Second North American Sea Duck Conference - Patuxent Wildlife ...

SECOND NORTH AMERICAN SEA DUCK CONFERENCE
HABITAT FEATURES ASSOCIATED WITH THE DISTRIBUTION OF
BREEDING PAIRS OF BARROW’S GOLDENEYE
IN EASTERN CANADA
Bruno Drolet, Michel Robert, and Jean-Pierre L. Savard
Canadian Wildlife Service, Environment Canada, 1141, route de l’Eglise, P.O. Box 10100, Sainte-
Foy, Quebec, Canada G1V 4H5; bruno.drolet@ec.gc.ca
In 2000, the eastern North American population of Barrow’s goldeneye (Bucephala islandica) was
listed as being “of Special Concern” by the Committee on the Status of Endangered Wildlife in
Canada, and is now on the Canadian List of Wildlife Species at Risk under the Species at Risk Act.
This small population, estimated at about 1,200 pairs, faces a number of threats on its wintering
and breeding grounds: maritime shipping and oil spills, contamination, and breeding habitat loss
via forest exploitation. In 2001, we air-surveyed 412 lakes in a drainage basin located in the core
breeding area of the eastern North American population of this species. Using logistic regressions,
we examined relationships between the occurrence of Barrow’s goldeneye and 20 biotic and abiotic
habitat attributes determined at various scales. This species was associated with fishless lakes, lake
altitude and the mean slope of the surrounding landscape (500m radius). The model performed better
in the determination of absence in low potential areas (low altitude lakes) than of presence in high
potential areas (high altitude lakes). This could be due to low breeding densities in optimal areas
and the associated difficulty of establishing strong habitat relationships for a species at risk that is
physically unable to occupy all suitable habitats. At the landscape scale, lakes used by Barrow’s
goldeneye (over 600 m in altitude) formed large patches that could be predicted by the proposed
logistic model. Considering the importance of determining potential breeding habitats for this species
in order to implement adapted forest management practices, the accuracy of the model will be tested
in 2005. Survey data from 600 lakes distributed across the entire breeding range will be used. The
results of this study will be presented.
16 ANNAPOLIS, MARYLAND, USA NOV. 7-11, 2005