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The predation impact of juvenile herring Clupea harengus and sprat Sprattus sprattus on estuarine zooplankton

Maes, J. and Tackx, M. and Soetaert, K.E.R. (2005) The predation impact of juvenile herring Clupea harengus and sprat Sprattus sprattus on estuarine zooplankton. Hydrobiologia, 540, 225-235. ISSN 0018-8158.

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Official URL: http://dx.doi.org/10.1007/s10750-004-7146-3

Abstract

The consumption of estuarine copepods by juvenile herring and sprat during estuarine residency was estimated using fish biomass data and daily rations calculated from two models of feeding in fish: a bioenergetic model and a gastric evacuation model. The bioenergetic model predicted daily rations that were, on average, three times higher than those estimated by a model based on field records of stomach contents. The biomass of herring and sprat in the estuary was negatively correlated with the daily ration suggesting that the clupeid fish populations were resource-limited. Copepod production decreased towards the winter and peaked in spring and summer. The relative importance of predation changed seasonally in function of the migration pattern of herring and sprat. In the spring and the summer, in situ production ofcopepod biomass was higher than the in situ consumption by fish. During the fall and the winter, consumption exceeded production. This suggests that top–down control exerted by marine pelagic fish may be an important force structuring estuarine copepod populations. [KEYWORDS: top–down control ; predation ; consumption ; production ; herring ; sprat ; calanoid copepods ; estuary ; Eurytemora affinis ; Acartia tonsa]

Item Type:Article
Institutes:Nederlands Instituut voor Ecologie (NIOO)
ID Code:11744
Deposited On:23 Nov 2011 01:00
Last Modified:31 Mar 2014 10:13

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