When it comes to sex, birds don't mess around

Six seconds. When you think of all the energy birds invest in courtship displays and protecting their territories, six seconds isn't very long.

When it comes to sex, however, birds don't waste time.

Take the female killdeer I was watching in a prairie on the Sherburne National Wildlife Refuge a few weeks ago. She seemed to be minding her foraging business, walking this way and that, occasionally picking at the ground.

Suddenly, there were two birds. They quickly approached each other. Then the male hopped up and stood atop the hen's back.

Some birds manage the mating maneuver with the female perched in a tree or bush, the male aflutter over her. Killdeer, though, remain aground, with a little teetering and wing flaps to maintain balance.

Each bird cranks his or her tail sharply to one side. This allows the male to place his cloacal opening and what bird biology books refer to as his "protuberance" against her cloaca for transfer of sperm. (The cloaca is the bird's all-purpose vent.)

This need be done only once to provide sperm for fertilization of all eggs the female will lay for the coming brood.

Walk on the wild side

The wildlife refuge was an exciting place that day. On the far side of the prairie, I took a half-mile path that includes a boardwalk over a small cattail marsh. My footsteps on the boardwalk provoked a mighty scolding from a sedge wren. In defense of his nesting territory, he was tolerating intruders of no size or shape.

It wasn't long after my encounter with the wren that I came upon a pair of sandhill cranes. Their cries of concern about my presence mixed with the hops and jumps of crane foreplay. They seemed uncertain of priorities.

Mrs. Killdeer, on the other hand, was not. After mating, she probably found a patch of gravel, where she would scratch a small depression to serve as a nest. When her chicks hatch, they'll be up and running as soon as they're dry. I hate to sound partial, but they're about as cute as birds get.

If you take a walk on a prairie path this summer, you're likely to see birds. If not killdeer, something else interesting will be there. But you'll probably have to wait until next spring to see the acrobatics of mating.