© 2005 International Council for the Exploration of the Sea
Changes in the structure and function of the North Sea fish foodweb, 1973–2000, and the impacts of fishing and climate
Marine Laboratory PO Box 101, Victoria Road, Aberdeen AB11 9DB, Scotland, UK
*tel: +44 1224 876544; fax: +44 1224 295511. e-mail: heathmr{at}marlab.ac.uk.
North Sea environmental and biological data were analysed to examine 30-year changes in production and consumption in the fish foodweb. The analysis revealed that the demand for secondary production placed on the ecosystem by fish declined from approximately 20 g C m–2 y–1 in the 1970s to 16 g C m–2 y–1 in the 1990s. Over the same period, the proportion of demand provided by zooplankton production increased from around 70% to 75%. The overall decrease was mainly due to a reduction in piscivorous demersal fish. Average secondary production by omnivorous zooplankton was estimated to be 35 g C m–2 y–1, and annual fluctuations were positively correlated with the gross production of planktivorous fish. The results suggest a "bottom-up" control of the pelagic foodweb. Individual planktivore species have been impacted by fishing, but the populations of other functionally similar species have expanded to fill the vacant niches, thus maintaining the planktivore role in the system. In contrast, the results indicate that benthos production was more "top-down" controlled. Overall, demersal fish species have been depleted by fishing, with no obvious species expansions to fill the vacant niche, releasing the benthos from predation pressure, and leading to an increase in benthic production and fisheries for invertebrates.
Keywords: benthos, demersal fish, fish diet, fisheries, food consumption, pelagic fish, plankton, production, stock assessment
Received 13 September 2004; accepted 28 January 2005.
CiteULike 
Connotea 
Del.icio.us What's this?
This article has been cited by other articles:
|
|
 |
|
  J. S. Collie, D. J. Gifford, and J. H. Steele End-to-end foodweb control of fish production on Georges Bank ICES J. Mar. Sci., June 25, 2009; (2009) fsp180v1. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. D. Rijnsdorp, M. A. Peck, G. H. Engelhard, C. Mollmann, and J. K. Pinnegar Resolving the effect of climate change on fish populations ICES J. Mar. Sci., April 2, 2009; (2009) fsp056v1. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. R. Heath The consumption of zooplankton by early life stages of fish in the North Sea ICES J. Mar. Sci., December 1, 2007; 64(9): 1650 - 1663. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
G. C. A. Duineveld, M. J. N. Bergman, and M. S. S. Lavaleye Effects of an area closed to fisheries on the composition of the benthic fauna in the southern North Sea ICES J. Mar. Sci., July 1, 2007; 64(5): 899 - 908. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. P.R. Greenstreet and S. I. Rogers Indicators of the health of the North Sea fish community: identifying reference levels for an ecosystem approach to management ICES J. Mar. Sci., January 1, 2006; 63(4): 573 - 593. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. G. Pitois and C. J. Fox Long-term changes in zooplankton biomass concentration and mean size over the Northwest European shelf inferred from Continuous Plankton Recorder data ICES J. Mar. Sci., January 1, 2006; 63(5): 785 - 798. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J.G. Hiddink, T. Hutton, S. Jennings, and M.J. Kaiser Predicting the effects of area closures and fishing effort restrictions on the production, biomass, and species richness of benthic invertebrate communities ICES J. Mar. Sci., January 1, 2006; 63(5): 822 - 830. [Abstract] [Full Text] [PDF]
|
|