Larus canusmew gull(Also: common gull)

Geographic Range

Larus canus, the Mew Gull, has a range that spans throughout the Northern Hemisphere. It is found in Europe, Asia, North Africa and North America. (Bent, 1963; Felix, 1998)

Habitat

Mew gulls flourish in and along coastal ranges, tidal estuaries, interior lakes and marshy grasslands. (Bent, 1963)

Physical Description

Mew gulls have an average length of 40 cm (1.3 ft.), with slender, yellowish-green legs and webbed feet. Male and Female gulls have a similar appearance, although males usually are a bit larger. They have gray wings and back with a plain white head and a greenish-yellow bill. The wingspan is usually around 119 to 122 cm (47 to 48 in.). Young gulls plummage is brown and spotted with tan; their beak is dark with a pink undertone. They will not develop adult coloration until about 27 months. (Felix, 1998; Del Hoya, 1996)

  • Range mass
    290 to 552 g
    10.22 to 19.45 oz
  • Average mass
    432 g
    15.22 oz
  • Range length
    40 to 46 cm
    15.75 to 18.11 in
  • Range wingspan
    119 to 122 cm
    46.85 to 48.03 in
  • Average basal metabolic rate
    2.257 W
    AnAge

Reproduction

Breeding among Mew Gulls occurs in colonies on the coasts of Scandinavia, Finland, Russia, Great Britain, Ireland, Denmark, Poland, Germany, Alaska, northwest Canada and on occasion, Holland and France. They are usually already paired when they arrive in March and early April at the breeding grounds. During the initial courtship the female will make primary contact, begging the male for food in a crouched posture. They will generally create large nests, which are almost entirely constructed by the female, while the male keeps his distance, occasionally bringing building materials. The nest itself will be made up of many different materials, such as seaweed, twigs, mosses, bark, grasses, and weed stalks.Mew Gulls tend to build their nests on bare rocks or hummocks.(Bent, 1963; Harrison, 1983; Royal BC Museum, 1995; USGS, 2001; Ehrlich, Dobkin & Wheye, 1988)

Mew Gull eggs are a light brown/olive with brown markings, and are about 57 mm(2.2in) in length. They are laid in March and early April during the breeding season. The female gull will lay her first egg at anytime during a 24 hour period, but the majority of 2nd and 3rd eggs are laid from midday to evening. The eggs are incubated by both sexes at intervals of two to three hours, and will begin to hatch at around three to four weeks. When the chicks are hatched, they are tended by both parents. For the first four days, they will feed the hatchlings insects and small fish. At 20 days the young will begin to forage for food on their own, feeding on insects and their larvae, although they will still occasionally be fed by the parents, and will not be fully independent until about eight weeks.

The young gulls will stay in the nest until near to full growth, all the while being camoflouged by thick, speckled down. However, because many young gulls will often cannibalise their younger or weaker siblings, it is a rarity for more than one chick to survive.(Time Life, 1976; Skutch, 1976; Felix, 1998; Bent, 1963; Ehrlich, Dobkin & Wheye 1988)

  • Breeding season
    March and early April
  • Range eggs per season
    3 to 5
  • Average eggs per season
    3
  • Average eggs per season
    3
    AnAge
  • Average time to hatching
    25 days
  • Average time to hatching
    23 days
    AnAge
  • Average fledging age
    35 days

Lifespan/Longevity

Lifespan of up to 24 years.

Behavior

Mew Gulls will not stray far from land and are known to seek the shore first in the occurrence of stormy weather. The gulls will also advance further inland in large flocks, into agricultural districts, to feast on the exposed worms and larvae after the land has been plowed. Northern gulls will migrate south when breeding season begins. (Bent, 1963)

Communication and Perception

Food Habits

Mew gulls can be quite opportunistic, which certainly contributes to their adeptness at survival and their great abundance. As an example, the Mew gull, when it is able to get a clam or muscle, will fly over and drop the creature repeatedly on a hard surface until the shell gives way and cracks open. However the Mew gulls food of choice is almost always fish or seafood, which it will catch by dipping down into the water, or simply floating above and waiting for the fish. Worms, insects, mice, berries and grains from farmlands also make up the wide spectrum of food gulls will consume. Many times when food is scarce, gulls will resort to cannibalism, eating a large number of hatchlings and younger birds, which in many gull colonies leads to a high infant mortality rate.

Foods eaten include: cod, herring, worms, insects, berries, grains, crustaceans, clams, mussels and young sea birds.

