Tuesday, April 18, 2006

Experimental Design

The barn swallows are back. Mr. and Mrs. B. Swallow, to be precise. This is the 5th year that a pair of the small orange-throated birds with deeply forked tails has chosen our front entryway to build a nest and raise a family. I like to think it's the same pair each year, but unless you happen to be a barn swallow, it's pretty hard to tell.

They show up one fine day in April and sit on the eaves for several days, considering the situation. Any new cats? No. Bird bath still in the garden and operational? Yep. Pesky humans still going in and out their front door? Yes, but we can tolerate them. OK, then. Build the nest!

They have chosen the same section of brick wall, 2 stories up and just under the roof for the past 4 years. The mud-and-straw nest takes them only a couple of days to complete, then mama moves in and papa takes up his post on the rain gutter, ready to swoop outward from the house, drawing attention away from the nest every time one of those humans goes through the door. His attention never wavers. Would that every mother of babies had such an attentive mate.

Honestly, I'm surprised to see them back. Two nests in the past 4 years have fallen down before the family was finished living there. One year, the chicks were nearly grown, and took Father's place on the gutter, clamoring shrilly to Mama and Dad to "Get that new nest FINISHED!". A new nest was completed in record time, and the family moved back in. Unfortunately, the babies in another year weren't so lucky; the nest plummeted to the ground long before the babies were self-sufficient and the parents had an agonizing 48 hours trying to protect their fallen chicks until they all were dead. The parents never built a second nest, but stayed disconsolately around their barren nursery for a few more weeks until their usual time of migration.

But here they are, and this year they have a new idea. Whether by actual design or by chance, this year's nest is different. All of the past nests have been semi-circular; a quarter of a solid oval cemented to the flat face of the wall. Not this year. Now, they have a quarter-circle design going; rather, an eighth of the oval solid. It's snugged up in the corner, with two walls supporting it. More brick wall, less mud and straw. Perhaps the birds have been reading up on the 3 Little Pigs and house building techniques over the winter.

I'm eagerly awaiting the results of their new design.

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