Species Regional Summary
Amphibalanus improvisus
None ( B-XII )

Vectors

Level	Vector
Alternate	Hull Fouling
Alternate	Natural Dispersal
Alternate	Ballast Water

Regional Impacts

Economic Impact		Industry
In the Baltic Sea, where it is the only barnacle species present, A. improvisus is reported to contribute to hull fouling of ships and the fouling of power plants (Vuorinen et al. 1986). Costs of fouling of power plants in Swedish waters were estimated at 10-38 SK (=1.5-5.5 million dollars) per year (Gren et al. 2009).
Economic Impact		Shipping/Boating
In the Baltic Sea, where it is the only barnacle species present, A. improvisus is reported to contribute to hull fouling of ships and the fouling of power plants (Vuorinen et al. 1986). Costs of fouling of recreational boats in Swedish waters, due to A. improvisus were estimated at 122-331 million Swedish kroner, SK, equal to 8-49 million dollars, per year. Fouling of commercial vessels was estimated at 33-49 SK, equal to 5-7 million dollars, per year, for a total cost of 23-56 million dollars per year (Gren et al. 2009).
Ecological Impact		Habitat Change
In the Gulf of Bothnia, A. improvisus was classified as having some habitat impacts, by fouling eelgrass and algae (Bostrom and Bonsdorff 1997 and Raberg and Kautsky 2007, cited by Zaiko et al. 2011).

References

Gren, Ing-Marie; Isacs, Lina; Carlsson, Mattias (2009) Costs of alien invasive species in Sweden, Ambio 38(3): 135-140

Leppakoski, Erkki; Olenin, Sergei (2000) Non-native species and rates of spread: lessons from the brackish Baltic Sea., Biological Invasions 2: 151-163

Vuorinen, Ilppo; Laihonen, Pasi; Lietzén, Erkki (1986) Distribution and abundance of invertebrates causing fouling in power plants on the Finnish coast, Memoranda Societatis pro Fauna et Flora Fennica 62: 123-125

Zaiko, Anastasija; Lehtiniemi, Maiju; Narscius, Aleksas; Olenin, Sergej (2011) Assessment of bioinvasion impacts on a regional scale: a comparative approach, Biological Invasions 13: 1739-1765

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