(Time Life, 1976; Bent, 1963; Harrison, 1983)

  • Animal Foods
  • birds
  • mammals
  • fish
  • eggs
  • carrion
  • insects
  • mollusks
  • terrestrial worms
  • aquatic crustaceans
  • Plant Foods
  • seeds, grains, and nuts
  • fruit

Predation

Cannibalistic adult gulls will eat eggs and hatchlings. Also, mammals such as foxes and weasels may at times kill more than they can eat at one time (Time Life, 1976; Ehrlich, Dobkin & Wheye 1988)

Ecosystem Roles

Mew Gulls, as with their many relatives, are known as efficient garbage collectors. They scavenge off dead animals washed ashore and human debris left behind, in effect, keeping their habitat somewhat clean. (Time Life, 1976)

  • Ecosystem Impact
  • disperses seeds

Economic Importance for Humans: Positive

Mew Gulls, along with many other types of gulls, have helped to keep beaches a bit cleaner due to their scavenging nature. This in effect, cuts the cost of maintenance of beaches. (Time Life, 1976)

Economic Importance for Humans: Negative

In some areas the gulls become too numerous and cause problems, such as crashing into planes, defecating on buildings and statues, and crowding out other species of birds from their habitats. (Time Life, 1976)

Conservation Status

In some areas they are protected by law for their esteemed ability to keep beaches and coastal waters relatively clean of natural and human debris. (Time Life, 1976)

Contributors

Alex Steele (author), Fresno City College, Carl Johansson (editor), Fresno City College.

Glossary

Arctic Ocean

the body of water between Europe, Asia, and North America which occurs mostly north of the Arctic circle.

Atlantic Ocean

the body of water between Africa, Europe, the southern ocean (above 60 degrees south latitude), and the western hemisphere. It is the second largest ocean in the world after the Pacific Ocean.

World Map

Nearctic

living in the Nearctic biogeographic province, the northern part of the New World. This includes Greenland, the Canadian Arctic islands, and all of the North American as far south as the highlands of central Mexico.

World Map

Pacific Ocean

body of water between the southern ocean (above 60 degrees south latitude), Australia, Asia, and the western hemisphere. This is the world's largest ocean, covering about 28% of the world's surface.

World Map

Palearctic

living in the northern part of the Old World. In otherwords, Europe and Asia and northern Africa.

World Map

acoustic

uses sound to communicate

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.

bog

a wetland area rich in accumulated plant material and with acidic soils surrounding a body of open water. Bogs have a flora dominated by sedges, heaths, and sphagnum.

carrion

flesh of dead animals.

chemical

uses smells or other chemicals to communicate

colonial

used loosely to describe any group of organisms living together or in close proximity to each other - for example nesting shorebirds that live in large colonies. More specifically refers to a group of organisms in which members act as specialized subunits (a continuous, modular society) - as in clonal organisms.

endothermic

animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.

female parental care

parental care is carried out by females

freshwater

mainly lives in water that is not salty.

iteroparous

offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).

male parental care

parental care is carried out by males

marsh

marshes are wetland areas often dominated by grasses and reeds.

migratory

makes seasonal movements between breeding and wintering grounds

monogamous

Having one mate at a time.

motile

having the capacity to move from one place to another.

native range

the area in which the animal is naturally found, the region in which it is endemic.

oceanic islands

islands that are not part of continental shelf areas, they are not, and have never been, connected to a continental land mass, most typically these are volcanic islands.

omnivore

an animal that mainly eats all kinds of things, including plants and animals

oviparous

reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.

saltwater or marine

mainly lives in oceans, seas, or other bodies of salt water.

seasonal breeding

breeding is confined to a particular season

sexual

reproduction that includes combining the genetic contribution of two individuals, a male and a female

swamp

a wetland area that may be permanently or intermittently covered in water, often dominated by woody vegetation.

tactile

uses touch to communicate

visual

uses sight to communicate

young precocial

young are relatively well-developed when born

References

Bent, A. 1963. Life Histories of North American Gulls and Terns. New York, Ny: Dover Publications, Inc..

Burton, R. 1985. Bird Behavior. New York: Alfred A. Knopp Inc..

Del Hoya, J., A. Elliott, J. Sargatal. 1996. Handbook of the Birds of the World. Barcelona: Lynx Edicions.

Ehrlich, P., D. Dobkin, D. Wheye. 1988. The Birder's Handbook: A Field Guide To The Natural History of North American Birds. New York: Simon & Schuster Inc..

Felix, J. 1998. The Illustrated Book of Birds. Aventinum Nakladatelstvi: Caxton Editions.

Harrison, C., A. Greensmith. 1993. Birds of the World. New York, NY: DK Publishing.

Harrison, P. 1983. Seabirds, and Identification Guid. Boston: Houghton Mifflin Company.

Royal British Columbia Museum, 1995. "Royal BC Museum" (On-line). Accessed October 12, 2001 at http://rbcm1.rbcm.gov.bc.ca/nh_papers/gracebell/english/mew_gull.html.

Skutch, A. 1976. Parent Birds and their Young. Texas: University of Texas Press.

Small, A. 1994. California Birds: Their status and distribution. New York: Ibis Publishing Company.

TimeLife, 1976. Wild, Wild World of Animals: Birds of sea, shore, & stream. New York: TimeLife.

USGS, 2001. "Mew Gull" (On-line). Accessed October 12, 2001 at http://www.mbr-pwrc.usgs.gov/id/framlst/i0550id.html.