title: Genetic diversity and population parameters of sea otters, Enhydra lutris, before fur trade extirpation from 1741-1911.
abstract: All existing sea otter, Enhydra lutris, populations have suffered at least one historic population bottleneck stemming from the fur trade extirpations of the eighteenth and nineteenth centuries. We examined genetic variation, gene flow, and population structure at five microsatellite loci in samples from five pre-fur trade populations throughout the sea otter's historical range: California, Oregon, Washington, Alaska, and Russia. We then compared those values to genetic diversity and population structure found within five modern sea otter populations throughout their current range: California, Prince William Sound, Amchitka Island, Southeast Alaska and Washington. We found twice the genetic diversity in the pre-fur trade populations when compared to modern sea otters, a level of diversity that was similar to levels that are found in other mammal populations that have not experienced population bottlenecks. Even with the significant loss in genetic diversity modern sea otters have retained historical structure. There was greater gene flow before extirpation than that found among modern sea otter populations but the difference was not statistically significant. The most dramatic effect of pre fur trade population extirpation was the loss of genetic diversity. For long term conservation of these populations increasing gene flow and the maintenance of remnant genetic diversity should be encouraged.
authors.affiliation: Research/Animal Health, Seattle Aquarium, Seattle, Washington, United States of America. s.larson@seattleaquarium.org
authors.forename: Shawn
authors.initials: S
authors.lastname: Larson
authors.forename: Ron
authors.initials: R
authors.lastname: Jameson
authors.forename: Michael
authors.initials: M
authors.lastname: Etnier
authors.forename: Terry
authors.initials: T
authors.lastname: Jones
authors.forename: Roberta
authors.initials: R
authors.lastname: Hall
mesh_terms: D000818:Animals; D001842:Bone and Bones / Q000378:metabolism; D003132:Commerce; D004247:DNA / Q000235:genetics; D053476:Extinction, Biological; D051456:Gene Flow; D005787:Gene Frequency; D056426:Genetic Loci / Q000235:genetics; D014644:Genetic Variation; D005838:Genotype; D006197:Hair; D018895:Microsatellite Repeats / Q000235:genetics; D010041:Otters / Q000235:genetics*; D011157:Population Dynamics
chemical_list: D004247:DNA