Comment: "Small" is ambiguous. For details on "Small rivers" (e.g. the Salween river) see http://worldwildlife.org/biomes/small-river-ecosystems. This class will be replaced with a less ambiguous class.
Definition: Type of food comprising the majority
of the diet of an animal.
Attribution: Richard M. Sibly, Christopher C. Witt, Natalie A. Wright, Chris Venditti, Walter Jetz, and James H. Brown. 2012. Energetics, lifestyle, and reproduction in birds. PNAS 109(27):10937-10941, doi:10.1073/pnas.1206512109