Madagascan pochard of numerous fish species in the lake that killed most of the pochard chicks and damaged nesting sites. Adult birds are also likely to have become victims of introduced fishes. Rice cultivation, cattle grazing on the shores, burning of shore vegetation, introduced mammals (rats), gill-net fishing and hunting are all factors that led to the duck's disappearance from the lake. The last record of multiple birds at Lake Alaotra is from 9 June 1960 when a small flock of about 20 birds was spotted on the lake. Despite the rarity of the species in 1960, a male was shot, and
What Bird is That? kookaburra seated on and within a large red question mark. It contains 36 coloured plates of paintings of Australian birds by the author, as well as several black-and-white photographic plates of habitat. There were numerous reprints and revised editions in various formats produced well into the 1980s. The first edition was sponsored by the Gould League of Bird Lovers of New South Wales of which Cayley was a Council member. In return for its sponsorship, Cayley offered the Gould League four tenths of his 10% book royalty. However, initial sales were slow and in 1935 he sold his entire share