BIOTIC

BIOTIC Species Information for Ascophyllum nodosum
All Taxonomy Biology Distribution Reproduction

Researched by	Jacqueline Hill & Nicola White	Data supplied by	MarLIN
Refereed by	Dr Dagmar Stengel
Distribution and Habitat
Distribution in Britain & Ireland	All coasts of Britain and Ireland.
Global distribution	Global distribution is restricted to the North Atlantic Ocean. Its northern limits are the White Sea in the east and Baffin Island in the west. Southern distributions extend to northern Portugal and New Jersey.
Biogeographic range	Not researched	Depth range	Not relevant
Migratory	Non-migratory / Resident
Distribution Additional Information	The local distribution of Ascophyllum nodosum is largely determined by wave exposure. As exposure to wave action increases the number of plants becomes progressively less and they consist increasingly of stumps and short lived shoots. On sheltered shores Ascophyllum nodosum may competitively exclude %Fucus vesiculosus%. The species can tolerate salinities down to 15 psu and can tolerate constant immersion but thrives better when exposed to air at low tide.

Substratum preferences	Small boulders Cobbles Bedrock Large to very large boulders	Physiographic preferences	Strait / sound Sealoch Ria / Voe Open coast Estuary
Biological zone	Mid Eulittoral Upper Eulittoral	Wave exposure	Moderately Exposed Sheltered Very Sheltered Extremely Sheltered Ultra Sheltered
Tidal stream strength/Water flow	Strong (3-6 kn) Moderately Strong (1-3 kn) Weak (<1 kn) Very Weak (negligible)	Salinity	Full (30-40 psu) Variable (18-40 psu) Reduced (18-30 psu)
Habitat Preferences Additional Information
Distribution References	Baardseth, 1970, Peckol, 1988, Hardy & Guiry, 2003,