|Distribution and life cycle of the North American spionid polychaete Marenzelleria viridis (Verrill, 1873) in the Ems estuary|
Essink, K.; Kleef, H.L. (1993). Distribution and life cycle of the North American spionid polychaete Marenzelleria viridis (Verrill, 1873) in the Ems estuary. Neth. J. Aquat. Ecol. 27: 237-246
In: Netherlands Journal of Aquatic Ecology. Kluwer Academic Publishers/Netherlands Society of Aquatic Ecology: Bilthoven. ISSN 1380-8427, more
|Also published as |
- Essink, K.; Kleef, H.L. (1993). Distribution and life cycle of the North American spionid polychaete Marenzelleria viridis (Verrill, 1873) in the Ems estuary, in: Meire, P. et al. (Ed.) Marine and Estuarine Gradients: ECSA 21: Proceedings of the 21st Symposium of the Estuarine and Coastal Sciences Association held in Gent, 9-14 september 1991. Netherlands Journal of Aquatic Ecology, 27(2-4): pp. 237-246, more
|Authors|| || Top |
- Essink, K., more
- Kleef, H.L.
In 1983 the first specimens of the North American spionid polychaete Marenzelleria viridis were found along the European mainland shore in the Ems estuary. Since then, this polychaete has spread over several estuaries around the North Sea and the Baltic. In the inner part of the Ems estuary juveniles were predominantly present in muddy sediments high in the intertidal zone; in more sandy sediments at higher salinities juveniles and adults co-occured. Detailed information was obtained at a muddy and at a sandy station. Gametes were present in the coelomic fluid from November through March. In May new recruits were found in the sediment samples, reaching densities of over 105 m-2 at the muddy station, and c. 2000 m-2 at the sandy station. During summer, densities decreased at the muddy station, coinciding with a density increase at the sandy station, suggesting migration of juveniles from a nursery to the adult habitat. Gage experiments showed that the decrease of juveniles at the muddy station could be attributed to migration and not to mortality due to predation. At the sandy habitat palps and anterior parts of M. viridis made up 4-11% of the stomach content of juvenile plaice (Pleuronectes platessa). In juvenile flounder (Platichthys flesus) only in April c.10% of the stomach content consisted of M. viridis. During 1983-1990 increasing densities of M. viridis at the sandy habitat coincided with a reduced abundance of Nereis diversicolor; however, this inverse relationship was not found to be statistically significant. Density fluctuations of M. viridis and Corophium volutator showed a significant positive relationship, the cause of which is not yet understood.