Now is the time of year when many bird observatories begin their fall banding season, placing sometimes thousands of uniquely numbered aluminum bands on birds all across the continent. Why do scientists band birds? What is the importance? And don’t those bands negatively affect the birds in some way? I’d like to address these questions with a few specific examples.
Okay, so why do scientists band birds? There are so many answers to this question, but I will start by placing it in the context of long-term monitoring. Fall migration banding stations run by organizations such as the Intermountain Bird Observatory band thousands of birds every year, and some of them have been doing so for 15, 20, even 30+ years. Citizen scientist Alfred Larson, highlighted in our recent film Bluebird Man, has banded over 25,000 bluebirds over the last 35 years.
By banding in the same area for many consecutive years, scientists give themselves a chance to recapture birds they have already banded. While recapture rates can be quite low, they give researchers a glimpse into such importance life-history traits as survival, longevity, movement, site fidelity and body condition, among many others.
People, especially bird watchers, can greatly assist scientists by reporting the sighting of bird bands to the Bird Banding Laboratory. I had the opportunity to report such a sighting earlier this summer. I saw the above color-banded Semipalmated Sandpiper on May 21, 2014 foraging near the mouth of the Nome River in northwest Alaska. I reported the sighting to the BBL, and just recently heard back about the origins of this bird (you get a neat Certificate of Appreciation when you report a sighting).
The bird was banded as an adult in June of 2012 near Cape Krusenstern in northwest Alaska. Now what does that tell us? A lot of things! First it tells us that this bird is at least 3 years old, and may be older as it was banded as an adult. Second, Cape Krusenstern is located north of where I re-sighted the bird indicating that the location of my re-sight, the Seward Peninsula, may be an important refueling location for the spring migration of Semipalmated Sandpipers. Lastly, this individual has been wearing these bands for almost 2-years and is still alive and in good condition, meaning that the presence of these bands has not negatively affected her survival.
I want to finish this discussion with another example I just encountered last week. I snapped this photograph of a banded Arctic Warbler as I was assisting a team of USGS biologists set up mistnets to capture songbirds. This was the same location they had captured songbirds the year before, and once we opened the nets up it did not take long to recapture this male warbler of the Old World.
While some photographers would no doubt be frustrated to capture a photograph of such a unique bird with a metal band on it’s leg, I was ecstatic. Why?
For starters this means the bird has used almost exactly the same breeding site two years in a row, an important life history trait known as breeding site fidelity. It also means the bird is surviving just fine with it’s now 1-year old jewelry. Alaskan Arctic Warlbers migrate all the way to the Philippines and Indonesia every winter, and this warbler made that journey and back again with this band on it’s leg.
Bird banding is an important scientific tool, so if you’re a bird watcher, remember to be on the look out for banded birds! You’re sighting and corresponding report to the Bird Banding Lab will help scientists continue to unravel the mysteries of the natural world.
If you have a specific opinion for or against bird banding, please leave us a comment, we would love to hear from you.
Tags: band, banding, BBL, birds, research, resight