Potoos
are a group of seven species of tree-dwelling birds native to the Neotropics of
Central and South America. They are not
much to look at and you’ll struggle to see them at all! They are not brightly colored like many tropical
birds or fierce like raptors, but they are masters of disguise. Their complex
feather patterns of grays, browns, and black resemble tree bark perfectly. They can stand perfectly camouflaged atop a
dead tree branch. A potoo will position
itself to mimic an extension of the tree branch itself.
A Common Potoo camouflaged on a stump (wikipedia.org)
They are
nocturnal and spend the day resting, out in the open on the end of a dead tree
limb. They have unusual slits in their
eyelids which allow them to sense movement even when their eyes are closed. The instant a potoo detects an intruder it slowly
moves its head straight up and freezes.
With its beak pointing up to the sky, it stays perfectly still until the
threat passes, looking like no more than the end of a broken branch. They can move their heads unperceptively slow
in order to watch a predator carefully.
They will squint their eyes as to not expose themselves by revealing too
much of their bright yellow irises.
These birds are so amazing at camouflage that they show complete composure
under pressure and only break free from their disguise if a predator is almost
upon them.
A Long-tailed Potoo (wikipedia.org)
The Rufous
Potoo is the smallest of the seven species and is invisible among dead leaves and
trees. To increase their camouflage even
further, they may rock back and forth while roosting to even closer resemble a
dead leaf that’s waving in the breeze.
Potoos are
very selective nesters. They will not
build a nest, but will find an upright broken tree branch with just enough
depression or crevice for a single egg to rest.
Both parents will take turns shielding the egg from predators and bad
weather. Potoos feed on flying insects at dusk and at night. They will regurgitate partially digested food
to feed the chick. When the chick is too
large to hide under its parent’s protection, it will assume the same freeze
position resembling a clump of fungus, since it has gray downy feathers.
Potoos
have proportionately large heads for their body size and long wings and
tails. The large head is dominated by
enormous eyes and a massive broad bill, helping them to see prey in little
light and to then catch and swallow that prey whole. Beetles and other flying insects are their
main source of food. However, one Northern potoo was found with a small bird in
its stomach!
Fortunately
all seven species of potoos are not on the endangered or threatened species
list, but like all tropical wildlife, they are still subject to rapid loss of
habitat by deforestation.
Submitted by Sara Oliver, Naturalist
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