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Series

1981

Biological Sciences Faculty Publications

University of Montana

Articles 1 - 2 of 2

Full-Text Articles in Life Sciences

Seasonal Variation In The Foraging Behavior Of Some Migratory Western Wood Warblers, Richard L. Hutto Oct 1981

Seasonal Variation In The Foraging Behavior Of Some Migratory Western Wood Warblers, Richard L. Hutto

Biological Sciences Faculty Publications

I observed the foraging behavior of four warbler species (Dendroica petechia, Oporornis tolmiei, Geothlypis trichas, and Wilsonia pusilla) in the summer in Wyoming and in the winter in Nayarit, Mexico. Of six variables (absolute foraging height, relative foraging height, vegetation density, horizontal foraging position, feeding method, and foraging substrate) believed to be potentially important in distinguishing the warbler species ecologically, the two foragingheight variables provided the greatest separation of the four species in both summer and winter. An analysis of the behavioral similarity of each species from summer to winter revealed that feeding method was the least …


Larval Specialization And Phenotypic Variation In Arctopsyche-Grandis (Trichoptera, Hydropsychidae), F. Richard Hauer, Jack Arthur Stanford Jan 1981

Larval Specialization And Phenotypic Variation In Arctopsyche-Grandis (Trichoptera, Hydropsychidae), F. Richard Hauer, Jack Arthur Stanford

Biological Sciences Faculty Publications

Life history, trophic dynamics, abundance, and microdistribution of Arctopsyche grandis (Banks) were investigated in the Flathead River Basin, Montana. Two morphologically and ecological distinct larvae (Type I, with a head stripe and Type II, without a head stripe) were found throughout the drainage except in lower order streams. Type II larvae grew more rapidly and attained a larger size in final instar than Type I larvae. In areas where A. grandis biomass was greatest, Type I larvae were >10 times as abundant as Type II larvae. Type II larvae selected microhabitats characterized by larger interstitial spaces; Type I larvae were …