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Murray M. Gillespie

Publications and source records attributed to Murray M. Gillespie.

2 recordsLinked to original sources

Fall and winter distribution of Canada geese in the Mississippi flyway

Canada geese ( Branta canadensis ) from northern Manitoba and northern Ontario were marked with leg bands and neck bands and observed throughout the Mississippi flyway from 1978 to 1989. We used observations of neck-banded geese within each state to determine the relative fall/winter distribution of the Eastern Prairie Population (EPP) and the Mississippi Valley Population (MVP). Mississippi Valley geese were affiliated with states east of the Mississippi River; EPP geese were affiliated with states west of the Mississippi River. However, we found geographic differences in population distribution within several states. Significant annual changes in distribution also occurred in most states. Management of Mississippi flyway geese should consider the differences in both population dynamics and spatial and temporal distributions of MVP and EPP geese in determining state and flyway harvest objectives.

Journal of Wildlife Management

Lead exposure in Canada geese of the eastern prairie population

We monitored lead exposure in Eastern Prairie Population Canada geese during summer-winter, 1986-1987 and 1987-1988 at 5 areas. Blood lead concentrations in geese trapped during summer at Cape Churchill Manitoba were below levels indicative of recent lead exposure (0.18 ppm). Geese exposed to lead (&ge;0.18 ppm blood lead) increased to 7.6% at Oak Hammock Wildlife Management Area (WMA), southern Manitoba, where lead shot was still in use, and to 10.0% at Roseau River WMA, northern Minnesota, when fall-staging geese were close to a source of lead shot in Manitoba. Proportion of birds exposed to lead dropped to <2% at Lac Qui Parle WMA, Minnesota, a steel shot zone since 1980. On the wintering grounds at Swan Lake National Wildlife Refuge in Missouri, 4.9% of all geese showed exposure to lead before the hunting season. Lead exposure rose to 10.0% after hunting ended and then decreased to 5.2% in late winter. Incidence of lead shot in gizzards and concentrations of lead in livers supported blood assay data. Soil samples indicated that lead shot continues to be available to geese at Swan Lake, even though the area was established as a non-toxic shot zone in 1978. Steel shot zones have reduced lead exposure in the Eastern Prairie Population, but lead shot persists in the environment and continues to account for lead exposure and mortality in Eastern Prairie Population Canada geese.

Minnesota, Manitoba