At this time of year I rarely see any Herring or black backed gulls at the Gloucester and Sharpness Canal its all the small Black headed gulls every time I go every year. I visit during spring and summer aswell as Autumn and winter so I visit a lot sometimes year round to watch and take pictures. But I usually see Herring gulls and black backed gulls in Spring and Summer. It’s very interesting that the the Herring gulls and black backed gulls disappear from the canal during Autumn and Winter every year and then are abundant at the canal again during Spring and Summer and since people throw food for the birds at the canal you would think the herring gulls and black backed will come and join the frenzy with the black headed gulls and that it would attract them but when people do feed them or even drop anything the herring gulls and black backed dont show up. it’s almost like they have found more abundant food than there somewhere else and that might be one of the reasons the herring gulls and black backed are most abundant there during the Spring and Summer months and not Autumn and winter.