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Seasonal movements of immature Kemp's ridley sea turtles (Lepidochelys kempii) in the northern gulf of Mexico 下载免费PDF全文
Andrew T. Coleman Jonathan L. Pitchford Helen Bailey Moby Solangi 《水产资源保护:海洋与淡水生态系统》2017,27(1):253-267
- Seasonal movements and core habitat areas of immature Kemp's ridley sea turtles (Lepidochelys kempii) in the northern Gulf of Mexico were tracked via satellite telemetry. Tagged turtles were incidentally captured by recreational fishermen and rehabilitated at the Institute for Marine Mammal Studies in Gulfport, Mississippi.
- The average size of the core habitat areas (50% KDE (kernel density estimation)) was 1660.2 km2 ± 3438.2 SD. Turtles displayed strong intra‐ and inter‐annual site fidelity to the Mississippi Sound during the spring, summer, and autumn months. During the winter months, most turtles, probably influenced by water temperatures, migrated to nearshore waters of Louisiana on either side of the Mississippi River Delta. However, other migration strategies were also observed.
- Overall, these data indicate that the Mississippi Sound is an important developmental habitat for this critically endangered species. In addition, their wintering grounds in Louisiana are utilized by adult Kemp's ridleys and other sea turtle species as foraging grounds and migratory corridors. The high use of these areas by sea turtle populations increases the potential for negative impacts from anthropogenic disturbances (e.g. shrimp trawling, oil production, hypoxia) that occur there.
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Effect of an intensive mechanical removal effort on a population of non‐native rainbow trout Oncorhynchus mykiss in a South African headwater stream 下载免费PDF全文
Jeremy Shelton Olaf Weyl Johannes Van Der Walt Sean Marr Dean Impson Kristine Maciejewski Donovan Tye Helen Dallas Karen Esler 《水产资源保护:海洋与淡水生态系统》2017,27(5):1051-1055
- Invasions by non‐native species can compromise the conservation value of otherwise pristine headwater streams. While both developed and developing countries recognize this threat, few of the latter have suitable budgets to implement control programmes.
- This study assessed the effectiveness of a mechanical project to remove non‐native rainbow trout Oncorhynchus mykiss from a 6 km section of the upper Krom River, a small headwater stream in the Cederberg Mountains in South Africa's Cape Floristic Region (CFR).
- From October 2013 to February 2014, 354 O. mykiss were removed by angling (58%), fyke netting (28%) and gill netting (14%). This resulted in a marked reduction, but not eradication, of the O. mykiss population (fish relative abundance decreased from 0.53 ± 0.09 fish per net per night in October 2013 to 0.21 ± 0.09 fish per net per night in February 2014). Following the cessation of manual removals, the relative abundance of O. mykiss had increased to 0.56 ± 0.18 fish per net per night by March 2016, suggesting that without sustained removal effort, the population will rapidly return to its pre‐removal abundance level.
- Further work is needed to refine the methodology and test the effectiveness of mechanical removal of non‐native freshwater fish in a variety of ecological settings in the CFR. This approach holds potential for meeting the dual goals of reducing the ecological impacts of non‐native fishes and generating employment opportunities in line with the policy objectives of developing nations.
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Helen L. Orbell John S. Munday Geoffrey M. B. Orbell Craig E. Griffin 《Veterinary dermatology》2020,31(5):401-403
A 12‐year‐old spayed English pointer dog developed multiple skin lesions including pigmented viral plaques, basal cell carcinomas, squamous cell carcinomas and trichoblastomas. Canine papillomavirus type 3 was detected in multiple lesions suggesting common aetiology.
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Nicola J Grint Helen R Whay Thierry Beths Kathy Yvorchuk Joanna C Murrell 《Veterinary anaesthesia and analgesia》2015,42(2):205-214
ObjectiveTo evaluate a thermal nociceptive threshold (TNT) testing device in the donkey, and the influence of potential confounding factors on TNTs.AnimalsTwo groups (Group 1 and Group 2) of eight castrated male donkeys aged 4–9 years, weighing 105–170 kg.MethodsTNTs were measured by heating a thermal probe on skin until an end-point behaviour (threshold temperature) or a cut-out temperature (51 °C) was reached. The withers and the dorsal aspect of the distal limb were used as sites for TNT testing. The effects on TNT of different confounding factors: the limb tested; rate of heating; and ambient temperature were evaluated. Data were analyzed using general linear models, and Mann-Whitney tests, p < 0.05 was considered significant.ResultsEnd-point behaviours (skin twitch or donkey looking at test device) when the thermal probe heated the withers were observed in approximately half of tests. TNT was (mean ± SD) 46.8 ± 2.85 °C. Subsequently the limb was evaluated as the test site in Group 1 followed by Group 2 donkeys; end-point behaviour being a foot-lift. In Group 1, 72% of tests ended in an end-point behaviour but the response rate was lower in Group 2 (20%), although TNTs were similar [(47.6 ± 3.3) and (47.3 ± 3.0) °C respectively] for responding animals. Rate of heating, ambient temperature and laterality (right or left) did not affect thresholds, but mean TNT was significantly higher in the forelimb (48.5 ± 2.8 °C) than the hind limb (47.4 ± 2.8 °C) (p = 0.012).ConclusionsWhen a thermal probe cut-out temperature of 51 °C was used in TNT testing in the donkey a high proportion of tests did not produce an identifiable end point behaviour. Higher cut-out temperatures damaged the skin. Under these conditions, thermal nociceptive threshold testing appears not be an appropriate analgesiometry technique in the donkey.Clinical relevanceTNT testing under these conditions is not suitable form of analgesiometry for donkeys. 相似文献
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Richard Thomas B. Pavia Janet S. Estacion 《Journal of the World Aquaculture Society》2019,50(1):219-230
Coral aquaculture is viewed as a sustainable method of providing colonies for use in the aquarium trade, pharmacological studies, and coral reef rehabilitation. The production of large, healthy specimens depends on providing conditions that mimic or surpass natural reef environments. Materials with a high degree of variability in physical and chemical properties are utilized as substrates in coral aquaculture, but until fragment–substrate interactions are isolated and independently studied, the possible inhibitory and facilitative effects of each material will remain unclear. To understand potential key roles that substrates can play in coral culture, a comparison was made about the role of various materials on fragment survival and growth. The experiment examined the interactions between isolates of a common scleractinian coral, Galaxea fascicularis, and six commonly used substrates (coral rock, terracotta, polyvinyl chloride, steel, rubber tire, and concrete) and how these affected survival and growth. No differences were observed in the survival, colony size, and polyp production of the resulting microcolonies. The results show that, for G. fascicularis, growth is not affected by substrate type. The results demonstrate the use of a wide variety of materials for the successful aquaculture of scleractinian corals. 相似文献
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Distribution,characteristics and condition of Arctic charr (Salvelinus alpinus) spawning grounds in a differentially eutrophicated twin‐basin lake 下载免费PDF全文
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恶劣天气后收获的小麦非常潮湿,往往不适合作为人类食品的原料使用。因为这种收获条件常常会导致小麦发芽以及含有高水平的淀粉酶和蛋白酶,而这些酶会影响烘焙食品的大小,降低面筋的强度。结果,此类受损的小麦可能会被销往动物饲料市场。 相似文献