OBSERVATIONS AT A NEST OF THE CUCKOO-ROLLER LEPTOSOMUS DISCOLOR

A nest-cavity with two nestlings of Leptosomus discolor, found in the Comoro Islands in October 1965, are described. This is apparently the first time that nesting has been observed. The nest was in a natural cavity in a tree growing in light secondary forest. Both nestlings still had traces of their original white down, even though they were nearly fully-feathered. Apart from two thick tufts of white down on the hind-crown, the plumage appeared very like that of the adult male. Fragments of egg-shell were found in the nest. They suggest that the original eggs were rather rounded, of a pale unmarked creamy-buff, slightly glossed, measuring about 46 ± 5 ± 37 ± 5 mm. During six hours observation at the nest the birds made five visits and brought six chameleons (no other food was seen). The female fed the young, but the male accompanied her. She did not enter the nest, except on one occasion. Details of this visit are given in full, being particularly remarkable for the tameness of the female. The threat-display of the young is described and possible predators mentioned. Several calls are described, some apparently for the first time. It seems likely that most prey is caught above ground-level. The evidence suggests that the birds are monogamous, not polyandrous as has been suggested.