Publication Abstract

Is fish condition correlated with water conductivity?

G.H. Copp.

A relationship between body condition and water conductivity has been reported for some freshwater fish species whereby water conductivity was used as a surrogate (or correlate) of water productivity. To examine the potential wider applicability of this relationship, I tested for correlations between water conductivity and fish condition using body weight and environmental data collected during a study of mainly young-of-the-year (0+)fishes in the River Great Ouse, England, in 1990. Water conductivity and body condition factor were not correlated for any species of 0+ fish. However, condition factor increased significantly (P < 0.05) with increasing distance from source in two species, and either significantly or nearly significantly (P < 0.10) with increasing water velocity class in two other species. Condition factor decreased significantly or nearly significantly with increasing algal concentration class in four species. Much of the available evidence suggests that correlations between fish body condition and water conductivity probably reflect underlying broader geographical patterns in ecosystem function (e.g. ecological succession state/productivity) rather than an intrinsic relationship between fish condition and productivity.

Reference:

G.H. Copp. 2003. Is fish condition correlated with water conductivity? Journal of Fish Biology, 63: 263-266.