Seagulls with black heads were about the only kind we saw at the beaches we visited. When I got home, I looked gulls up in my Bird of North America field guide, and I believe that I've identified it as a Laughing Gull. The pictures here were taken at Bethany Beach and Rehoboth Beach on the Atlantic Coast of Delaware. It was so crowed in places that a person had to dodge the umbrellas and beach chairs.