Evaluation of Michigan Creel Survey Catch Rate Estimator

摘要

Access-site creel surveys are conducted at numerous Great Lakes ports and on211u001einland water each year in Michigan to estimate angling effort and catch. 211u001eEstimated catch is the product of estimated angler hours and catch rate. Catch 211u001erate has been determined by averaging angler party catch per hour by species, 211u001eangling mode, and time period. This method for calculating catch rate is not 211u001eweighted by number of anglers in the party or by length of fishing trip which 211u001ecould lead to biases in estimates. Effects of bias on accuracy and precision of 211u001ecatch per hour estimates were measured using Monte Carlo sampling techniques on 211u001e132 data sets from Michigan access-site creel surveys. Each data set was 211u001econsidered a discrete population and population catch rate parameters were 211u001ecompared with sample catch rate estimates. Estimated mean catch rate by angler 211u001eparty was significantly greater than population catch rate parameters in 82 data 211u001esets and significantly less in 49 others. Due to trip length and angler party 211u001esize bias, the sample confidence limits were incorrectly represented in 123 of 211u001e132 data sets.