212 C. S. Wehh—Notes on a Collecting Trip to N.E. Tanganyika


One of the most conspicuous birds in this region is the Silvery-

cheeked Hornbill (Bycanistes cristatus), a large species which is

quite plentiful and can be seen at most times in a large flock.

Much has been written about the extraordinary nesting habits of

Hornbills, but many interesting details concerning the nesting

period have only recently been discovered. With the Silvery-

cheeked Hornbill (as with other species) the female is sealed in

a cavity in a tree with a muddy substance which sets hard, a slit

being left through which the male bird feeds his mate. Recent

observations have shown that she remains penned up in this prison

for over four months, during which period the eggs are hatched

and the young birds become fully fledged, the male bird feeding

the whole family. Even when this stage is reached, it is the male

which re-opens the cavity and liberates the inmates. It is

interesting to note that this is not done until the young are

capable of flying strongly. Why this method should be adopted

by such large birds with powerful bills, well able to deal with

any natural enemies capable of reaching the nesting site, it is

difficult to say, but it evidently works very well judging by the

numbers of Hornbills in existence. It is not easy to suggest the

origin of such a habit; perhaps one of the original Hornbills

had a faithless wife or one who could not be bothered with the

monotonous duty of hatching eggs and he settled the problem by

shutting her up. Anyway nowadays the female is in such a state

of subjection that she stays where she is put and in this respect it

seems that Bycanistes cristatus has succeeded where Homo sapiens

has failed. I feel sure that this instinct in the Hornbill is so

strong that if anything happened to the male, the female would

starve to death on the nest instead of liberating herself.


If these birds breed annually as is believed, the poor hen

must spend a third of her existence in a sort of prison with hardly

room to move. What would happen to the man who treated birds

like this in captivity? And yet nature has given her approval

of such methods.


These birds when not nesting, return nightly to the same

communal roosting place and may be seen crossing the valleys at



