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Because size reduced, or bottlenecked, populations are more prone to adverse events, the detection of genetic bottleneck signatures in wildlife species is highly relevant for conservation. Here we applied 11 microsatellite markers to the endangered Siberian tiger (Panthera tigris altaica) using tissue and blood samples of animals from the Primorsky region of the Russian Far East. Excess heterozygosity and mode shift in allele frequencies tests were positive, while the M-ratio test was negative, indicating the like- lihood of a contemporary rather than a historical population bottleneck. The recent genetic population bottleneck could be attributed to the well-documented demographic collapse of the Siberian tiger pop- ulation in the 1940s, when population size hit bottom with 20–30 surviving animals. The mean effective population size Ne was 14 Siberian tigers (CI95 : 12–25 animals), and the effective population size/census size ratio (Ne /N ratio) was 0.028. This is the first molecular evidence of a recent Siberian tiger population bottleneck, which is of great interest for further conservation and management plans of the highly endan- gered largest felid species, while the worryingly low effective population size challenges the optimism for the recovery of the huge Siberian cat.

The present study examined the relationship among individual Sarcoptes scabiei mites from 13 wild mammalian populations belonging to nine species in four European countries using the second internal transcribed spacer (ITS-2) of nuclear ribosomal DNA (rDNA) as genetic marker. The ITS-2 plus primer flanking 5.8S and 28S rDNA (ITS-2+) was amplified from individual mites by polymerase chain reaction (PCR) and the amplicons were sequenced directly. A total of 148 ITS-2+ sequences of 404 bp in length were obtained and 67 variable sites were identified (16.59%). UPGMA analyses did not show any geographical or host-specific clustering, and a similar outcome was obtained using population pairwise Fst statistics. These results demonstrated that ITS-2 rDNA does not appear to be suitable for examining genetic diversity among mite populations. © 2008 Elsevier B.V. All rights reserved.