Great Black-backed Gulls

An adult Great Black-backed Gull, Larus marinus. They are called great black backs for short, or just black backs.  Click to enlarge. 

I saw a flock of great black backs on the beach at Cape Henlopen Point State Park in Lewes, Delaware, a few weeks ago. They are the largest gulls in the world. Adults are about 30 inches long with a wingspan of about five feet. They have pink legs and a yellow bill that has a red dot on it near the tip. The adult in the picture above is in non-breeding plumage with faint streaking on the head; when breeding the head is pure white. The bird's size and dark colored back and upper wings make it easy to identify.

The brown checkered plumage of the bird in the center identifies him as a juvenile. He was born this year and is still wearing his first set of feathers. His bill is black. His legs are pink.  

The bird in the center, above, is also immature but changing from  the juvenile state  into his first winter plumage, which is a bit darker and shows some pink at the base of the bill. He is hiding his pink legs. Great black backs take four years to achieve their adult plumage, passing through summer and winter outfits every year until then.  

I walked all the way around the point from harbor side to ocean side. I recommend it. Click here for directions and information. There are two lighthouses!

Delaware Breakwater Light. 

Harbor of Refuge Lighthouse.