An Assessment of the Importance of Temperature as a Factor Controlling the Growth Rate of Brown Trout in Streams

Abstract

(1) The maximum growth rates of brown trout have been computed from temperatures in rivers and streams of contrasting character and location, using the growth model of Elliott (1975a) for trout on maximum ration. The high growth rates of trout in chalk streams may be largely explained by their ambient temperature regime, principally its relatively homothermous character. (2) Comparisons of observed and computed maximum growth rates, for the few locations where contemporaneous temperature and growth data are available, suggest that growth rates are generally between 60 and 90?4 of the computed maximum for that temperature regime and that this percentage is no higher in chalk streams.