Illinois’ Three Successful All Volunteer Hawkwatches

Jul 16, 2020

Ask most birders or hawkwatchers around the country about famous sites they’ve heard of and I’d guess not one from Illinois would be mentioned. But Illinois is home to three successful all volunteer-run hawkwatch sites that are conducted every fall. The first one, the Illinois Beach State Park Hawkwatch, located in the northeastern corner of the state near the Wisconsin border along the shoreline of Lake Michigan, began in the year 2000. Observers at Illinois Beach average a little over 600 hours per season with an average of 5165 raptors counted. That number in and of itself may not be too impressive but Illinois Beach has one noteworthy distinction. No hawkwatch site west of the Atlantic Coast sites tallies more Merlins than Illinois Beach does with an average seasonal count of 408 over the 20-year stretch. Illinois Beach’s October 9, 2007 total of 708 Merlin still ranks amongst the highest for a single day total ever in North America. Illinois Beach is also a participating site in the Raptor Population Index (RPI), co-sponsored by four leading raptor organizations in North America. More information on RPI can be found at: Moving further down the Lake Michigan shoreline only 17 miles away is the Fort Sheridan Hawkwatch. This site formerly began in 2013 as an exploratory site to compare sightings with Illinois Beach on favorable days for raptor migration. In that first year only 88.75 hours were put in. But in that short amount of time raptor counts in comparison to Illinois Beach were showing some interesting differences. Not only in daily totals but also in what species were sighted. Now, seven years later, Fort Sheridan is on its way to becoming another successful all volunteer Illinois site that will hopefully teach us something about raptor movements along the shoreline of Lake Michigan. The third established all volunteer site in Illinois, the Greene Valley Hawkwatch, was started in 2006. It is located approximately 52 miles in a straight line from Illinois Beach and inland about 25 miles from the shore of Lake Michigan. The site itself is located on a hill at a closed landfill. Being an inland site overall numbers are different than the other two sites in Illinois but one species stands out. It was long suspected even before Greene Valley was started that Broad-winged Hawks were generally migrating away from the shoreline of Lake Michigan. And although the longevity of the three sites is slightly different, the average annual Broad-winged Hawk total for Greene Valley surpasses the other two sites. Greene Valley average per year is 1436 Broad-wingeds compared to Illinois Beach with 1078 per year and Fort Sheridan with 1206 per year. Several other areas of our continent have multiple sites in close proximity to each other. It is presumed and hoped for that something can be learned by comparing data at these sites and their relationship to each other. The three sites in Illinois are beginning to realize the potential for further research into this love we all have for raptor migration.