1. Influence of fish on waterfowl and lakes;ANDERSSON;Anser,1981
2. Food of ducklings of surface feeding ducks at Lake Myvatn, Iceland;BENGTSON;Ornis Fenn,1975
3. Interactions among coexisting predators-a field experiment with dragonfly larvae;BENKE;J. Anim. Ecol.,1978
4. Food availability and preferences of juvenile Mallards;CHURA;Trans. 26th N. Am. Wildl. Conf.,1961
5. Harmonic mean measure of animal activity;DIXON;Ecology,1980