Food availability and predator presence in a coastal nursery area of the brown shrimp (Crangon crangon)
Boddeke, R.; Driessen, G.; Doesburg, W.; Ramaekers, G. (1986). Food availability and predator presence in a coastal nursery area of the brown shrimp (Crangon crangon), in: Muus, K. (Ed.) Proceedings of the 20th European Marine Biology Symposium: Nutrient Cycling. Processes in Marine Sediments, Hirtshals, Denmark, 9-13 September 1985. Ophelia: International Journal of Marine Biology, 26: pp. 77-90 In: Muus, K. (Ed.) (1986). Proceedings of the 20th European Marine Biology Symposium: Nutrient Cycling. Processes in Marine Sediments, Hirtshals, Denmark, 9-13 September 1985. European Marine Biology Symposia, 20. Ophelia: International Journal of Marine Biology, 26. ISBN 87-981066-4-3. 477 pp., more In: European Marine Biology Symposia., more |
Authors | | Top | - Boddeke, R.
- Driessen, G.
- Doesburg, W.
- Ramaekers, G.
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Abstract | Along the marine, sandy coast of the Netherlands between Wassenaar and Egmond, large recruitment to the adult stock of Crangon crangon occurs annually in September-November. This recruitment is the result of settlement in this area of postlarval C. crangon in late May-July. This short and sharply defined period of settlement contrasts with the situation in Dutch estuarine nursery areas, where large-scale settlement occurs in April-October. The coastal zone Wassenaar-Egmond is strongly eutrophicated by river water sluiced at Hook of Holland. The settlement of C. crangon is linked with a bloom of calanoid copepods in May-July. Calanoid copepods are here the major food item for C. crangon of 10-20 mm and these pelagic organisms form a practically unlimited food supply for bottom-dwelling shrimps. Predation on juvenile C. crangon is light in May-July, because predation by 0-group fish becomes significant not earlier than August. Due to the unlimited food supply and low level of predation, recruitment to the adult stock in autumn depends to a large extent on the abundance of ripe eggs in this area in May-July. In 1978-84, the yield of ripe eggs stayed constant until densities at least five times higher than the observed minimum level. |
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