The distribution of japweed - Sargassum muticum - in Sweden 1996
Abstract: The arrival of the brown alga Sargassum muticum and the subsequent expansion at the Swedish west coast represents one of the most dramatic changes in the upper sublittoral during this century. In the present study sampling areas visited in 1993 together with some new, were revisited to obtain data of the current population status. Attached populations of S. muticum were found from the Norwegian border to the middle part of the province of Halland. The number of populations and population sizes decrease when going south. However, the number of new sites, as well as population numbers still increase. Continuous populations are common in the northern part of the county of Bohuslän, and isolated localities can now be found in the inner parts of the archipelagoes. Localities, showing high population numbers as well as very tall (to 4 m) and wide plants, were recorded close to the Ringhals nuclear power plant, Halland. No morphological differences were seen between plants from the more saline Skagerrak and the more brackish Kattegat.
Contact person(s): Jan Karlsson
Grants: World Wide Fund for Nature (WWF).
Collaboration: Lars-Ove Loo, Dept. of Marine Ecology (TMBL), Göteborg University.
Report (In Swedish only) available in