With the last couple of mornings facing poor weather conditions for banding operation, we've had some time off to enjoy the birds through binoculars instead of in the hand. Birds are certainly on the move, and we're hoping for better days ahead so that we can open nets again.
In lieu of sharing a cool bird with you, I thought I might share some terminology from the bird bander's vocabulary about previously banded birds, stay tuned for the next installment on banding vocabulary as the season progresses.
Banding (or ringing): the process of placing a tag that has a unique identifier (often a number) on a bird. North American researchers refer to this process as 'banding', while European researchers often refer to it as 'ringing'. 'Ringing' is a reference to the shape of the tag that is used on birds (a small circle, or ring, that is placed around the leg of the bird.). See a demonstration of how it happens here.
"new": this is often how we reference the "status" of a captured bird. Any bird that does not have any type of marker or band is classified as 'new' and thus is a valid candidate for having a band placed on it. Remember, we do not place additional bands on a bird that is already banded, and we do not replace bands unless they cannot be read or the band is defective.
Capture: this describes the act of entrapping or restraining a wild bird using permitted techniques for study by a licensed bird researcher.
Foreign: a type of recapture, this refers to a bird that is captured by a banding station that it was not originally banded at. For example, we have captured a couple Sharp-shinned Hawks over the years that were originally banded by other researchers in Canada and the lower 48 (most recently- Alberta, Canada!).
Recapture: any bird that has already been banded that is captured by a banding operation (or other bird researchers).
Return: a type of recapture, this refers to a bird that is recaptured at it's original banding location across years. The assumption is that (for a migratory species) the bird leaves the area and then comes back; this is powerful information and provides clues about timing, fidelity to stop-over or breeding locations, and even clues about longevity and physiological fitness. Examples of returns from this year are the adult Hammond's Flycatcher and Dark-eyed Junco captured earlier this season; they were originally banded here at CFMS in 2019 and returned this year (2020).
Repeat: a type of recapture, this refers to a bird that is recaptured within the same season at it's original banding location. Examples of repeats are the birds (usually young birds) we often catch for multiple days in a row while they "hang out" in the area surrounding the station before moving on in their migration. (Sometimes a bird can be both a repeat and a return; for example, think of 2019's Bob and Mrs. Bob - two Black-capped Chickadees that were captured multiple times that spring, but had been banded previously. The first time they were captured, they were a 'return' but each subsequent recapture that spring they were 'returns' and 'repeats'.)
Recovery: this is not a type of recapture; this refers to a bird that has a band but is encountered, often dead, by anyone in a research or nonresearch setting. This might include a bird that is found dead from known or unknown causes, or a bird that is injured and in custody of a licensed rehabilitator. For example, a recovered Swainson's Thrush that died from a window strike earlier this year had a band (story here).
Resight: this is not a type of recapture; this refers to a bird that is observed in a natural setting and it's band number (or identifier) is read and recorded without capturing or impeding any normal behavior. This is often impossible with songbirds, because their bands (and thus the numbers on them) are too small to be read by an observer. This is more common with larger species like Sandhill Cranes that may have large colorful bands with large letters that allow them to be easily read through binoculars or a scope. If you see a bird with a band, you can report it here and get the original banding information about the bird (where and when it was banded, how old it is and maybe even what sex it is).
Questions? Leave a comment on this post and we'll get back to you!
~Claire
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