All As I mentioned in a previous email, I was in Milwaukee the past 3 days at a fish conference. On my way home today, I drove past Northridge lakes around noon. There were a few hundred gulls plus both Canada and snow geese. About half the gulls were on the water and the other half were on land. The on-land group didn't contain anything of interest but there were 2 dark-mantled gulls on the water. One was clearly smaller than the surrounding herring gulls and I took it to be a lesser black-backed gull. However the other one was larger than the majority of the herrings and the same size as the largest of the herrings. It stayed in the water the whole time I was scoping it until something spooked most of the gulls on the water. When it took flight I wasn't able to discern leg color with certainty but I think they were pink. So based on mantle color (slate-colored), size (herring gull size), and likely leg color, I took this to be the slaty-backed.
This bird had lots of smudging between the bill and eye and a little behind the eye. The only photos of the Northridge bird I could find on line were taken the first or second day it was found. The bird I saw seems to match the head pattern of the bird in the photos. However, the photos were fairly distant so if anyone has any better/closer photos, I'd appreciate it if you could send me them for comparative purposes.
Greg Seegert Beaver Dam, until tomorrow when I head to Green Bay to ice fish...he said hopefully