Saturday, January 25, 2014

Prepare For Vocal Domination

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.

Two young bull elk sparring to establish dominance (photo by Gay Schroer)
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.
Sara and Gomez, two of our Red-legged Seriemas calling in unison (photo by Gay Schroer)
 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 though Chadder our Laughing Kookaburra  is small, her call is mighty (photo by Gay Schroer)

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.

Submitted by Leah Tyndall, World Bird Sanctuary Naturalist/Trainer

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