Herring gulls have light grey backs, white under parts and black wing tips. Their legs are pink with webbed feet, they have hooked yellow bills marked with a red spot. Young birds are mottled brown.
This species is closely related to the Herring gull, its main differences are that it is smaller, its back is dark grey and it has yellow legs. Its breeding and behaviour are much the same as the Herring gull, except it migrates in winter. A similar gull to this is the Greater Black Backed gull, they are much larger than the Lesser Black Backed gull, have black backs and pink legs.
These are derived from domestic pigeons that have returned to the wild, originally bred from the wild rock dove which naturally inhabits sea cliffs and mountains. Pigeons breed all year round and can nest up to 6 times a year. They build flimsy nests out of twigs in sheltered areas such as disused buildings and enclosed positions out of the wind. They lay 2 eggs that hatch out after about 20 days, the chicks (squabs) become fledglings after 30 days and can breed after 6 months. Feral pigeons live for roughly 5 years.
The above birds are the most common that we are required to proof against, but on occasion there are other species for which proofing and deterrent systems may be required. These include: