The Bower of Love
Male Birds in Australia Seek to Impress With Flowers and Dancing

Thursday, February 14, 2008

Talk about trying to impress a girlfriend! Satin bowerbirds from Australia go overboard to win a mate.

First, the blue-black male birds build bowers, U-shaped twig "palaces" where the green female birds can stand and admire them.

But a well-made bower is just the start.

Next, the males make a pad of sticks in front of their bowers. Then they decorate their pads with feathers, fruit, flowers -- even bits of plastic. Blue objects are special treasures to satin bowerbirds, but they think red is disgusting.

Home Improvement, Bird-Style

Male bowerbirds know that birds that build the best-looking bowers are more likely to attract females.

"The males want to have the flashiest decorations in front of their bowers," says Gerald Borgia, a University of Maryland professor who studies bowerbirds. "If a bird sees something he wants decorating a neighbor's bower, he tries to steal it. And he fights other males to keep them from stealing his decorations."

During the three-month courting season, the males spend a lot of time poking thin twigs into the sides of their bowers to improve their look. Then they fly off to find even more decorations.

While the males are away, the females start to cruise around. They check out the construction of the bowers and how well they are decorated. They return later to their favorite bowers to see how well the males can dance.

They Dance and Preen

"These birds have very energetic displays," says Borgia. "They puff their feathers and rapidly flap their wings while running sideways in front of their bowers, first to the left and then to the right. During these displays they hold collected treasures in their beaks while facing the female. They also make loud calls and buzzing noises. The most successful males learn how to pick up signals from the females. Some females like noisy, boisterous dancers, while others go for calmer males."

The females don't let on which male they're going to choose. First they go off to build their nests. Then each female returns to the mate of her choice. The favorite males might get picked by 20 or more females. Some might not be chosen at all. Better luck next year!

Meanwhile, the females lay their eggs and then raise the chicks on their own.

Borgia and his students have been studying bowerbirds in Australia for 28 years. Every year they discover new surprises about the birds.

Jason Keagy, one of Borgia's students, spent three years giving intelligence tests to male bowerbirds.

"In one test," he says, "I put red objects under see-through containers in front of each bird's bower. Then I watched how quickly the birds figured out how to remove their containers and get rid of the red objects. I wanted to find out if the smartest guys got the most females. And guess what? They did!"

-- Claire Miller