Reële kans op vestiging? |
Ja |
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Betrouwbaarheid beoordeling |
Grote mate van zekerheid (meerdere bronnen) |
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Vestigingsstatus |
Gevestigd |
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Zeldzaamheid |
Algemeen |
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Invasiviteit |
Niet invasief |
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Invasiviteit (toelichting) |
B. imbricata ranges in the Western Atlantic from the USA to Argentina. In the Eastern Atlantic it occurs from the Barents Sea to the Mediterranean Sea (and probably also in the Black and Caspian Seas, although this may concern a different species (Hayward 1985, Wolff 2005). It is known from both temperate and sub-tropical waters. Being often considered an invasive exotic species, it could easily be considered native to Europe as well. Den Hartog & Van der Velde (1987) consider the Dutch species of the genus Bowerbankia to be introduced, but do not explain why. Wolff (2005) seems to have doubts: ‘B. imbricata is perhaps an exotic non-indigenous species’. Faasse (website cryptosula.nl) does consider B. imbricata native (as he does B. gracilis). De Blauwe also does not consider B. imbricata exotic, as could be ascertained by remarks on www.werkgroepexoten.nl. Outside the Netherlands the main sustrata seems to be marine brown algae (Hayward, 1985). Thus it may be transported naturally, on floating weeds. If it is introduced, it probably arrived to Europe on ships’ hulls (Wolff, 2005). |
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Type introductie |
Niet opzettelijk |
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Jaar van eerste melding |
1859 |
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Natuurlijke verspreiding |
Onbekend |
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Verspreiding in Nederland |
Noord-Holland |
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Zeeland |
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Verspreiding in Nederland (toelichting) |
B. imbricata probably occurs in the Netherlands for at least 150 years, as it is mentioned for the Dutch fauna by Herklots (1859; without locality). In the Dutch waters the species is usually found at localities with reduced salinity (brackish water; De Blauwe 2005; Faasse & De Blauwe 2004). It is fairly common in the estuaries of the Delta area and was also present in the Grevelingen (now Lake Grevelingen) before it was closed offf from the sea (Heerenbout 1970). Colonies often settle on marine brown algae, stones, wood and other organisms. The species is fairly common in the Eastern Scheldt and in brackish channels (Kanaal door Goes; Kanaal door Zuid-beveland: Faasse 1993). It has also been found in the Wadden Sea (Texel, veerhaven: Mulder 1983). |
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Habitats |
Mariene habitats |
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Estuaria en brakwatergebieden |
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Wijze van introductie |
Aangroei op scheepsrompen |
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Ecologische impact (toelichting) |
The species often lives on, or is associated with other sessile organisms, for instance Hydroids and other Bryozoa. It might compete with these for space and resources, but there are no data of any ecological impact in the Netherlands. |
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Economische impact (toelichting) |
As there are no data on any ecological impact, there are none on the economic impact either. |
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