|Where exotic mussels Dreissena polymorpha and Mytilopsis leucophaeata meet in the brackish Noordzeekanaal, the Netherlands|
|van der Velde, G.; Van der Gaag, R.; Rajagopal, S.; Jenner, H.A. (1998). Where exotic mussels Dreissena polymorpha and Mytilopsis leucophaeata meet in the brackish Noordzeekanaal, the Netherlands, in: (1998). Abstracts from the 8th International Zebra Mussel and other Nuisance Species Conference, Sacramento California. |
|In: (1998). Abstracts from the 8th International Zebra Mussel and other Nuisance Species Conference, Sacramento California[s.n.][s.l.], more|
Introduced species; Dreissena polymorpha (Pallas, 1771) [WoRMS]; Mytilopsis leucophaeata (Conrad, 1831) [WoRMS]; ANE, Netherlands [gazetteer]; Brackish water
In the Netherlands, the zebra mussel, Dreissena polymorpha (Pallas, 1771) was first recorded in the Haarlemmermeer near Haarlem in 1826. This species was introduced in The Netherlands with transported timber originating from the Eastern Baltic. Furthermore, D. polymorpha spread across Europe, due to the expansion of canal networks. At present, D. polymorpha is one of the most commonly occurring mussel species in the large rivers, lakes and canals of Europe. The brackish water mussel, Mytilopsis leucophaeata (Conrad, 1831) was first recorded in The Netherlands by Maitland in 1895 in the River Amstel near Amsterdam. In Europe, the occurrence of M. leucophaeata was also reported from Belgium, France and Germany. This species was reported to have been introduced by ships originating from (sub)tropical areas of the Atlantic and Gulf coasts of the United States. D. polymorpha and M. leucophaeata are the dominant species in sessile communities of the Noordzeekanaal connecting Amsterdam harbour with the North Sea. The cooling water systems of industrial plants situated in the Noordzeekanaal often experience fouling problems caused by these mussels. Recently, the occurrence of M. leucophaeata has been also reported from freshwater habitats. M. leucophaeata is reported as a euryhaline species. It is unclear, however, what limits the seaward distribution of D. polymorpha and freshwater distribution of M. leucophaeata. We report the results of our studies from October 1989 to September 1990 on the distribution and population structure of D. polymorpha and M. leucophaeata in the Noordzeekanaal related to environmental factors. Ten sampling locations were selected in the Noordzeekanaal from 0 to 28 km distance from the coast. The salinity varied between 1.7 and 9.2%. The maximum densities of D. polymorpha and M. leucophaeata were 2750 and 17000 individuals/m2, respectively. An attempt was made to estimate the influence of salinity on the distribution of D. polymorpha and M. leucophaeata in the Noordzeekanaal.