Bonnemaisonia hamifera

Division: Rhodophyta
Class: Rhodophyceae
Order: Bonnemaisoniales
Species name: Bonnemaisonia hamifera Hariot
Synonyms: Trailliella intricata Batt. (part of life cycle)
Common name: None
Date of introduction and origin
Bonnemaisonia hamifera was first found in Falmouth, Cornwall, and Studland, Dorset, in 1893 (Holmes 1897) although the tetrasporangial phase Trailliella was first collected from Dorset in 1890 (Farnham 1980). This species originates in the Pacific and was probably introduced from Japan.
Method of introduction
The exact method is unknown but it is considered to have been introduced unintentionally with shellfish (I. Tittley pers. comm.).
Reasons for success
Lack of grazers, rapid growth rate, and its opportunistic qualities have contributed to its success.
Rate of spread and methods involved
This species has spread from Cornwall in 1893 to the Orkney Islands by 1929, and Shetland by 1949 by both marginal (up to 30 miles) and remote (beyond 30 miles) dispersal. It was found in Norway in 1916 and the Faroes in 1980.
This species is distributed throughout the British Isles, although is uncommon on the east coast. In Europe it is found from Norway to the Azores including Ireland (Irvine 1982; South & Tittley 1986; Westbrook 1930).
Factors likely to influence spread and distribution
It is restricted in Britain by cold temperatures and the temperature required for reproduction.
Effects on the environment
Effects on commercial interests
Control methods used and effectiveness
None used.
Beneficial effects
None known.
There are two macroscopic phases to the life of this species, the filamentous Trailliella "pink cotton wool" phase being very difficult to distinguish from the same life phase of related species (D.A. Birkett pers. comm.).
Farnham, W.F. 1980. Studies on aliens in the marine flora of southern England. In: The shore environment, volume 2: ccosystems, ed. by J.H. Price, D.E.G. Irvine & W.F. Farnham, 875-914. London, Academic Press. (Systematics Association Special Volume, No. 17B.)
Holmes, E.M. 1897. Note on Bonnemaisonia hamifera. Journal of Botany, London, 35: 408-409.
Irvine, D.E.G. 1982. Seaweeds of the Faroes. 1: the flora. Bulletin of the British Museum (Natural History), Botany Series, 10: 109-131.
South, G.R., & Tittley, I. 1986. A checklist and distributional index of the benthic marine algae of the North Atlantic Ocean. St. Andrews & London, Huntsman Marine Laboratory & British Museum (Natural History).
Westbrook, M.A. 1930. Notes on the distribution of certain marine red algae. Journal of Botany, London, 68: 257-264.
Acknowledgements (contributions from questionnaire)
Mr I. Tittley, Natural History Museum, London.