It’s easy to take the common species of our beloved birds for granted. It’s almost a guarantee that we can look out our windows and see a Northern Cardinal in the bushes, hear a Blue Jay yelling from the tree canopy, or await the return of Canada Geese in the spring. Our day-to-day life would look and sound pretty different without these reliable characters, which may be suffering quietly despite their relative commonness. One such bird is the Common Grackle, a lanky blackbird with a striking iridescent blue head and piercing pale eyes, which has declined nearly two percent per year (54% overall) between 1966 and 2019, according to the North American Breeding Bird Survey. In 2023, we were contacted by Kelly VanBeek, Midwest Grassland and Native Seed Strategy Coordinator with the US Fish and Wildlife Service, who was working on a Common Grackle research project and needed a location near Madison to catch grackles.

*Emma Raasch holds a juvenile Common Grackle with a GPS tag affixed to its back (photo by Anne Readel).*

We were excited to help Kelly with this important research by trapping grackles at Goose Pond Sanctuary. Since Emma was already setting traps to band Mourning Doves for the Wisconsin DNR, she started monitoring them for Common Grackles as well. It’s always a privilege to interact with birds so closely, and she loved seeing the juxtaposition between their sweet, docile nature and their stern, intense expression.

Kelly offered insight into the reason for the study and what they’ve found so far:

*A GPS tag with a harness made from elastic thread so the tracker can be safely affixed to the back of a Common Grackle (photo by Anne Readel).*

*Kelly VanBeek, a biologist with the US Fish and Wildlife Service, places seed around live traps at Goose Pond in June 2023 (photo by Anne Readel).*

“Grackles are a common bird in steep decline based on recent assessments by Partners in Flight. Why they are declining so precipitously is yet unknown and puzzling given they are largely considered a habitat generalist. Recent work undertaken by Mike Ward’s lab at the University of Illinois at Urbana-Champaign revealed high nest productivity and nestling survival, so our pilot study was undertaken to attempt to understand migratory pathways and overwinter survival of tagged birds.
We initially purchased 14 satellite transmitters. We were able to recover a few tags from deceased birds, ultimately allowing 16 different individuals to carry tags at some point during the pilot study. We placed transmitters on 4 birds from Goose Pond. Goose Pond was a great site to utilize because of the existing banding efforts by Emma on Mourning Doves that we could leverage to also trap grackles. Having staff on site was extremely helpful for tag deployment.
It’s difficult for us to say how many of the individuals carrying tags died during the late breeding, migratory, or winter season, or if the satellite tag simply failed. We were able to recover portions of 3 carcasses, including 1 carcass at Goose Pond that was likely depredated by an aerial predator. We suspect at least 3 other individuals died, but transmitters could not be recovered.
We were able to track 3 birds from Wisconsin to locations near Effingham, IL during the non-breeding period. An individual captured in IL was located near Terre Haute, IN during the non-breeding period. One individual, a juvenile captured at Goose Pond, did have a transmitter that lasted until the following spring, where it was once again located near Goose Pond on its last transmission.”

We look forward to reading their peer-reviewed paper on why Common Grackles are declining once it is published. We also enjoyed working with Anna Readel, who photographed grackles in the hand and on the wing at Goose Pond and Wildland, LLC. Anne is a wildlife photographer, writer, lawyer with a PhD in conservation biology living in Madison.

*Grackles roosting at Wildlands in August 2023 prior to migration (photo by Anne Readel).*

In August 2023, Anne was looking for a place to photograph fall staging locations of grackle flocks. On August 1, Mark and Sue observed 700 birds leaving the cattail marsh at Wildland from 6–7AM. Their high count was at least 1,500 on August 21—with multiple flocks of 100 to 700 birds moving between the marsh, woods, and food plots. Anne was able to capture a few large flocks in photographs the next day.

Mark and Sue enjoy telling their friend Jerry Martin about high counts of birds. When they saw a flock of 500 Mallards, Jerry replied, “Are you sure there were not 501?” When they told Jerry about their high count of Common Grackles and showed him a photo with 784 grackles, he asked if they were sure. Mark then showed him another version of the photo that had exactly 784 blue dots differentiating each individual bird!

Common Grackles nest at Goose Pond in our decades-old Norway Spruce. The birds may nest high in conifer trees, often near water, in colonies of up to 200 pairs. The high eBird count of 150 Common Grackles at Goose Pond was by Bill Hilsenhof on June 4, 1961. Bill found 52 species that day, including many that we now rarely see in early June. He also has the first eBird report of Common Grackles at Goose Pond in 1958. It is interesting to look back at eBird reports from 65 years ago. John Romano holds the current Columbia County record for counting 5,000 Common Grackles (along with 4,000 Red-winged Blackbirds) at the Mud Lake Wildlife Area east of Poynette on October 29, 2009.

Written by Mark Martin and Susan Foote-Martin, Goose Pond Sanctuary managers, and Emma Raasch, Goose Pond Sanctuary ecological restoration technician
Cover image by Anne Readel. A flock of Common Grackles takes flight over Wildlands in August 2023.

Common Grackle Research at Goose Pond Sanctuary

Further reading