Growing up going to
football games I noticed a bizarre trend.
The group of fans that
cheered the loudest for their team was considered to be the superior group of
fans. In my family we usually
decided things based on the mantra “I was here first! I was here LOUDER!” with the louder person occasionally being the victor. Little did I realize that we were
simply following the rules of vocal dominance.
The idea of one individual
proving their “superiority” or fitness over another is nothing new, especially
in the animal kingdom. Some
species, such as most hoofed mammals will physically challenge one
another. Others avoid physical
contact due to the high risk of injury and prove their dominance in other
ways. Male lemurs have scent
fights. They rub the tips of their tails with the scent glands that are found
in their wrists and then rub their tail in the other lemur’s face. Humans establish dominance through
material goods…like sports cars.
Vocal dominance however is less about looks or smell, and all about
noise.
We have two species of
birds at the behind the scenes area of World Bird Sanctuary that exhibit vocal
dominance. The Red-legged Seriema
and the Laughing Kookaburra. Both
of these species determine who is the top bird, by whoever can call the longest
and the loudest. This is not so
much fun for their human caretakers when all
three of them are in one building for the winter.
Red-legged Seriemas are found in the grasslands of South
America. They are most famous for
their eating habits, repeatedly slamming their prey (mostly snakes) into the
ground until they are ready to be swallowed whole. However, as anyone at World Bird Sanctuary can tell you,
they have another infamous trait--their call. A Seriema has a coiled trachea which acts as a resonating
chamber making their high pitched call incredibly loud! For many years Sara our breeding female
was the local champion always out-calling the rest. Last year, however, Locust took the lead and with Sara off
in a breeding program, he just might keep it. Just about any loud or high pitched noise will set off the
Seriemas; the phone, the hatchet hitting the cutting board, the parrots, or the
door slamming.
Even Chadder, our laughing
Kookaburra, famous for the children’s song, is laughing not because of how
happy she is, but because there is another bird in her territory. Kookaburras live in small family groups
of about 3-5 and they are big on family feuds. If there is another group of Kooks nearby the whole family will
start calling until one group gives up and concedes the fight. This usually means that once the
Seriemas get going, Chadder follows closely behind. Her hollow bill not only helps with keeping her cool, but it
also amplifies the sound of her call.
She is only a teensy bit quieter than the Seriemas, even though she
weighs only 6 ounces!
Vocal dominance is a way
for some species to declare fitness without risking injury to themselves. Unfortunately we have highly
competitive birds. Just in case
you were wondering, if we humans could ever out call them and claim top billing…let’s
just say it makes them even louder.
Since these birds are cold
sensitive, they are now in their winter quarters behind the scenes. However, when the weather warms up be
sure to visit the World Bird Sanctuary’s exhibit line just beyond the Wildlife
Hospital. You may be lucky enough
to witness a calling competition by these very vocal birds.
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