Variation in the condition of northern pike, Esox lucius

The relationship between condition and latitude, temperature, and sex of northern pike was examined by regression analysis of 5210 published observations drawn from more than 38 populations. Most populations showed nearly isometric growth, but the overall exponent of the power function relationship between total body length and body weight was slightly less than 3. Females weighed c 9% more than males of equal length; body weight for fish of equal length increased c 5% for every 10° increase in north latitude and increased about 4% for every 10°C decrease in mean annual air temperature; and fish in European and Asian populations attained c 13% greater weight for a given length than their North American counterparts. -from Authors