Five species of gull commonly occur in the United Kingdom, but only 3, the Greater Black-Backed (Larus marinus), the Lesser Black-Backed (Larus fuscus) and the Herring Gull (Larus argentatus) are regarded as pests and can be killed under the General Licence.
 
 
Food and Habits
 
In inland localities, especially outside the breeding season, gulls often roost in many thousands on large bodies of water such as reserviors or flooded gravel pits. When inland, are largely dependent on domestic refuse for food. Herring gulls and lesser black-backed gulls are becoming increasingly important pests as they have changed their behaviour over the last 20 years, to nest more and more on buildings.
 
Heavy fouling may occur on buildings used by gulls. They can also damage roofs by pecking, their nests can block drainage channels and chimneys and their aggressive behaviour during the breeding season can result in attacks on nearby humans. They will take birds in attacks on nearby humans. They will take birds and small mammals for food.
 
Breeding and Life Cycle
 
These birds have a distinct breeding season, between May and August in Northern Europe. The Herring Gull starts breeding when 5 years old and will live for up to 25 years. Normally two eggs are laid per season, but if the eggs are removed or are killed, they can relay several times that season. Nests are usually made alongside other gulls in colonies and once a breeding site is established, the gulls will return to it year after year. The numbers of breeding pairs on roofs in the UK is increasing at a rate of 10% per year for Herring Gulls and 17% per year for Lesser Black-Backed Gulls.
 
PEST SPECIES

Great B.B. Gull

Lesser B.B. Gull

Herring Gull
 

PROTECTED SPECIES

Black-Headed Gull

Common Gull Kittiwake
 

The principal feature to easily distinguish the pest gulls from the protected ones (in the UK) is the size.
 

Big gulls (more than 50cm in length) are likely to be pests
- little ones should be left alone.