Kestrel Watch of the University of Minnesota Raptor Center is trying to solve a mystery:
Since about 2000, The Raptor Center has seen a precipitous decline in the number of kestrels admitted to the center; from 107 admissions in 2000 to only 22 last year (see chart in Statistics). At the same time, admissions of Cooper’s hawks have doubled, from 54 admissions in 2000 to 114 last year. At this point, no one knows whether these findings are correlated, or even whether the reduction in kestrel admissions represents a decline of the species in the wild…
Through Kestrel Watch, The Raptor Center hopes to decode the rapid decline in American kestrel admissions. To join Kestrel Watch, all you need to do is brush up on your observation and reporting skills. When you see a kestrel, record the day and time of your observation. Make note of what the bird was doing. Was it hunting? Perched? Feeding? How many kestrels were there? If you feel comfortable identifying the bird’s gender, report that, too.
You can submit your observations and photos on the Kestrel Watch website. They also have great information on identification and natural history. You can even see on a map where others have spotted Kestrels.
I checked out the HawkCounts for Hawk Ridge in Duluth, MN, and it looks like Kestrels should be migrating through that area until early November. Kestrels also stay year round in southern Minnesota. But you don’t have to be in Minnesota to participate. Observers have been reporting in from all over the Midwest.
While I was at the Hawkcount website, I also checked out the number of Kestrels seen migrating through Hawk Ridge since 2000. I even made a quick line graph because I’m a dork cool like that.
From the graph, it seems that the number of observed American Kestrels migrating through is decreasing. However it is variable and dependent on the number of hours of observation, weather, ect. Their data goes all the back to the 70’s, but I wasn’t feeling that ambitious (all the data is online though if you are interested). I was going to also graph the number of Cooper’s hawks observed to compare with the Raptor Center’s data. However, Cooper’s Hawks don’t migrate much to the north of Lake Superior so they only see up to a couple hundred per year at Hawk Ridge.
So, Are American Kestrels being taken over by Cooper’s hawks, or are Cooper’s hawks just becoming more accident prone while Kestrels are getting smarter? What do you think? Whatever the case, The Raptor Center doesn’t know and needs your help to find out.