Invasion
Invasion Description
1st Record: Norway/Norwegian Sea (1946, Hopkins 2002). Dates of reported first records vary. 'Thus, while the official earliest record of this subspecies in Norway is 1952 (Silva 1955), it is likely to have invaded before that, and possibly as early as 1895 (Silva 1957, Norwegian Biodiversity Information Centre 2012).' (Armitage et al. 2014).
Geographic Extent
1st Record: Norway/Norwegian Sea (1946, Hopkins 2002); north to 70 N/Norway/Norwegian Sea (Stetlander 1969, cited by Armitage et al. 2014); Shetland Islands/Scotland/Norwegian Sea (2012, Collin et al. 2015, 8 sites); islands and fjords near Bergen/Norway/Norwegian Sea (Armitage et al. 2014, Armitage and Sjøtun 2016, Armitage et al. 2017, increasing after milder winters, 60° 04? N, 005° 13? E to 60° 16? N, 005° 13? E; ), north to Bodo/Norway/Norwegian Sea, 63.75801, 8.90768 (Armitage and Sjotun 2016
Vectors
| Level | Vector |
|---|---|
| Alternate | Hull Fouling |
| Alternate | Fisheries Accidental (not Oyster) |
| Alternate | Natural Dispersal |
Regional Impacts
| Ecological Impact | Competition | |
| Codium fragile competes for space with the native brown seaweed Fucus serratus, but only in the lower subtidal part of F. serratus' range. Codium fragile tends to replace F. serratus in sheltered subtidal environments, and stony substrate. Fucus serratus is more successful on bedrock, in exposed sites (Armitage and Sjotun 2014). | ||
| Ecological Impact | Habitat Change | |
| Epiphytic and epifaunal communities of the introduced C. fragile, off Norway, shared many species with the native Fucus serratus but showed statistical differences in composition. Fucus serratus support more sessile fauna, especially bryozoans (Armitage and Sjotun 2016). | ||