64 research outputs found
A nesting study of the Black-throated Green Warbler Dendroica virens virens (Gmelin).
http://deepblue.lib.umich.edu/bitstream/2027.42/51683/1/109.pd
Ecological Studies on the Alaskan Arctic Slope
Considers the tundra, or terrestrial environment and animal ecology primarily, citing the prime role of the Naval Arctic Research Lab at Barrow since 1947, in making the North Arctic Slope and adjacent waters one of the best-known sectors of the Arctic. The International Biological Program includes analysis of ecosystems and human adaptability, which demand study in the Arctic, where tundra, a low temperature extreme among ecosystem-types on the land, has a special importance. Future work will require ecologists, physiologists, taxonomists, climatologists, geomorphologists, pediologists and others to understand the tundra habitat and its populations as a total system. The complexity is illustrated by a flow diagram for energy and nutrients in tundra ecosystems and of the energy cycle in the biosphere, with comments on specific problems. Little is known about decomposition processes or life cycles of insects upon which birds feed; more quantitative observation and measurement of vegetation, the base of the food web, is needed. Factors and strategies which influence diversity of animal species in the tundra are discussed. Need to deal with ecology of the normal tundra is crucial, for with discovery of oil in northern Alaska, there is a need to deal with a damaged tundra
Efficiency of Winter Scavengers in the Arctic
Frozen carcasses of brown lemmings, Lemmus trimucronatus, were systematically placed under the snow in various tundra habitats in the fall of 1961 (188), 1962 (201) and 1963 (205) near Barrow, Alaska. Only 8 carcasses were recovered in the following springs. Removal of the carcasses is attributed to: arctic fox (Alopex lagopus) and red fox (Vulpes fulva); brown lemming; the least weasel (Mustela rixosa). Observations of behaviour, systematic trapping and examination of scats were used to suggest the relative importance of these consumers of lemming carrion in the order given above. The inability of investigators of lemming population cycles to find the carcasses of lemmings that die during the winter months is explained by the unusual efficiency of these species in locating and using frozen carrion during the winter months
The Transverse Volcanic Biotic Province of Central Mexico and Its Relationships to Adjacent Provinces Robert T. Moore
The Flowering Plants and Ferns of Mount Diablo, California by Mary L. Bowerman
Volume: 7Start Page: 255End Page: 25
Nature Sanctuaries in the United States and Canada, a Preliminary Inventory S. Charles Kendeigh
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