Hirundo rustica

I debated about using this one as the blip today because there's a number of things I'm not happy about in terms of quality. I decided in its favor in the name of the moment, which I like a lot.

These two are Barn Swallows (or, as I understand them to be in Europe, simply Swallows), the most widespread species of swallow on the planet. I've been noticing them returning these past couple weeks, and I found them today building nests under a bridge at Don Edwards NWR in Fremont.

Their coloring is similar to that of two other North American swallow species, the Cave and the Cliff, though the Barn Swallow is the only one with a heavily forked tail. It is thought that males with longer forks have better reproductive success, as length is an indication of genetic health to prospective mates. The males typically arrive ahead of the females in migration to build a nest, which they advertise when courting females. Because Barn Swallows favor human structures like bridges and overhanging roofs for their nesting sites, they have fared well in the onset of civilization.

There are 6 subspecies of Barn Swallow worldwide. The North American race, Hirundo rustica erythrogaster, is known to travel impressive distances during migration, with some flying to as far as Argentina in the winter.