Social and Behavioral Sciences Commons^™

A Hematologic Survey Of Captive Waterfowl, Hazel Shave, Valeria Howard

USGS Northern Prairie Wildlife Research Center

Hematologic parameters were studied in giant Canada geese (Branta canadensis Maxima), mallard ducks (Anas platyrhynchos platyrhynchos) and various species of diving ducks at seasonal intervals throughout the year. Highest values for packed cell volume, hemoglobin content and erythrocyte counts were found in the winter and pre-nesting periods. Mean corpuscular volume and mean corpuscular hemoglobin varied inversely with these values.

Spring Mortality Of Insectivorous Birds In Southern Manitoba, Jerome R. Serie, Robert E. Jones

USGS Northern Prairie Wildlife Research Center

Migrating passerines frequently encounter adverse weather during their northward movements in early spring. Inclement weather often causes temporary halt of migrating passerines short of their destinations (Curtis 1969). In May 1974, such a grounding of spring migrants occurred in southwestern Manitoba due to unseasonable weather. Many insectivorous birds became weakened or died of starvation as a result of exposure to low temperatures, depletion of fat reserves, and lack of available food.

Arrival of Spring Migrants

The first large influx of insectivorous birds, mainly Myrtle (Dendroica coronado coronata) and Yellow (Dendroica petechia) Warblers, was noted on 19 …