31 October 2010

Franklin's Front

Franklin's Gull has turned up in almost every state and province in North America. Its migration corridor in the United States is directly through the Great Plains where hundreds of thousands can be found annually. In the Midwest, Franklin's is uncommon to rare but more common in the fall. In Illinois, for instance, Franklin's Gull is left unchecked on most birders' lists in the spring due to this species' hurried nature to get to the breeding grounds. Midwestern states east of the Mississippi River have a much better chance of observing Franklin's in the fall, particularly in late October after a cold front has passed. I've learned that tracking weather systems for this species, as magical as it may seem, is for the most part reliable and predictable. The ideal parameters involve areas of low barometric pressure with a strong west to northwest wind with the passage of a cold front.

Basic Adult, 64th St Beach, Chicago IL; 27 Oct 2010
I recently spent some time researching Franklin's Gull records in the lower 48 states and I remember reading in "Birds and Birding at Cape May" by Clay and Pat Sutton, that Franklin's Gull was recorded in record numbers in 1998 at the Avalon Seawatch. This event took place after a strong low pressure system ripped through most of the Midwest and north through Canada. At the time, I remember distinctly asking myself how this record number, which to my recollection was under 50 individuals, could be associated with a low pressure system in the Midwest.


On 26-27 October 2010, the Midwest and surrounding central states experienced the lowest barometric readings ever recorded away from the sea coasts. The damaging winds and thunderstorms were likened to a Category 3 hurricane. I was on standby and waiting to see if indeed Franklin’s would pass through with the cold front. The night before, birders Bob Hughes and Michael Retter explained how the conditions were ideal for Franklin’s via the Illinois Birders’ Forum. Sure enough, as the cold front passed through the Midwest, reports of Franklin’s Gulls began to pour in.

Illinois, Indiana, Michigan, Ohio and Wisconsin all reported Franklin’s Gulls on 27, 28 October, 2010. My home state, Illinois, reported at least six distinct sightings with the 64th St Beach along Chicago’s lakefront tallying a site-record of 47 individuals (Paul Clyne). Wes Serafin reported a group of 20+ at Saganashkee Slough, an inland lake in southwest Cook County, IL. Ohio reported a flock of 29 at Caesar Creek Beach. Caesar Creek is in the southwest part of the state where only 1-2 individuals are recorded in the fall (Larry Gara). And if one needs more evidence that this was no fluke, New York also recorded two individuals as far east as Suffolk County (far eastern NY). Keep in mind that Franklin’s is casual to very rare along the Atlantic coast (Howell and Dunn, 2007). Did the birds intentionally avert the storm by shifting their migration route eastward or did the storm blow them east as they were migrating? Regardless, the conditions inherent in these storms are what I’ve come to call “Franklin’s Fronts” - experienced birders await them and expect to see Franklin’s Gulls trailing behind.


I found some time to make it out to the 64th St Beach in Chicago on 27 October, 2010. The winds that day were like none I've experienced on the lakefront outside of winter. The Saganashkee Slough flock was seen leaving in earnest at sunrise the next morning; This is typical of moving flocks of Franklin's, rarely dwelling for more than a day or two away from established staging areas.

All photos were taken on 27 Oct 2010 at 64th St Beach


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