fish length-weight formula

Estimating the Weight of Freshwater Fish

An estimated weight can be obtained for many freshwater fish by measuring the length and girth of the fish at boat side.

When measuring fish, use the following procedures:

For length, lay the fish out flat and position the fish’s tail so that it extends as far as possible. Measure from the fish’s snout to the tip of the tail.

To measure girth, use a fabric ruler, measuring around the largest part of the body.

To estimate the weight of most freshwater fish, use this formula:

length x girth x girth / 800