2024 Bird Banding MAPS Station Summary

The COS Bird Banding and Audubon Great Lakes Restoration Intern crews. Photo by Emily Osborne.

words by Stephanie Beilke

This year marked the fifth year of the operation of Chicago Ornithological Society’s Bird Banding MAPS Station at Big Marsh Park and one of our most successful seasons of data collection yet!

The team is still crunching the numbers and entering data, but we are proud to announce that this year we were able to run the station for seven of seven mornings that were scheduled. This is because in previous years there was always at least one day where we had to cancel and were not able to reschedule due to weather or volunteer unavailability. Twenty-six dedicated volunteers turned out over the season to help make this happen! So, hats off to all our incredible volunteers for waking up at 3:30 a.m. and putting in their steps (sometimes up to seven miles per day) to make this bird banding season possible!

As we have for the past four seasons, our Bird Banding Station operates a protocol called MAPS (Monitoring Avian Productivity and Survivorship). Through the MAPS protocol, we use capturing, tagging, releasing, and occasionally recapturing birds to investigate how well breeding populations of songbirds are doing. We do this by looking at approximate number of young produced and how long songbirds live. According to this year’s preliminary results, we banded 208 birds of 24 species in 2024, and there were 41 recaptures of 9 species. (Note some of these may be duplicate individuals since we haven’t crunched the numbers yet.)

Least Bittern. Photo by Stephanie Beilke.

Our top three species banded were similar to previous years: Gray Catbird (55), Yellow Warbler (30), and American Robin (21). American Goldfinch snuck into the top five for the first time ever with 15 newly banded birds, and Song Sparrow snagged the fifth spot (10). Our unusual finds included the station’s first ever capture of Red-eyed Vireo, likely still migrating since they were captured on May 31, and an early-departing Swainson’s Thrush, which was captured on August 3. I think I can speak for the entire group though when I say that our topmost highlight was catching not one, but TWO Least Bitterns. Unfortunately, we did not have the appropriate band size or permit available for banding Least Bittern, but we took the opportunity to get some measurements and photos before letting both individuals quickly on their way. A bird banding experience of a lifetime for many of our volunteers!

In addition to working with many volunteers, in 2024 we also hosted a successful demonstration in partnership with the Feminist Bird Club Chicago and hosted the Audubon Great Lakes Restoration Intern crew, who stopped by to learn more about banding. Thanks to all who have supported the COS Bird Banding effort! We look forward to sharing more updates once we have finished reviewing this year’s data.