I have been attempting to document the number of individuals of the more uncommon gulls in the Duluth-Superior harbor during the fall and winter of 2009-2010, similar to what I did last season. Most of this is done by analyzing photos. Most photos were taken at the Superior Entry at the Minnesota-Wisconsin border or Canal Park in Duluth, though a few were taken at the Superior Landfill in Wisconsin. Almost all individuals were seen both in Minnesota and Wisconsin. and many individuals have been seen at multiple locations in the Duluth-Superior harbor area. By photographing such details as the primary patterns of adult Thayer's and Iceland Gulls, and the tail patterns of immature Iceland and Great Black-backed Gulls, I have been able to quantify the number of individuals of each age class for each species, and to track individuals birds as they come into the area, move from site to site, and even linger for months in a row. For example, the same first cycle Iceland Gull found at the Superior Entry on 28 October still continues to be seen in the area in January, and it has been fun to see the subtle changes in it's plumage (this bird now has extensive pink color at the base of the bill and is acquiring a little gray color in the mantle). I have put many of these photos at the same website as last season: www.pbase.com/karlbardon
Here is a summary of the number of individuals of the more uncommon gull species wintering in the Duluth-Superior harbor (many of which are still present). It has been an amazing season here for gulls, with Thayer's, Iceland and Great Black-backed all being seen in record numbers for this location. Thayer's Gulls : At least 40 individuals (I took photos of 14 adults, 2 fourth-cycle birds, 3 third-cycle birds, and 10 second-cycle birds, plus I also took photos of at least 10 first-cycle birds based on tertial pattern, but I am sure the number of first-cycle birds was much higher, at least 12-15 birds, probably many more). This compares to about 25 total Thayer's Gulls seen here last season. A maximum of 17 Thayer's Gulls were seen on 6 December 2009 including 6 first-cycles, 5 second-cycles, 1 third-cycle, and 5 adults. Most first-cycle birds have apparently moved on, leaving mostly adults. Iceland Gull: At least 11 individuals (I took photos of 4 adults, 2 second-cycles, and 5 first-cycle birds- the gallery shows each bird perched, in flight, and a detail of its tail or wing). This compares to 5 total individuals here last season. Maximum daily counts have been 5 both on 18 December 2009 and 3 January 2010, and 6 on 1 January 2010. Great Black-backed Gull: At least 16 individuals (7 first-cycle birds, 7 second-cycle birds, and 2 adults- all of these but one second-cycle bird were photographed). This compares to 5 individuals here last season. A maximum of 7 were seen on 1 January 2010. A total of 6 Great Black-backeds were counted at Canal Park alone on 5 January 2010. Lesser Black-backed Gull: At least 3 individuals (2 first-cycles and 1 adult, last seen on 2 December). This compares to 5 here last season. Slaty-backed Gull: Third-cycle seen 28 October-13 December 2009. Nelson's Gull (hybrid Herring X Glaucous Gull): adult photographed at the Superior Landfill on 1, 3 January 2010 Herring Gull: a partial albino photographed at the Superior Entry on 6, 20 December 2009 there have also been a few unidentified gulls which I am still puzzling over... Karl Bardon ---- Join or Leave mou-net:http://lists.umn.edu/cgi-bin/wa?SUBED1=mou-net Archives:http://lists.umn.edu/archives/mou-net.html