Otters
Mostrando 13-18 de 18 artigos, teses e dissertações.
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13. Causes and consequences of marine mammal population declines in southwest Alaska: a food-web perspective
Populations of sea otters, seals and sea lions have collapsed across much of southwest Alaska over the past several decades. The sea otter decline set off a trophic cascade in which the coastal marine ecosystem underwent a phase shift from kelp forests to deforested sea urchin barrens. This interaction in turn affected the distribution, abundance and product
The Royal Society.
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14. Genetic consequences of population decline in the European otter (Lutra lutra): an assessment of microsatellite DNA variation in Danish otters from 1883 to 1993.
The European otter (Lutra lutra) was common in Denmark until the 1960s, but its present distribution encompasses only a minor part of the country. The aim of this study was to assess whether the recent population decline has resulted in loss of genetic variability and to gain further insight into the dynamics of the population decline. This was done by analy
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15. Genotypes of Cryptosporidium Species Infecting Fur-Bearing Mammals Differ from Those of Species Infecting Humans
Of 471 specimens examined from foxes, raccoons, muskrats, otters, and beavers living in wetlands adjacent to the Chesapeake Bay, 36 were positive for five types of Cryptosporidium, including the C. canis dog and fox genotypes, Cryptosporidium muskrat genotypes I and II, and Cryptosporidium skunk genotype. Thus, fur-bearing mammals in watersheds excreted host
American Society for Microbiology.
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16. Sequential megafaunal collapse in the North Pacific Ocean: An ongoing legacy of industrial whaling?
Populations of seals, sea lions, and sea otters have sequentially collapsed over large areas of the northern North Pacific Ocean and southern Bering Sea during the last several decades. A bottom-up nutritional limitation mechanism induced by physical oceanographic change or competition with fisheries was long thought to be largely responsible for these decli
National Academy of Sciences.
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17. Molecular Characterization of Microsporidia Indicates that Wild Mammals Harbor Host-Adapted Enterocytozoon spp. as well as Human-Pathogenic Enterocytozoon bieneusi
Over 13 months, 465 beavers, foxes, muskrats, otters, and raccoons were trapped in four counties in eastern Maryland and examined by molecular methods for microsporidia. A two-step nested PCR protocol was developed to amplify a 392-bp fragment of the internal transcribed spacer region of the rRNA gene of Enterocytozoon spp., with the use of primers complemen
American Society for Microbiology.
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18. Evolutionary consequences of food chain length in kelp forest communities.
Kelp forests are strongly influenced by macroinvertebrate grazing on fleshy macroalgae. In the North Pacific Ocean, sea otter predation on macroinvertebrates substantially reduces the intensity of herbivory on macroalgae. Temperate Australasia, in contrast, has no known predator of comparable influence. These ecological and biogeographic patterns led us to p