (Puget Sound, Washington). Sites to the north tended to be significantly depleted in the heavy isotopes of both nitrogen and carbon. The differences in nitrogen isotope ratios among sites were attributed to potential changes in dogfish feeding behavior and trophic position. Differences in carbon isotope ratios suggested that dogfish utilize different food webs along the northeastern Pacific Ocean shelf. Additionally it was hypothesized that feeding differentially in offshore versus inshore food webs or targeting pelagic versus benthic prey species may explain the isotopic variability. These results are preliminary and require additional tests before conclusions can be made about the trophic position of dogfish in this region. Future work will explore stable isotope variability at lower trophic levels to test the hypothesis that entire food webs are isotopically shifted owing to differences in isotopic fractionation at the base of the food web. Also, trophic level differences among dogfish size classes and between sexes will be explored among a greater diversity of locations to better describe the ecological consequences of increased biomass of dogfish in the northeastern Pacific Ocean.
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"Biology and Management of Dogfish Sharks." In Biology and Management of Dogfish Sharks, edited by Steven E. Campana, Warren Joyce, and David W. Kulka. American Fisheries Society, 2009. http://dx.doi.org/10.47886/9781934874073.ch18.
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Abstract.—As part of an intensive study of spiny dogfish <em>Squalus acanthias </em>off the Atlantic coast of Canada, we studied the sexual maturation and growth of dogfish collected on research surveys and as part of the commercial fishery. Sexually mature and pregnant females were distributed throughout the waters of southwest Nova Scotia during the summer and fall but moved offshore to deeper waters in the winter. Juveniles were most abundant off Georges Bank and near the edge of the Scotian Shelf during the winter. The fork length at 50% maturity for males was 55.5 cm at age 10, while that for females was 72.5 cm at age 16. Free embryos were observed in 62% of all pregnant females (<em>n </em>= 1,491), the number of embryos increasing with the size of the female. Free embryos first became apparent in June at a fork length of 16 cm and would be expected to reach their birth size of 22–25 cm during the winter. Validated ages based on spine growth bands indicated a longevity of 31 years (<em>n </em>= 525). Males and females grew at similar rates until the size and age of male maturity, after which male growth rate slowed considerably. Two-parameter von Bertalanffy growth equations using a fixed size at birth gave <em>L<sub></em>∞</sub> = 78.0 and <EM>K </EM>= 0.099 for the males and <em>L<sub></em>∞</sub> = 119.5 and <EM>K </EM>= 0.042 for the females. Atlantic dogfish appear to grow more quickly and die at a younger age than do Northeast Pacific dogfish. Small amounts of offshore pupping in southern Nova Scotia waters probably represent the northern limits of an extended distribution centered in U.S. waters. Although they probably originate from the same population, dogfish living in the Gulf of St. Lawrence and off Newfoundland may be functionally isolated from dogfish found further south. Our results and published tagging studies suggest that both resident and migratory components of the Northwest Atlantic population occupy Canadian waters.