BIOTIC

BIOTIC Species Information for Alaria esculenta
All Taxonomy Biology Distribution Reproduction

Researched by	Dr Harvey Tyler-Walters	Data supplied by	MarLIN
Refereed by	Dr Stefan Kraan
Distribution and Habitat
Distribution in Britain & Ireland	Found around the Shetland Isles, Orkney and east coast of Scotland, south to Flamborough Head in England. Its distribution continues along the south west of England and the west coasts of England, Wales, Scotland and Ireland including the Isle of Man.
Global distribution	Alaria esculenta occurs in the North Atlantic from Novaya Zemlya to Iceland and south to Brittany in the east and from the shores of Greenland to the Bering Strait in the west. It also occurs in the Bering Sea and Sea of Japan in the North Pacific
Biogeographic range	Not researched	Depth range	0-8 m
Migratory	Non-migratory / Resident
Distribution Additional Information	Alaria esculenta is absent from most of the east coast of England, primarily due to a lack of suitable substrata. The species is found all around the Irish coast, where rocky shores as substratum are available. It occurs at a depth of 15 m in the Aran Islands and below 35 m off the Scellig Islands, Ireland and Rockall. Alaria esculenta is present in the North Pacific and North Atlantic, where it is located north as far as the winter sea ice and as far south as the 16 °C summer isotherm, represented by the French coast of Brittany in the European North Atlantic (Luning, 1990). Its absence in the southern North Sea and English Channel is due to high summer surface temperatures of 16 °C, which it cannot survive (Munda & Luning, 1977; Widdowson, 1971; Sundene, 1962). Its distribution in the Arctic Sea is associated with the -2 °C February winter isotherm (Kraan pers. comm.).

Substratum preferences	Bedrock Large to very large boulders Small boulders Cobbles Pebbles Artificial (e.g. metal/wood/concrete)	Physiographic preferences	Open coast Sealoch
Biological zone	Lower Eulittoral Upper Infralittoral Sublittoral Fringe	Wave exposure	Extremely Exposed Very Exposed Exposed
Tidal stream strength/Water flow	Strong (3-6 kn) Moderately Strong (1-3 kn) Weak (<1 kn)	Salinity	Full (30-40 psu)
Habitat Preferences Additional Information
Distribution References	Fish & Fish, 1996, Hayward et al., 1996, Birkett et al., 1998b, Lüning, 1990, Guiry, 2000, Sundene, 1962, Dring, 1982, JNCC, 1999, Picton & Costello, 1998, Kraan & Guiry, 2000, Munda & Luning, 1977, Newton, 1931, Hardy & Guiry, 2003,