Distribution of the breeding water birds in ponds of Osaka Prefecture.
The distribution of breeding water birds was investigated in 1178 ponds of Osaka Prefecture, from April to August in 2000. Among 45 recorded species, 15 species were bred in the ponds. Little Grebes, Spot-billed Ducks, and Moorhens were the most common breeding birds in the ponds. Ten breeding colonies of herons were also recorded. The breeding of introduced species, Mute Swans and Domestic Ducks, were confirmed.