The effect of organic pollution on local distribution of Nereis diversicolor and Corophium volutator
Esselink, P.; van Belkum, J.; Essink, K. (1989). The effect of organic pollution on local distribution of Nereis diversicolor and Corophium volutator. Neth. J. Sea Res. 23(3): 323-332
In: Netherlands Journal of Sea Research. Netherlands Institute for Sea Research (NIOZ): Groningen; Den Burg. ISSN 0077-7579; e-ISSN 1873-1406, more
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Authors | | Top |
- Esselink, P.
- van Belkum, J.
- Essink, K., more
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Abstract |
Distribution patterns of Nereis diversicolor and Corophium volutator in the SE-Dollard, a 92 km² tidal flat area in the NE Netherlands are described. Body condition as well as the maximal size of juvenile worms correlated positively with elevation of the mudflat, probably caused by a better food supply on the higher mudflats. No spatial variation in size was found for C. volutator. N. diversicolor disappeared from ~1 km² of the intertidal mudflats in the autumn of 1985 as a consequence of the seasonal waste discharges, whereas C. volutator disappeared from an area of ~ 4 km². Though the discharges decreased by almost 50% from 1982 to 1985, N. diversicolor disappeared from about the same area in the 2 years. N. diversicolor is the main prey species of the avocet Recurvirostra avosetta, large flocks of which stay in the Dollard during autumn migration. Though the avocets lost ~30% of their potential feeding area in the Dollard in the 1970s because of the high waste discharges, against only 5 to 10% in 1982 and thereafter (at significant lower discharges), the numbers of the avocets did not respond to the decrease of the discharges. |
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