Genetic structure of the Common Eider in the western Aleutian Islands prior to fox eradication

The Condor
By: , and 



Since the late 18th century bird populations residing in the Aleutian Archipelago have been greatly reduced by introduced arctic foxes (Alopex lagopus). We analyzed data from microsatellite, nuclear intron, and mitochondrial (mtDNA) loci to examine the spatial genetic structure, demography, and gene flow among four Aleutian Island populations of the Common Eider (Somateria mollissima) much reduced by introduced foxes. In mtDNA, we found high levels of genetic structure within and between island groups (ΦST = 0.643), but we found no population subdivision in microsatellites or nuclear introns. Differences in genetic structure between the mitochondrial and nuclear genomes are consistent with the Common Eider's breeding and winter biology, as females are highly philopatric and males disperse. Nevertheless, significant differences between islands in the mtDNA of males and marginal significance (P =0.07) in the Z-linked locus Smo 1 suggest that males may also have some level of fidelity to island groups. Severe reduction of populations by the fox, coupled with females' high philopatry, may have left the genetic signature of a bottleneck effect, resulting in the high levels of genetic differentiation observed in mtDNA (ΦST = 0.460–0.807) between islands only 440 km apart. Reestablishment of the Common Eider following the fox's eradication was likely through recruitment from within the islands and bolstered by dispersal from neighboring islands, as suggested by the lack of genetic structure and asymmetry in gene flow between Attu and the other Near Islands.

Study Area

Publication type Article
Publication Subtype Journal Article
Title Genetic structure of the Common Eider in the western Aleutian Islands prior to fox eradication
Series title The Condor
DOI 10.1525/cond.2012.110054
Volume 115
Issue 1
Year Published 2013
Language English
Publisher Cooper Ornithological Society
Contributing office(s) Alaska Science Center Biology WTEB
Description 12 p.
First page 28
Last page 39
Country Russia, United States
Other Geospatial Aleutian Islands
Online Only (Y/N) N
Additional Online Files (Y/N) N
Google Analytic Metrics Metrics page
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