It was a splendid Saturday morning. The last one of an Indian summer, perhaps. Perched high above in a tree, a goldfinch chattered. Strings of aluminum bands and piles of bird field guides lay scattered about the picnic table in Biocore Prairie near Picnic Point.
Only three volunteers showed up for one of the last bird-banding sessions of the year: supervisor Jackie Edmunds, wildlife undergraduate Kelsey Rayment and me.
“Bird banding” pretty aptly describes what we did that morning: putting little aluminum bands on birds’ legs. Though that’s the main objective, we took a bunch of other measurements too, with intellectual-sounding names like “wingchord,” “nares-to-tip” and “cloacal protuberance.” What are those? They’re pretty much just fancy names for “length of wing,” “length of beak” and “length of cloaca.”
How to catch the birds? We set up temporary mist nets — essentially oversized volleyball nets — which the birds fly into and get caught. One was in a thicket and kept getting caught in the branches. I was designated the un-tangler, which meant tediously plucking the thin mesh off of buckthorn twigs.
Since it was late October, most birds had migrated south, but we hoped to catch some late migrants. This particular station doesn’t band below 50 degrees, Edmunds said. The birds can’t handle the stress of being cold and of being held by a looming figure whose other hand grasps cold pliers and pointy micrometers. She mentioned that the informal weather policy is for the volunteers’ sake as well.
For all of their fluttering about, sometimes birds just do not fly into the nets. Maybe it’s because they can see the net, or maybe because they just like spiting us. When that happens, we use techniques that strongly encourage them to fly in. Such techniques include flushing – that is, startling a bird in the direction we want.
That’s how we caught our first bird, a Swainson’s thrush. Rayment untangled it from the mesh and put it in a paper bag for its journey back to the picnic table. I first weighed the rustling bag/bird combo, then pulled the creature from the bag. As I held it, the thrush pooped, spewing some green gel-like stuff all over.
When banders hold birds, sometimes it looks like a death grip. I promise you it’s not. They just have to ensure that the little feathery munchkins don’t fly away. Even with these specialized handling techniques, the birds can still escape.
This one didn’t though. I clasped a metal band around its leg and measured its wings, tail and beak. That was the easy part. Then for the more ambiguous data point — age. Figuring out age and sex is probably the biggest challenge that banders face, Edmunds said. Plumage can often help determine sex, and tail length can sometimes work to tell age. However, we needed to consult a higher power, meaning a really big reference guide. Rayment flipped through the binder, bulging with unexciting charts and obscure avian terminology. We guessed female based on tail length, then released the thrush back into the thicket.
All the notes we take go into a U.S. Geological Survey database, which has collected similar information since 1960 from many countries. People can request data if they supply a good reason, like some sort of research. Worldwide, volunteers have banded over 64 million birds. Biocore Prairie’s total of about 7,500 isn’t quite so staggering, but it’s still impressive. UW administrator (and master bander, meaning certified to catch and band birds) Mara McDonald started the station in 2001 as a way to see if the restored prairie affected bird diversity. And it did. A wider variety of birds were caught in the 17-year-old prairie versus the 9-year-old prairie.
Lots of people find out about the bird banding station via chance encounter on their walks, like one couple that stopped to chat briefly with us. Upon leaving, they wished us well.
“Catch another Swain, uh, whatever it is,” the man said.
It was later morning by that point and we had given up hope of catching anything more than that one bird. But just as Rayment and I started taking down some nets, Edmunds appeared with a chickadee and another thrush.
The chickadee had a few colored bands from a different study, but they were on too tight so its foot was swelling up. This chickadee will probably be OK, but others are not so fortunate. Sometimes birds get so tangled in the nets that they hurt themselves trying to escape. Injured birds are taken to the Four Lakes Wildlife Rehab Center, where Jackie is co-coordinator, and volunteers check the nets every 15 minutes to try to prevent injurious entanglement.
After we let those two go, Edmunds came back with yet two more thrushes. At that point, she took down the net to quell this sudden onslaught and to prevent us from spending all afternoon banding thrush after thrush. While Rayment expertly weighed one of them, I let the other escape. My blunder proved that though we may catch our feathered friends temporarily, they will always find a way out.
Correction: The original article incorrectly labelled Jackie Edmunds as a master bander; the article has been changed to reflect that Mara McDonald is a master bander. The article has also been changed to reflect the process of dealing with injured birds.
