This is an egg of the Common Gull (Larus canus), a medium-sized gull belonging to the family Laridae (gulls and terns). It is also known in North America as the Mew Gull. This egg specimen exhibits typical characteristics for the species’ clutch. 

Adults typically measure about 40–46 cm in length, with a wingspan of approximately 100–130 cm and a body mass in the region of ~300–480 g. The upperparts (back and wings) are pale grey, while the head and underparts are white. The wingtips are black with small white “mirror” spots. The bill and legs are greenish-yellow, and the eye is dark. In winter plumage, the head may exhibit fine grey streaking and the bill can show a darker tip. Juveniles are mottled brown and take a few years to attain full adult plumage. The call is a high-pitched, mewing or laughing sound, which has contributed to its alternative common name.

Location:
The Common Gull breeds across the cool temperate regions of the Palearctic, from Iceland and northern Europe across to Siberia and the Russian Far East. It favours coastal marshes, inland lakes, river margins and wetland habitats for nesting. During the non-breeding season many birds migrate southward, wintering around western and southern Europe, the Mediterranean basin, and parts of Asia.

Average Size:
Length: ~40–46 cm.
Wingspan: ~100–130 cm.
Weight: ~300–480 g.

Family:
Laridae (gulls and terns)

Species:
Larus canus

Ecological Role:
Common Gulls are omnivorous and opportunistic feeders, consuming fish, marine and freshwater invertebrates, insects, earthworms and scavenged food waste. Their adaptable diet allows them to exploit both natural and human-modified environments, from wetlands and estuaries to farmland and urban areas. They play a role in nutrient cycling and food-web dynamics across coastal and inland ecosystems.

Movement and Behaviour:
This species is gregarious, often found in flocks outside the breeding season. Common Gulls breed colonially but may also nest in loose groups or singly. Nesting typically occurs on the ground in marshes, dunes or near water, though they will occasionally nest on buildings or low trees. Courtship involves calls and displays common to gulls.

Reproduction & Eggs:
Nests are shallow scrapes lined with vegetation. A typical clutch consists of 2–3 eggs, sometimes varying slightly, which are olive-brown or buff with darker blotches and provide camouflage against the substrate. Eggs are incubated by both parents for about 24–26 days. Chicks are precocial (down covered and mobile soon after hatching) and generally fledge at around 30–36 days old, although they may remain dependent on the parents for some time thereafter.

Conservation Status:
The International Union for Conservation of Nature (IUCN) assesses the Common Gull as Least Concern, reflecting a large global population and wide distribution. Despite this stable status, local populations can be affected by habitat loss, disturbance at breeding sites, pollution and changes in food availability.

Collection Information:
Collected in Britain, part of the Marshall-Ware Collection.