Sanctuary Asia, October 2017 77
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Sanctuary Asia, October 2017 77
Characteristically tossing up its bird kill before
catching and swallowing it, this massive male Great Indian
Hornbill looks positively prehistoric. Its earliest Ground
Hornbill Bucorvus brailloni ancestors in Africa roamed the
savannas during the Miocene, some 15 million years ago. A
single femur bone of the B. brailloni unearthed in Morocco
is the only fossil evidence of hornbill ancestors to have ever
been found. Interestingly, studies indicate that hornbills may
have originated much earlier... about 50 million years ago in
the Eocene epoch. Though the evolutionary history of the
hornbills might still be unresolved, their striking and highly
successful evolutionary adaptations – the prominent, large bills
and their ritualistic nest-sealing practices are subjects of both
awe and continual study.
The Great Hornbill, you see here, is symbolic of the dense
old-growth forests comprising large, wet evergreen forest
trees, moist lowland forests and moist deciduous forests
of the Indian subcontinent and Southeast Asia. In fact, the
occurrence of this species in its habitat depends on the
presence of large trees such as those of the Bombax ceiba
and Tetrameles nudifl ora among several others. Unfortunately,
hunting, logging, mining and dam reservoirs continue to pose
a looming threat to the hornbill and the old, large trees it
and several other species depend on. The nesting behaviour
of hornbills is unique. The female seals herself into a large,
naturally-occurring cavity in an old tree, using fruit pulp mixed
with her own faeces to create a tough barrier that prevents
large predators from entering. Once sealed inside, she and her
clutch are entirely dependent on the male to bring them food,
presented to the family through a narrow slit crafted such
that the birds’ bills are able to deliver a variety of morsels over
the next four months! The hornbills symbiotically repay their
host for the shelter by casting seeds far and wide, enabling
the trees to colonise distant areas, thus earning the sobriquet
‘Feathered Foresters’.CASQUED
GIANT
OF OLD GROWTH FORESTS
Location: Valparai, Tamil Nadu
Photographer: Karthik Ramamurthy/Entry–SWPA 2017
Camera: Nikon D7100,Nikkor: 200-500 mm. f/5.6,
Shutter speed: 1/1000 sec., Aperture: f/7.1, ISO: 640, Focal length: 500 mm.
Image taken: March 28, 2016, 10:19 a.m.