Wednesday, March 14, 2007

Bird Bander

I'm a bird bander. It's probably important to know about me, because it'll come up now again, here on the blog or in normal conversation.

I am authorized by the Bird Banding Laboratory--in Laurel, Maryland, and currently within the US Geological Survey--to affix uniquely-numbered aluminum bands to the tarsi (the part of the leg above the foot) of most North American species of birds. Banding enables researchers to re-identify individuals themselves and--with the help of other biologists and the general public--to find even those birds that have flown halfway around the globe from where they were originally captured.

A Master Permit for banding birds has become increasingly difficult to come by in recent years (though there are many of us out there). The criteria for obtaining a permit include 1) a need, that is, a particular research project or question that would require or be augmented by the kind of information that banding provides, 2) demonstrated capability at identifying, ageing, and sexing the species of birds one might capture, and 3) organizational skills (to deal effectively with the potentially vast amount of data that needs to be reported). To obtain a permit today requires having favorable references from three individuals who already hold Master Permits. Additional permits are required for banding special birds, such as endangered and threatened species.

The sort of information obtained through banding (which is called "ringing" in Great Britain) includes site fidelity, migration patterns, turnover rates, dispersal distances, and longevity. From time-to-time, I'll probably share some interesting stories (from my own and other avian research) that has to do with this integral part of bird research.

Should you ever find a banded bird (pigeons don't count--that's a different band system used by racers of homing pigeons), record the number and contact the Bird Banding Lab.


Anonymous said...

I've always wondered if that kind of thing hurts the animals?

Rick Gerhardt said...

Hi Tori:

No, tarsal bands are used because they have been determined to have no effect on the bird. There are a wide range of sizes, and the exact size of band appropriate to each species is well-established. A proper-sized band spins freely around the bird's leg, but does not slip up or down over the joint above or the foot below.

There are a very few species for which leg bands are not used. Turkey Vultures (the subject of a recent post on my blog) cannot wear a band for a rather unusual reason. These birds defecate (a rather liguid feces) on their own legs (apparently especially in hot weather and then as a way of cooling themselves). This feces was shown to solidify in and around a leg band to the point that it restricted blood flow and caused necrosis. As a result, it is illegal to use leg bands on Turkey Vultures.

Anonymous said...

Rick, perhaps you can write a little post about robins. I really have quite a time with robins, especially around the time they begin to build nests (April/May). There seems no way I can discourage them from building nests beneath my deck other than by getting my bb gun out. And even then they come back and rebuild after I've scared them away. They are the most tenacious creatures I've ever come across. If I knock down their nests, they are right back building a new one within hours. If I leave for a few days during this period, I come back to a bunch of new nests. It seems that a group of males bring materials for a nest to the female, who builds it. Even when there's not a female around, the males will continue bringing the nesting materials, which of course create a mess everywhere. What can I do to get rid of these birds?

Anonymous said...

Hey Uncle Rick, I had no idea about the Turkey Vulture's "specialized" cooling method. Rather humorous though. It's also interesting they do this in hot weather, since producing a more solidified feces would conserve water within the body, right? Is there another method researchers track them?

Rick Gerhardt said...

Hey Ben:

Yes, folks who want to identify individual Turkey Vultures generally use patagial (wing)markers. These are actually much more visible (than leg bands) and readable (they usually include a combination of letter and number that is unique, making identification of the individual possible) at quite a distance.