Melissa Skyer


River otters were re-introduced to Western New York by the Department of Environmental Conservation between 1995 and 2000. The success of this population relies heavily on the availability of suitable prey. Diet was investigated via frequency of prey occurence in scats from 2004-2006. Overall diet was comprised mostly of fish and crayfish. The major fish taxa were Centrarchidae (sunfish), Cyprinidae (carp), and Salmonidae (trout); less common were Esocidae (pike and Castostomidae (sucker). All fish species combined ocurred at 100% frequency during the winter and spring months, but declined during the summer and fall. Sunfish prey were at their highest frequency in the winter and spring months (50-60%), and tapered off to 10-20% in the summer and fall. Carp in the diet showed a seasonal trend, highest in the spring at 30%, 10-20% during the summer and winter, and <10% in the fall. Trout occurred in the diet mostly in the spring (<20%) and was low in frequency for the rest of the year. Crayfish consumption displayed an inverse seasonal relationship to fish, and was highest in the summer (80%) and fall (60%) but was rare in winter and spring. Minor prey items (less than 5% of the diet) were insects, mice, a bird, and a freshwater mussel. Vegetation occurred in scats with other prey types at a frequency of 28.8%. Vegetation in the diet dominated in the fall at 60% and spring at 20%, with no occurrences in the winter and summer months. The food habits of this reintroduced population closely resemble those of other studies on both Lontra canadensis and Lutra lutra, suggesting that prey resources are adequate in type and abundance to support river otter dietary needs in Western New York.

Library of Congress Subject Headings

North American river otter--New York (State)--Food.; Predation (Biology)

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Thomas H. Gosnell School of Life Sciences (COS)


Stelle, Lei Lani - Chair


Note: imported from RIT’s Digital Media Library running on DSpace to RIT Scholar Works. Physical copy available through RIT's The Wallace Library at: QL737.C25 S59 2006


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