First nest description, breeding behaviour and distribution of the Madagascar Serpent-Eagle Eutriorchis astur

The critically endangered, endemic Madagascar Serpent-Eagle Eutriochis astu r was searched for and studied from 1993-98 on Masoala Peninsula, northeast ern Madagascar. Fifteen individual serpent-eagles were detected at nine dif ferent localities throughout the Masoala Peninsula. The first nest of the M adagascar Serpent-Eagle was discovered on 7 November 1997. The nest was in an epiphytic fern Asplenium nidus supported by vines and branches, 20.1 m a bove the ground in a Potameia capuroni of 36.2 cm diameter at breast height . The epiphytic fern was lined with leaves in the centre and twigs were pos itioned to form a nest rim. The nest measured 76 x 57 cm and contained one white egg. The female and male incubated for 77% and 21% of 118 hours of ne st observations, respectively. The egg hatched on 21 November 1997, and the young fledged 62 days later on 22 January. Chameleons Furcifer and Calumma spp., and leaf-tailed geckos Uroplatus sp., made up the most numerous prey types taken, representing 83% of the 133 identified prey. Currently, the M asoala Peninsula forest contains the greatest number of sightings and known density of serpent-eagles in Madagascar.