One Nest at a Time

Mosque on the main drag in Karadyi

The general plan these days is for me to get up early, drive to a site or two and try to record several songs from a focal male we have already banded. In the afternoon, we either rest, do data entry, band nestlings, or do nest checks. At night we try to band as many birds as possible. Lately we've been catching about two pairs (both male and female sitting on the nest) each night and luckily we also netted a few birds that had slipped away and not shown up for several clear nights in a row. 

A relatively dark male with huge tail streamers and his mate

So things are going very well: we've now banded 36 adults and 38 nestlings--which brings me to my next point. The reason I am here, as opposed to Colorado or almost any other place in the Northern Hemisphere, is that I am interested in studying a contact zone between two subspecies of barn swallow. Since nobody knows exactly where these contact zones occur, I was lucky to find Hakan, who had previously seen birds he visually assigned to both subspecies in this area. When I came here last August to briefly meet Hakan and check things out, I saw very light-colored birds, and some which I also thought were way too dark to be of the European subspecies. But there is not currently any clear dichotomy between subspecies, so we have to try to piece subspecies identity together with a handful of clues. We look at streamer length (the European subspecies have longer streamers on average), color (the Middle Eastern birds are darker on average), and we will look at the ratios of isotopes in their feathers to determine the approximate location of birds when they molted (i.e. where they migrate). Given that there is quite a bit of overlap in the other two characteristics, this last bit should be really helpful to figure out which subspecies intermediate birds belong to, since the Middle Eastern subspecies only travels short distances to winter, while Euro-swallows will fly as far as South Africa to winter. (Though why they would fly back to Europe and miss the World Cup this year is beyond me.)

In any case, the fact that we have banded birds of drastically different streamer lengths and colors looks good. Also, there seems to be a huge difference in the beginning of reproduction within our population, since we will have banded over 50 nestlings

A female perches on my hand for a while after banding

by next week and many of the birds in our study have still not laid their first egg. This is consistent with the transitiva subspecies not migrating as far and being able to return and get started with breeding earlier than their European rustica counterparts. But this is all preliminary and only after we've gotten the isotope results will we have an idea of whether or not birds in our population do have two distinct migratory behaviors. And I am also trying to record as many males as I can in order to see if there are any consistent song differences among dark vs light or early vs late-breeding birds. We currently don't know anything about song in any subspecies of the barn swallow except the European, and any differences are VERY subtle, so it's hard to know what to look for. But, more on how I'll go about answering my song questions later.

Hasta luego,

Matt
Daily Dose of Turkish: Seeya later--görüşürüz (goora shoo-russ)