Variation in the mitochondrial control region in the Juan Fernandez fur seal (Arctocephalus philippii)

The Juan Fernandez fur seal (Arctocephalus philippii) was allegedly extreme ly abundant, numbering as many as 4 million prior to sealing which continue d from the late 17th to the late 19th century. By the end of the sealing er a the species was thought to be extinct until they were rediscovered at Ale jandro Selkirk Island in 1965, Historic records would suggest that the spec ies underwent a substantial population bottleneck as a result of commercial sealing, and from population genetic theory we predicted that the genetic variability in the species would be low. We compared the mtDNA control regi on sequence from 28 Juan Fernandez fur seals from two islands in the Juan F ernandez Archipelago (Chile). Contrary to expectation, we found that variat ion in the Juan Fernandez fur seals is not greatly reduced in comparison to other pinniped taxa, especially given the apparent severity of the bottlen eck they underwent, We also determined minor, but significantly different h aplotype frequencies among the populations on the two islands (Alejandro Se lkirk and Robinson Crusoe Islands), but no difference in their levels of va riability. Such differences may have arisen stochastically via a recent fou nder event from Alejandro Selkirk to Robinson Crusoe Island or subsequent g enetic drift.