Foods of the white-faced heron

A study of the stomach contents of 89 white-faced herons showed them to be primarily wetland-pasture and aquatic feeders. Although predominantly carnivorous, 65 birds had eaten plant material, usually in small amounts. Vegetative parts of sedge, grass and clover occurred most frequently, but in two specimens water-weed comprised the bulk of plant food. Invertebrate food, present in every specimen except one, was predominantly crustaceans, insects, annelids and arachnids. Molluscs and a proportion of smaller invertebrates were considered in most cases to be present as a result of their liberation from gut of digested fish. All birds were collected from habitats where fish especially trout were present or within feeding range. Fish occurred in 45 stomachs. In order of weight consumed they were bully, smelt, trout and whitebait (adult and immature). Elvers and carp were eaten so rarely that they were unimportant in this study.