Marmota olympus

256. Olympic Marmot Marmota olympus French: Marmotte des Olympic / German: Olympic-Mountains-Murmeltier / Spanish: Marmota de las Olimpicas Taxonomy. Marmota olympus Merriam, 1898, “From Timberline at head of Sole- duc River, Olympic Mountains, [Olympic Nat. Park] Washington [USA].” This species is monotypic. Distribution. Endemic to the Olympic Mts of W Washington (NW USA). Descriptive notes. Head-body 720-750 mm (males) and 670-690 mm (females), tail 210-237 mm (males) and 180-192 mm (females); weight 8.5-11 kg (males), 4.1-4.3 kg after hibernation and 6.7-7.5 kg (females), 2.7-3.5 kg after hibernation. The Olympic Marmot has dorsal pelage of straw yellow-brown to light brown that fades to yellow during summer. Snout is white often, extending to eyes. Venter is usually more rufous or gray than dorsal pelage. Tail is relatively long and densely haired, straw yellow to tan. Chromosomal complement is 2n = 44 and FN = 66. Habitat. Open grass, sedge, and forb subalpine and alpine meadows and talus slopes near and above timberline (most habitat is in the Olympic National Park, USA). Food and Feeding. The Olympic Marmotis an herbivore that feeds on sedges, herbs, roots, grasses and sometimes conifer bark and cambium. Dry grasses may be collected underground for either food or bedding. Foraging by the Olympic Marmot can remove ¢.30% of the biomass and promotes a high level of plant diversity. They will eat animal material when available; cannibalism has been observed. Breeding. The Olympic Marmotlives in multi-burrow colonies where most breeding occurs. Females typically reproduce in alternating years. Litters are 3-5 young, and young remain in natal areas until at least their third year when they disperse. Activity patterns. The Olympic Marmot is diurnal and is only active for 4-5 months each summer and hibernates within burrows for the remaining 7-8 months of the year; spring emergence is in April-May. Movements, Home range and Social organization. Burrows, often with small mounds at the entrance, are common in colonies and are used for maternal nests, sleeping dens, and escape. Sleeping chambers are often lined with dry plant material. Polygynous colonial groups commonly consisting of a single dominate adult male, less than three adult females and numerous two-year olds, one-year-olds, and young-of-the-year. The Olympic Marmot is among the most social of marmots. Colonial territories are 2-8-7 ha. Subordinate males may live on peripheries of colonies but are treated as non-residents. Mortality occurs mostly in winter, especially in years with little insulating snowpack. Scent marking of rocks and plants with oral and cheek glands is common. Four distinct alarm calls are produced in response to potential threats and number of whistles, tooth chatters, growls, “yips,” and “chucks” are used in a variety of contexts. Status and Conservation. Classified as Least Concern on The IUCN Red List. Population trend of the Olympic Marmot is declining. Habitat degradation due to climate change and unusually heavy predation by Coyotes (Canis latrans) and other predators in their highly isolated habitat are major challenges. Bibliography. Armitage (2013a, 2014), Barash (1973, 1989), Blumstein et al. (2001), Edelman (2003), Griffin et al. (2009), Thorington et al. (2012), Witczuk et al. (2013).
Published as part of Don E. Wilson, Thomas E. Lacher, Jr & Russell A. Mittermeier, 2016, Sciuridae, pp. 648-837 in Handbook of the Mammals of the World – Volume 6 Lagomorphs and Rodents I, Barcelona :Lynx Edicions on page 822, DOI: 10.5281/zenodo.6840226