Sunday, September 26, 2010
Banding in Montecristo
If you have already donated to the SalvaNATURA birdathon, you are a sponsor of our permanent bird monitoring program, carried out in three national parks in El Salvador, and one biological reserve in Honduras (see previous post).
One of those three Salvadoran sites is National Park Montecristo, in northwestern El Salvador, near the borders with Guatemala and Honduras. At this site, two monitoring (banding) stations are operated: one in cloud forest, and one in pine-oak forest. Each month, a team of biologists from SalvaNATURA visits the site for 25 hours of mist-netting at each of the two stations. This week, I joined Roselvy Juárez and Carlos Zaldaña for the September pulse in Montecristo. We were there from Monday evening until Saturday morning. We were able to put in the 25 hours at the cloud forest station, but heavy rains curtailed our time at the pine-oak station. It is still the rainy season down here in Central America, and the weather forecast for this week is for prolonged periods of sometimes heavy rain. Hopefully things will lighten up a bit during the second half of the week, so we can go back to Montecristo and do the remaining 14 hours of banding at the pine-oak station.
Good! Today I want to share with the readers of this blog a look at how bird banding stations, including this one, operate. I have some footage of a bird being processed. It is not complete, for it doesn't show how the bird is removed from the mist-net for example, but it may give an idea of what kind of data is collected in our bird monitoring program. This is your donation dollars at work!
When a bird is removed from a mist-net, it is placed in a bird bag and carried back to the processing site. There, the bag with the bird inside is weighed...
Next, the bird is extracted, and the bag is weighed without the bird. Weight of bag plus bird minus weight of bag equals weight of bird, right? The bird, incidentally, is a Brown-backed Solitaire, a resident species of Central American pine-oak forest. It weighed 38.5 grams.
If the bird is unbanded, the first thing you want to do after removing it from the bag, is put on a coded bird band. This will allow the individual to be recognized the next time it is caught. Recaptures provide fascinating insights into the life history of birds. Resident birds like this Brown-backed Solitaire are banded with colored plastic bands that you can slide on in the manner shown here.
With the bird band on, some first data are recorded on a bird banding sheet. The code of the bander is noted, as well as the code of the bird band, the species' scientific name, and its weight. Other data collected include the time of capture, which mist-net, name of the station, the presence or absence of a brood patch, presence/absence of a cloacal protuberance, fat score, molt status of body and wings, wear of the primaries, and ossification of the skull.
As Roselvy is looking for plumage details in order to accurately age this bird, another individual of the same species can be heard singing in the background. Listen also for Roselvy's explanation - in Spanish - as to why this individual is a second-year bird...
Measuring the wing cord, i.e. the length of the closed wing from carpal or bend of the wing to the tip of the longest primary feather, is also standard procedure for processing a bird.
Pretty neat, huh?
For more photos of this particular banding trip, please go to our facebook page, where you will find a photo album called "September pulse, Montecristo". And if you want to support this program, please go here for instructions on how to do that. Your support is greatly appreciated.