Tuesday, March 17, 2015

Birdy went a Courtin’

February may be the shortest month, but it is one of the busiest.  Not only is it Black History Month, but it is also the month of Mardi Gras and Valentine’s Day. Valentine’s Day is famous for flower and candy giving as a sign of love and courtship.  Our birds don’t give each other candy, but that doesn’t mean there isn’t plenty of courtship happening.

A "nest" built by Osiris, an Egyptian Vulture (photo: Leah Tyndall)

Birds court one another in a variety of different ways.  Some species sing to one another, others such as Bower Birds, will build a spectacular display in an effort to attract a mate.  Certain species of fowl will have entire breeding grounds called leks dedicated to courtship.  Male Prairie Chickens will display simultaneously while females choose the male with the best display.

Eagles have some of the most spectacular and heart-stopping displays.  Bald Eagles do what is called a talon lock; two individuals lock talons in mid-air and spiral towards the ground before separating and landing on separate perches.  This is repeated over and over.

Bateleur Eagles perform heart-stopping in-flight displays (photo: Leah Tyndall)

Bateleur Eagles have some of the most elaborate of courtship flights.  They will do spins, tumbles and barrel rolls in midair.  While the male is performing these aerial acrobatics the female flies upside down to determine which male she will choose as a mate.  In comparison human courtship seems a little dull, doesn’t it?

Birds are not strictly monogamous either; polygamy is an excellent way to ensure many offspring and that those offspring are well cared for and protected.   Harris’ Hawks for example are polyandrous meaning a female may have two or in extreme cases three male mates to help her care for her young.  Polygamy is one male with multiple females, such as a rooster with his harem of hens.  Other species like Bald eagles will mate for life, only taking another mate if the first one has died.

You might think that our captive-raised or captive for medical reasons birds would not be able to express their feelings as well as their wild counterparts, but you would be mistaken.  They may not be able to perform elaborate flights, but there are still displays occurring. The male owls make depressions in the ground called scrapes; and stand in these hooting.  The male owls will set aside around half of their food for their “mates”.  Niles, a Southern Ground Hornbill, would parade around with food in his beak to show off his hunting skills to his keepers.  Some of the male hawks will collect sticks and feathers to build nests for their loved ones.
Wagner, a Red-tailed Hawk, building his nest (photo: Leah Tyndall)
Even our birds on equipment will use their leashes to form the outline of a nest, placing them very deliberately on the ground.  Unfortunately whenever they move the nest goes with them.  To ease their frustration we provide them with small sticks and toys that are not quite so mobile.
Sanibel's nest (photo: Leah Tyndall)

Males are not the only ones busy during breeding season.  The female owls begin incubating their toys and sometimes their food.  Osiris a female Egyptian Vulture builds an elaborate nest and will even line it with fur and feathers.  Sanibel a Bald Eagle once made a mud nest so that she could lay an egg, which was not fertile.  Jersey the Barred Owl has developed a brood patch in years past.  This is an area on her belly free of feathers that aids in the incubating of eggs.  The female African Pied Crows will bow and swirl their tales.

Gomez, a male Seriema, proudly offering a lizard to the photographer (photo: Gay Schroer)

Male or female, many birds over the years have tried to court their trainers, even going so far as to try and, ahem, “seal the deal.”  This can be a little awkward, but is to be expected from imprinted birds.  They do not know they are what they are, instead thinking that they are humans or that humans are birds.  That means come breeding season, they do not look for their species for a mate.  They look for ours!

Birds have a variety of different methods for courtship as well as different types of bonds.  These could be pair bonds, harems, or multiple mates all with different advantages and disadvantages.  Even birds in captivity have adapted different methods so that they too can attract a mate; even if that potential mate turns out to be a different species.

If you are hardy enough to brave the cold weather in February and March take a walk down the exhibit line at the World Bird Sanctuary.  You may see some of our birds exhibiting some of the above-mentioned courting behaviors.

Submitted by Leah Tyndall, World Bird Sanctuary Naturalist/Trainer

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