Herring Gull

This large gull has a light gray back, black wingtip, and a white head and stomach. These birds will scour the shoreline looking for scraps on the beach and in the water. They will chase after fishing boats and dumps looking for food to take from other birds. Herring gulls will live in a diverse area from coastal mudflats to fields and garbage dumps. Pairs will scour out several scrapes before they choose the final nesting place in which they lay 1-3 eggs. They will add vegetation, feathers, rope, and other materials to the nest throughout the incubation. The incubation period is 31-32 days and the chicks stay in the nesting area until they fledge. 

Source-
https://www.allaboutbirds.org/guide/Herring_Gull/lifehistory