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Seasonal Changes in Movements, Abundance, Size Composition and Diversity of the Fish Fauna of the Severn Estuary

Published online by Cambridge University Press:  11 May 2009

P. N. Claridge
Affiliation:
N.E.R.C. Institute for Marine Environmental Research, Prospect Place, The Hoe, Plymouth PL1 3DH
I. C. Potter
Affiliation:
School of Environmental and Life Sciences, Murdoch University, Murdoch, Western Australia 6150
M. W. Hardisty
Affiliation:
School of Biological Sciences, University of Bath, Claverton Down, Bath BA2 7AY

Extract

Estuaries perform a crucial role in the life-cycle of many fish (Cronin & Mansueti, 1971; Day, Blaber & Wallace, 1981; Dando, 1984). They provide a migratory route for anadromous and catadromous species and an environment in which the limited number of true estuarine teleosts spend the whole of their life cycle. The upper reaches are colonized by certain freshwater species while the lower regions are penetrated by some marine fish during high tide. However, many marine teleosts enter and remain within estuaries for a period of time, often in very large numbers and particularly during the early part of life (see e.g. Gunter, 1938, 1961, 1967; Huddart & Arthur, 1971; van den Broek, 1980; Blaber & Blaber, 1980; Potter et al. 1983; Whitfield, 1983). The recognition that estuaries act as important nursery areas for certain teleosts by providing such features as a rich food source and protection from predation (see e.g. Pearcy & Richards, 1962] Jacquaz, Able & Leggett, 1977; Blaber & Blaber, 1980) has led to such species being referred to as estuarine-dependent (see e.g. McHugh, 1976; Beal, 1980; Fortier & Leggett, 1982).

Type
Research Article
Copyright
Copyright © Marine Biological Association of the United Kingdom 1986

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