CPUE as an index of relative abundance for nearshore reef fishes

Using density measurements derived by SCUBA diving, we have verified that research angling catch per unit of effort (CPUE) is a useful measurement of the relative abundance of nearshore reef species when the appropriate habitat is targeted. We found a strictly proportional relationship between lingcod and copper rockfish CPUE and density using a ranged major axis regression. This relationship did not hold for quillback rockfish since this study did not target their preferred depth range; nor for kelp greenling. Researchers must be aware of such limitations when using CPUE as a measure of relative abundance.