Nest-tree loss and threats to hornbills and their nesting habitat
More than half of the nest-trees were inactive by the end of the study. There was
loss of nest-trees due to natural causes such as nest hole shrinkage, occupation
by other cavity-dwelling animals and breakage, similar to what Chuailua et al.
(1998) found in Thailand. Five were lost due to cutting of the nest-tree and eight
were abandoned because of human disturbances.
An important finding of this study was that hornbills will nest in logged
forests or even degraded forest, though the nesting attempts are usually hampered by human disturbance and unsuccessful. This suggests that hornbills
would nest successfully in such marginal habitats if further degradation of or
disturbance at the nest-site could be halted. Given the apparent limitation of suitable
nesting trees and that hornbills will nest in marginal habitats, it is necessary
to widen the scope of conservation plans to include the 70% of forests that occur
outside the existing protected area network (national parks and sanctuaries) of
Arunachal Pradesh. Special measures for protection of reserve forest areas from
habitat loss and degradation will go a long way to ensuring the long-term
conservation of hornbills.