Publication Abstract

The influence of parasitism on fish population success

MATT LONGSHAW^1*, PAUL A. FREAR², ANDREW D. NUNN³, IAN G. COWX³ & STEPHEN W. FEIST¹

The influence of parasitism on the first-year growth and recruitment success of two cyprinid fish species was investigated using a 14-year dataset in the Yorkshire Ouse catchment, North-east England. This study has demonstrated a significant role of parasitism in growth and recruitment success of lowland river roach (Rutilus rutilus (L.)) and European chub (Squalius (=Leuciscus) cephalus (L.)) populations. Statistically significant positive and negative correlations between levels of parasitism and year-class strength (YCS) and age-0 fish length were found. Infections in the muscle by the digenean Bucephalus polymorphus Baer, 1827 and the myxozoans Myxobolus pseudodispar Gorbunova, 1936and M. pfeifferi Thélohan, 1895were considered important, with strong statistical correlations between these parasites and YCS and fish length. Other parasites, such as Phyllodistomum sp. and Goussia sp., were implicated in host success to a lesser extent. Parasitism may be a major factor in fish population recruitment accounting for a very high proportion of the variance in establishing year-class strength, although this varied between locations.

Reference:

M. Longshaw*, P. A. Frear, A. D. Nunn, I.G. Cowx and S.W. Feist* (2010) The influence of parasitism on fish population success. Fisheries Management and Ecology 17(5): 426-434