Yesterday we drove down to Haines looking for swallows.  We found just two dozen down at Delepierre’s corner.  Here at our house there is one pair left.  They have three babies in the nest in the corner above our south door.  It will take another two weeks for them to get those babies big enough to leave the nest.  I imagine that all of the remaining swallows are similarly raising late broods, and could not leave with the flock.

Several days ago there were hundreds of swallows in half a dozen flocks between here and Haines.  There were over a thousand individuals.  They perched in long, almost-countable lines on the power lines.  They were almost countable, but not quite, because individuals were constantly taking to the air or landing; and as a car would go by, the entire flock would take off only to land again after the car passed.

On the 30th of August (I think), the entire population, except for the few who still had babies in the nest, took to the air and left.  That’s a week or 10 days early.  Why?

Years ago, one morning early in September, I was milking my cow down at the calving barn.  I observed that hundreds of swallows were lining the power lines.  All of a sudden, as I watched, they arose en mass, and were gone.  They’d begun their southward migration.

I have all sorts of questions about my friends, the swallows.  How do they all know that it’s time to leave?  Who gives the signal?  How do they communicate the information to each other?  How do the various flocks all know to leave at the same time?  How is it that both species of swallows, the barn swallows and the violet-green swallows, know to leave together?  Or do they?  Have I just not noticed that they leave separately, but at about the same time?  Is their leaving based upon nighttime temperatures, upon the position of the sun, upon day length, or upon the availability of mosquitoes, their food source?  Or is it all of the above?  Mosquitoes stop hatching as fall approaches and temperatures go down.

How do the swallows that are left behind feel?  Are they anxious, desperate, lonely?  Do they have a hard time finding enough food for their babies?  Do they eventually catch up with the main flock somewhere along the way?  Are those thousands of birds all migrating together in one great flock?  Do they stop along the way, or are they in a headlong flight to reach their destination?  How long does it take?  Are they flying low where they can pick up an occasional insect, or are they up high where flying is easier and predators are fewer?  Are they following a waterway or a flight path, or are they flying over mountains?

And just where are they going?  Mexico, I presume, but where?  Do they raise another family or two down there before they return here?  They’re only here for five months, April through August.  How long do the transits take from Mexico to here and back?  And why are they leaving so early this year?  Do they know something that humans don’t?

I wish that I could attach a radio transmitter to some of my little nestlings and learn where they go and what they do.  Is the pair that’s nesting above my door the same pair that nested there last year, or is it their kids?

My swallows are an interesting, happy community living among this separate community of humans.  They’re joyful.  Everything about them seems happy—their twittering among themselves, and their swooping, diving, whirling flights.

I love my swallows.