Sulawesi knobbed hornbill. Photo by Rhett Butler (2011).
The knobbed hornbill (Aceros cassidix) is found on Sulawesi and surrounding islands.
Like other Indonesian hornbill species, the knobbed hornbill feeds primarily on fruit in its rainforest home.
Hornbills form monogamous pairs. When it comes time to nest, a pair will choose a hollow or cavity in a large tree. The female enters and, with the help of the male, proceeds to seal the entrance of the hollow, leaving only a small hole. The male delivers food while she is nesting and rearing the young.
While the knobbed hornbill can be difficult to see (but easy to hear — its wing beats sound like a helicopter) in the forest due to vegetation in the canopy where it perches and feeds, is not considered endangered.
More pictures of hornbills.