Helmet Vanga Euryceros prevostii is one of a handful of Malagasy endemic birds considered to be restricted to lowland and lower montane rainforests of north-east Madagascar. Until recently, its best-known haunts were Marojejy Strict Nature Reserve and the Masoala Peninsula, but visiting Marojejy was forbidden without special permission and exploring unprotected, roadless Masoala constituted quite an expedition. This meant that this most astonishing bird went unseen by most birdwatchers visiting Madagascar.
Things have changed. Both Marojejy and Masoala are now National Parks, and permits are easily available, making visits much easier than they were before. It was at Marojejy that Nick Garbutt discovered the nest where he took the wonderful photographs reproduced here. A further development has been the discovery in the I990s of nesting Helmet Vangas in Mantadia National Park, close to Perinet and only a few hours drive from Antananarivo; the species has long been known from this region but very rarely seen until recently.
Why do Helmet Vangas possess such uniquely arched and coloured bills? They are birds of primary rainforest, often joining mixed-species flocks containing other large vangas, but few life history details are known. They mainly eat large insects, but of 98 food items brought to young in a nest on Masoala, 14 were snails, five lizards, five spiders and two crabs. Many items are caught by sally-gleaning (F. Hawkins pers. comm.). It is difficult to imagine how such a diet and foraging technique could account for the most striking bill, as many passerines with (as far as we know) similar diets, such as cuckoo-shrikes, shrikes and probably other vangas, manage with something much smaller. This question, therefore, remains unanswered, but the answer might perhaps be sought in the species' breeding behaviour.
- Graetz, J. 1991. Nest observations of the Helmet Vanga Euryceros prevostii. Newsletter of the Working Group on Madagascar Birds 1: 2.
- Powzyk, J. 1995. Exceptional observations in Mantadia National Park. Newsletter of the Working Group on Madagascar Birds 5 (2): 4.
Royal Holloway Institute for Environmental Research, Huntersdale, Callow Hill, Virginia Water, Surrey GU25 4LN, UK.