Owl's Beak or Bill
All Owls have a short, curved, downward-facing beak
that is hooked at the end. It is designed
specifically for gripping and tearing prey. The crushing power of the
bill is usually used to kill prey once captured.
The upper edge of the
lower bill and the lower edge of the upper bill taper to a sharp edge, and
overlap in a scissor-like fashion, enabling it to cut through the tissue of
the prey.
Cross-section of an Owl's bill
The bill is curved downwards in
order to keep the Owl's field of vision clear. The nostrils are positioned
towards the base of the beak, in a region called the cere. Most Owls
have a very poor sense of smell.
The exposed tips of the bill have
a hard, horny surface for protection. The
lower bill is hinged and does most of the work, although the back of the
upper bill (where it joins the skull) has a narrow strip of flexible tissue
that acts as a hinge, allowing the beak to swivel slightly upwards. Other
birds also possess this, and it is possible that its purpose is some kind of
visual communication.
Some species of Owls are able to
reduce their body temperature in hot weather by "panting" through partially
opened bills. This is called "gular fluttering" - gular having to do with the
throat area. Warm air is exchanged ambient
air which is drawn into the highly vascular throat where the blood
vessels are constricted, thus enabling heat dispersion.
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