Seasonal changes in the diet, body weight and condition of fledged Mallard (Anas platyrhynchos platyrhynchos L.) in eastern England.

Abstract

There is very little published information on the summer food of the Mallard (Anas p. platyrhynchos L.). Previous work on the food of this species in England has been largely confined to the open season, i.e. from the 1st September to the 31st  January; (e.g. Olney 1963, 1965, 1967). Olney (1967) does however indicate that the proportion of animal foods taken increases in the summer months. Recent work in the United States (Swanson and Meyer, 1973) has shown that foods of animal origin are important to several species of breeding waterfowl though Mallard in this case were not studied. Bartonek (1972) however, found that 87 ± 35 % of the oesophageal contents of fledged juvenile Mallard as animal material.

This paper describes the food, body weight and condition of fledged Mallard, collected over two seasons as part of the Amey Roadstone - Game Conservancy wildfowl research project which was established in January 1972.