BEACH MEADOW VOLE Microtus breweri (Baird) 



Order: RODENTIA Family: CRICETIDAE 



Distinguishing characteristics : Larger and paler in color than common meadow vole . 



Present distribution : Muskeget Island off Nantucket, Massachusetts. 



Former distribution : Muskeget, including Adams and South Point Islands. 



Status : Apparently persisting on Muskeget; one collected 1956 (Haft) . 



Estimated numbers : Populations fluctuate; apparently at a fairly high level in early 1965. 



Breeding rate in the wild : Several litters (usually five to seven young) annually. 



Reasons for decline : Predation by short-eared owls and by cats kept at Life Saving 

 Station. Habitat eliminated by erosion after storms and by construction. 



Protective measures already taken : Muskeget Island now a refuge for nesting terns. 



Measures proposed : Encourage suitable perennial grass habitat. Continue maintenance 

 of refuge . Elimination of cats . 



Number in captivity : Unknown . 



Breeding potential in captivity : Unknown . 



Remarks : On Muskeget Island, "excessively abundant" in 1869; "only a few" in 1890; 

 "no trace" of them in 1891; a "thriving colony" in 1892; "entirely disappeared" in 1893, 

 when G. S. Miller transplanted a few from nearby South Point Island. Apparently the 

 population underwent violent fluctuations , as do meadow voles on the mainland . This 

 species is especially adapted for digging in sand. 



References : 



Allen, G. M. 1942. Extinct and vanishing mammals of the Western Hemisphere. 



American Committee for International Wildlife Protection. Special Publ . 11, 



pp. 93-96. 

 Haft, J. S. 1963'. Malformations of molars in Microtus breweri . Jour. Mamm., 



44:270-272. 

 Hall , E . R . , and K . R . Kelson . 1959 . The mammals of North America . 



Ronald Press , N . Y . , Vol . 2 , p . 728 . 

 Matthiessen, P. 1959. Wildlife in America . Viking, N.Y.; pp. 130-132. 

 Miller, G. S., Jr. 1896.' The beach mouse of Muskegat Island. Proc. Boston 



Soc. Nat. Hist. , 27:75-87. 



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