The role of temperature and cannibalism in interannual recruitment variation of bass in British waters

Between‐year variation in bass Dicentrarchus labrax year‐class strength in southern British waters is investigated. Mean spring‐summer seawater temperature in the year of birth was significantly positively correlated with both the level of summer recruitment of the 0 + group to the estuarine nurseries and subsequent recruitment of III + fish to the adult population. Spectral analysis of the temperature‐compensated time series showed that a statistically significant proportion of the variation not attributable to temperature was periodic at 0–33 cycles year −1 . Therefore, a simple, three‐parameter model, combining a linear relationship between temperature and abundance and a second‐order autoregressive model can be used to describe and predict variation in relative adult YCS. Bass remain for their first 3 years within their estuarine nursery areas. As I + fish were observed in Southampton water to cannibalize the 0 + group, it is suggested that strong year‐classes suppress recruitment for the next 2 years even if the temperature is suitable to promote a strong year‐class. Cyclic variation in recruitment caused by intraspecific interactions, particularly cannibalism, may be a feature of other marine fish that use estuaries as nursery areas.