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Past Society Events
A Symposium on the Gulls of Lake Erie
January 8, 2005
An 8 January snowstorm did nothing to discourage about 125 gull enthusiasts, who met in the comfortable setting of Rocky River Nature Center in North Olmsted to learn about these birds. Jointly sponsored by the OOS and the Kirtland Bird Club, the event brought together folks who are used to freezing toes and blowing snows in pursuit of their quarry, and gave us all a unique chance to hear from three experts, as well as a couple of hours of prime-time field experience on the Lake Erie shore.
OOS President Jim McCormac presided, and first introduced Chip Weseloh, a biologist with the Canadian Wildlife Service, who has worked with gulls and other water birds in the Great Lakes for over thirty years. Weseloh described Lake Erie’s twenty known species of gulls, giving special attention to our four breeding species. He cast light on many features of local gull ecology, including nesting, migratory movements, contamination by pollutants, habitats and foods, behavior, distribution, and changing status over time. Beyond pollution, major human affects on gull populations include eradication of nesting habitat and new food sources in the form of landfills and winter warm-water outflows. For example, only a single pair of great black-backed gulls is known to nest in the Lake Erie area, and this predator from the top of the food chain absorbs twice as many organochlorine contaminants as the smaller herring gull, which may have led to its poor reproductive success locally. Further, the still smaller and more numerous ring-billed gull manages to fl edge about twice as many young as do herring gulls. Weseloh enlivened his informative talk with numerous anecdotes from decades of working with gulls; for example, gulls lay clutches of three eggs, and are so insistent on having three to incubate that a single female has been known to lay 13 or 14 eggs consecutively to replace single eggs repeatedly removed from a clutch.
The audience was next treated to a presentation from Larry Rosche, whose expertise with birds, and notably with gulls, is well known and deeply appreciated in forums such as this. Rosche treated the history and status of Ohio’s nineteen accepted gull species, providing documentary photos and witty and illuminating commentary on the changing populations of gulls and humans’ abilities to understand them, significant records of the past, the foibles of bird observers, as well as salient points of identification for each.
John Pogacnik spoke next, ably tackling a difficult subject, the many knotty problems inherent in gull identification. Drawing on decades of field experience with gulls on the Lake, Pogacnik offered an outline of the physical features most important to identification, the vagaries of field conditions, and problems associated with sexual dimorphism, racial differences, deformities, the effect of diet on soft-parts colors, albinism and melanism, and the seemingly growing problem of hybridism. For these challenges he offered a was not like looking for warblers, and that seven species of gulls variety of helpful facts, hints, and analyses.
After lunch, an hour-long panel discussion among participants fielded questions from the audience that ranged from inquiries about predictions of gull population changes, the next new gull species for the Lake, inorganic contaminants, migratory pathways, marsh restorations, and of course a host of ID topics.
The Symposium ended with a field trip to the lakefront and nearby warm-water outflow at E. 72nd Street in Cleveland. Gull sightings in recent weeks had not been good, and few organizers had high hopes for being able to do more than show participants the age classes of three or four routine winter species, but good scouting, spotting, and leadership, plus persistence by those who were able to stick around till darkness began to fall around 5 pm led to sightings by many of the following species: ring-billed gull, herring gull, great black-backed gull, Bonaparte’s gull, second-year Thayer’s gull, adult lesser black-backed gull, adult California gull, and an adult hybrid (apparently a great black-backed X herring cross). Larry Rosche had pointed out earlier that looking for gulls was not like looking for warblers, and that seven species of gulls makes a good day. In more ways than one, we had a good day.
Bill Whan
Columbus, Ohio
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