Breeding-ground habitat conditions and the survival of mallards

The relationship between habitat conditions in prairie breeding areas of North America and mallard (Anas platyrhynchos) survival rates was investigated. Annual survival-rate estimates for mallards generally were higher during years of high May pond numbers and low mallards-per-pond ratios than during years of low pond numbers and high ratios. This tendency was most pronounced among males. These results suggest that mallard survival probabilities may be affected by breeding-ground habitat conditions.