The field season is mostly over. My field assistants are back in classes; my mist nets are packed away. (Many thanks to the people who kept us fed and equipped by donating a total of $1450 to this field season!) It’s grant-writing, lab work, and data analysis season now.
Well, almost. I really want to know what the juncos do when summer ends. Our working assumption is that they migrate down the mountains to escape the worst of the winter weather, but we don’t know how far they go, or when, or, really, if they do that at all. So this week I went back to look for them.
At one of my high-elevation sites, they do seem to have left. Where there should have been at least seven banded juncos, two unbanded adults, and three unbanded juveniles, I could find just one lone unbanded adult.
Yet at a nearby high-elevation site I spotted three adult juncos foraging with a White-crowned Sparrow, and a pair of juveniles, looking like brown-washed versions of adults after their fall molt, foraging and calling out whenever one got too far from from the other. Perhaps these were laggards, late in migrating downhill? All of them were unbanded, at a site where we had banded 24 juncos, suggesting to me that they might have originated even higher up the mountain—but then again, that site always seemed to have an unlimited supply of unbanded juncos.
The story was different still at my mid-high-elevation site. There—after a rather sleepless night spent watching a white pickup truck drive up and down the length of the near-deserted campground like a pacing tiger, and observing that it is possible to hear one’s own heart beat and that it sounds like approaching footsteps—I saw flocks of eight, ten, fifteen juncos flying and foraging together. I even resighted ELEA. So those juncos haven’t gone anywhere.
I was happy to see ELEA again. He was only the second junco we banded this year, and he has been reliably on his territory every time we’ve revisited this site. I hope he makes it through the winter. I saw a Sharp-shinned Hawk, a small raptor that preys on smaller birds, so cold and starvation aren’t the only threats the juncos at this site will face.
I’m wondering now how long the road to the site will stay open. I’d like to go back in a few weeks to see if the juncos are still there.