Black Legged Kittiwakes

Rissa tridactyla

A medium-sized gull with a maximum body length of 42 centimetres. Their wingspan can measure 95 to 120 centimetres. Their main body colour is white with a grey back and black legs. Wingtips are black. Juveniles will have a black bill which changes to yellow in adults. Juveniles also have a distinctive "M" shape across their upper wings.

Authority

Linnaeus, 1758

Classification Details

Phylum: Chordata (chordates); Subphylum: Vertebrata (vertebrates); Class: Aves (birds).

Habitat

These birds colonize rocky coasts during their breeding season. In North America, the majority breed in the Canadian high Arctic, the Gulf of St. Lawrence, and around Newfoundland. There are also small colonies in Nova Scotia and the Bay of Fundy. They are at sea for the rest of the year and range widely across the Atlantic and Pacific Oceans.

Diet

Observed feeding at the surface of the water, often in large flocks. They may make shallow plunge dives down to depths of around one metre or seize prey from the surface of the water. They eat small fish, molluscs, crustaceans such as amphipods and krill, and discards from fishing boats.

Reproduction

Sexes are separate. They reach sexual maturity between the ages of three to eight years, after which they nest in colonies. Pairs may return to the same nest site and previous partner. They create their nests from seaweed, feathers, and barnacles on narrow cliff ledges. Kittiwakes lay two eggs at a time. They incubate their eggs for 23 to 32 days with both parents taking turns. The grey, down-covered chicks can move on their own immediately after hatching. Parents brood chicks for around eight days but leave them for longer periods after that. Both parents feed the chicks with regurgitated food. Chicks leave the nest when they are around 35 days old.

Fun Facts

Kittiwakes nest on narrower ledges than other seabirds. Some of these may be only 10 centimetres wide. Birds in nests face in towards the cliff with their tails hanging over the edge.

References

Kehoe FP and Diamond T (2001) Increases and expansion of the New Brunswick breeding population of Black–legged Kittiwakes, Rissa tridactyla. Canadian Field Naturalist 115, 349–350.

Hatch SA, Robertson GJ and Baird PH (2009). Black-legged Kittiwake (Rissa tridactyla), version 2.0. In The Birds of North America (A. F. Poole, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bna.92

Sweet NA (2008) Rissa tridactyla Black-legged kittiwake. In Tyler-Walters H. and Hiscock K. (eds) Marine Life Information Network: Biology and Sensitivity Key Information Reviews, [on-line]. Plymouth: Marine Biological Association of the United Kingdom. Available from: https://www.marlin.ac.uk/species/detail/2218 Accessed online 22 January 2020.

Wooller RD and Coulson JC (1977) Factors affecting the age of first breeding of the kittiwake Rissa tridactyla. International Journal of Avian Science 119(3), 339–349.

World Register of Marine Species (2020) Rissa tridactyla (Linnaeus, 1758) – WoRMS Taxon Details. http://www.marinespecies.org/aphia.php?p=taxdetails&id=137156 Accessed online 22 January 2020.

USGS. Black-legged kittiwake Rissa tridactyla. https://www.mbr-pwrc.usgs.gov/id/framlst/i0400id.html Accessed online 22 January 2020.

Van Guelpen L, Pohle G, Vanden Berghe E and Costello MJ (2005) Marine Species Registers for the North Atlantic Ocean. World Wide Web electronic publication. http://www.vliz.be/vmdcdata/narms/