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We investigated predation by nonnative coyotes (Canis latrans) on endemic Olympic marmots (Marmota olympus) in Olympic National Park, Washington, in 2005 and 2006. Although nearly the entire marmot range is protected within the park, declines and local extirpations of the species have been documented. Through analyses of carnivore scat across the range of the Olympic marmot we determined the distribution and relative density of coyotes and characterized the extent to which coyotes and native carnivores preyed on marmots. We used mitochondrial DNA analysis of scats to determine carnivore species, and microsatellite markers for individual coyote identification. Scat analysis indicated that invasive coyotes are widespread and the numerically dominant carnivore on sampled trails within the Olympic highlands-71% (301 of 426) of all scats verified to species arose from coyote. Out of all carnivore scats collected, 11.6% (111 of 958) contained marmot remains. For 85% of the samples with marmots, coyotes were confirmed as the predator. The remainder arose from bobcat (13%) and cougar (2%). Coyotes were the predominant marmot predator across all months and in most regions of the park. Twelve out of 13 coyote individuals identified with genetic markers preyed on marmots. Marmots ranked 5th in frequency of coyote diet items, after snowshoe hares (Lepus americanus), mountain beavers (Aplodontia rufa), voles, and cervids. Scat analysis indicated that in the Olympic Mountains, the coyote as an invasive generalist predator is subsidized by abundant multiple prey, and appears to be the primary terrestrial predator on the endemic Olympic marmot. We conclude that predation by coyotes on marmots is widespread and substantial across the marmot's species range, and therefore likely driving observed marmot declines and extinctions. [ABSTRACT FROM AUTHOR]

We reinvestigated the phylogeny of all 15 species of Marmota to resolve a conflict between 2 published analyses, one by Kruckenhauser et al. and another by Steppan et al., regarding the Olympic marmot (M. olympus) and to improve resolution in the genus. We acquired fresh samples of M. olympus, combined all available data on mitochondrial DNA (cytochrome b [Cytb] and ND3/ND4), new sequences for ND3/ND4, and 2,000 base pairs (bp) of the nuclear RAG1 gene. All analyses indicate that M. olympus is a much older, rather than more recent, offshoot of the widespread hoary marmot (M. caligata) or Vancouver Island marmot (M. vancouverensis). The mitochondrial data and some RAG1 results are largely congruent, but RAG1 differs on several points, including: the subgenus Marmota appears paraphyletic to Petromarmota, with reciprocally monophyletic Palearctic and Nearctic clades; and the long-tailed marmot (M. caudata) and Menzbier's marmot (M. menzbieri) are not sister species, suggesting mitochondrial introgression. Asia was colonized by Marmota from North America at approximately 4.6 million years ago (mya), followed by rapid diversification of several major lineages. M. olympus diverged from the M. caligata--M. vancouverensis lineage at approximately 2.6 mya, whereas M. vancouverensis and M. caligata diverged at only about 0.4--1.2 mya. M. olympus might have survived in isolation on the Olympic Peninsula in a nunatak refugium throughout a series of glacial maxima. [ABSTRACT FROM AUTHOR]

Olympic marmots (Marmota olympus) are large, burrowing rodents inhabiting scattered subalpine meadows on the Olympic Peninsula, Washington. Recently, the population has declined and become increasingly fragmented. The ability of Olympic marmots to recolonize abandoned habitat and to maintain gene flow among extant populations will depend on the number and success of dispersers and the distances that they travel. We monitored 84 radiotagged Olympic marmots to determine dispersal rates, distances, and success. Contrary to previous observations, 3-year-olds were most likely to disperse, although some 2-year-olds and even some older animals, particularly males, moved as well. Of marmots known to be still on their natal home range in the spring of a given year, 16% of 2-year-old males, 50% of 3-year-old males, 17% of 2-year-old females, and 29% of 3-year-old females subsequently dispersed. Dispersal rates for 3-year-olds were slightly lower when all animals were included in the analysis regardless of whether their dispersal history was known. Males dispersed farther than females (median = 984 m, n = 14 versus median = 267 m, n = 13) and 69% of females settled within 500 m of their original home range. If the observed dispersal patterns are representative of range-wide patterns and if Olympic marmot densities remain low, successful dispersal may be too infrequent to sustain reliable recolonization of vacant habitats or even genetic or demographic rescue of isolated marmot groups. [ABSTRACT FROM AUTHOR]