Block Island Meadow Vole (Microtus pennsylvanicus provectus) a.k.a. Meadow Mouse, Field Mouse Is the Block Island Meadow Vole a species or sub-species? In August 1899, an accomplished New England naturalist, Outram Bangs, visited Block Island for the purpose of surveying for the presence and abundance of mammal species. And, to compare his findings from Block Island to those found throughout southern New England and coastal islands. In the ten days that he was on B.I., Bangs set hundreds of traps around the Island and found that "Mammals were not al all common on the island." Of the four species that he detected (house mouse, deer mouse, rat and meadow vole), Bangs found meadow vole to be the most abundant. In a paper presented in the Proceedings of the New England Zoological Club, Bangs described the physical features of the meadow vole found on Block Island and concluded that it "...appears to be a very well-marked island form of the pennsylvanicus group...", and thus a new species - Microtus provectus. In the 1950s, the scientific community started to reconsider Bangs separate species status for the Block Island Meadow Vole, and alternatively suggested that it is actually a sub-species of Microtus pennsylvanicus (i.e. Microtus pennsylvanicus provectus). This is based on the work of Bernice Wheeler, who demonstrated in the confines of a laboratory setting that some (although not consistent) hybridization between M. pennsylvanicus and M. p. provectus occurred. Further support for the sub-species conclusion was based on work of J. L. Chamberlain, who compared size measurements of Block Island, mainland and Outram Bangs meadow vole specimens. Chamberlain found that although the meadow voles from Block Island were on average slightly larger, there exists considerable overlap among the populations, and the differences, he concluded, were not enough to support separate species status. In 1998, Dr. T. Husband from the University of Rhode Island compared DNA samples from mainland Rhode Island and Block Island meadow voles, in hopes of determining the species status of the Block Island Meadow Vole. Unfortunately the results of that work were found to be inconclusive. Currently, most scientists consider the Block Island Meadow Vole (Microtus pennsylvanicus provectus) to be a subspecies found only on Block Island. However, more research is needed and future DNA studies could identify it as a separate species as described by Outram Bangs in 1908. Meadow Voles (Microtus pennsylvanicus) have: a generally rounded profile and blunt face. bodies that are about 7 inches long. short tails – shorter than the body – about 2 inches. small eyes and small rounded ears. a life span of about 1.5 years. Block Island Meadow Voles (M. p. provectus) are a subspecies of the widely distributed meadow vole found on the mainland. On Block Island, the meadow vole is one of two native terrestrial mammals. (Block Island is home to 6 mammal species - 4 of which have been introduced via human activities.) Although its fur is a little lighter than mainland species, it is generally the same chestnut-brownish tinged with black color; and is always grey below (a slight variation from mainland individuals which tend to have a buffy wash). As is true in other locations, Block Island meadow voles are active day and night, year ‘round, and are an important food source for birds of prey – most especially Barn owls and Marsh hawks (Northern harrier). Meadow voles are very prolific. A female may have between six and seventeen litters a year, producing as many as 100 offspring, and are considered the most productive mammal on earth. For reasons not clearly understood, meadow voles tend to have large population booms every 3 – 4 years. They eat grassy vegetation, flowers, and seeds equal to their own weight each day (roughly 1 oz.). When vegetation is not available – as when there is significant snow cover – meadow voles will eat the bark of shrubs and fruit trees. Unlike mice, meadow voles live and travel above ground in tunnels and chambers, which they make among the grassy windrows, leaf litter and tussocks of meadows, woods and marshy areas. Meadow voles can be found from Alaska, throughout Canada, the northern and eastern United Statesand as far south as South Carolina and Georgia. ( View map ) To learn more about meadow voles and the Block Island Meadow Vole, check out the following resources which were used in preparing this page: National Audubon Field Guide to New England, Peter Alden et al, 1998 Fieldbook of Natural History, E. Laurence Palmer, 1949 Nature in Winter, Donald Stokes, 1976 Notes on the mammals of Block Island, Rhode Island, Outram Bangs, Proceedings of the New England Zoological Club, Vol. IV, March 8, 1908, pg. 19-21 Species Status of the Block Island Field Mouse, Microtus provectus, Bernice Wheeler, Evolution, Vol. 6, No. 1, March 1952, pg. 130 – 131. The Block Island Meadow Mouse, Microtus provectus, J. L. Chamberlain, Journal of Mammalogy, Vol 35. No. 4, November 1954, pg. 587 – 589. http://www.mnh.si.edu/mna/image_info.cfm?species_id=168 View All "Critters of Block Island" Ocean View Foundation Connecting People and Nature