Factors Associated with Duck Nest Success
in the Prairie Pothole Region of Canada
Nest Fate
We determined for all of the 5 common species combined in each habitat class of each half-area-year the percentage of unsuccessful nests that failed due to predation, agriculture, and other agents, and the percentage of abandoned nests caused by predation, weather, and other agents; nests abandoned because of investigator activity had been excluded previously. We combined nests of the 5 common species to increase sample size. By doing so, we assumed that all nests in a given habitat were at equal risk to all agents responsible for nest failure. In half-area-years where data on causes of nest failure in a particular habitat class were inadequate, we used an average value for that habitat class calculated from data for all area-years. We determined percentage of nest failures caused by various agents in a half-area-year; rates were weighted by a value equal to the product of habitat preference of each species and availability of habitat in that half-area-year. To obtain an estimate for each area-year, we weighted the rates for each half-area-year by number of pairs of the 5 common species in each half-area and combined them.
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