Over the noon hour today Iain Rayner found an adult Slaty-backed Gull on
Little Lake in Peterborough. Don Sutherland and I were able to see it
before it flew north with a Herring Gull at 1:40 pm and observed many field
marks which were consistent with the identification to that species. To my
knowledge it has not been refound at this point despite some searching but
there aren't many places where gulls routinely congregate in Peterborough
at this time of year other than Little Lake (numbers usually peak around
lunch time each day with gulls gradually filtering away through the
afternoon). It's possible it will return in subsequent days but there is
daily turnover here and we speculate some of "our" gulls also visit places
on Lake Ontario such as Cobourg Harbour.
The bird was viewed from the Mark St. boat launch as well as from Edgewater
Boulevard.
Good birding,
Mike Burrell