Use of Random Response to Estimate Angler Noncompliance with Fishing Regulations

We assessed noncompliance with angling regulations on three Idaho waters using random response, a technique designed to quantify embarrassing or criminal behavior. We searched for associations between positive random response answers and angler regulation awareness across a number of demographic variables. Illegal use of bait and creeling of westslope cutthroat trout Oncorhynchus clarki lewisi within two catch-and-release zones ranged from –0.4 to 3.0%. Creeling of illegal-sized cutthroat trout was a more common violation (5 to 8%) in two zones managed with a minimum size regulation. Estimated noncompliance with barbless hook regulations for the same zones was high (29%), but nearly 75% of these violations were accidental. Noncompliance with harvest restrictions was greatest on Henrys Lake where 9.5% of anglers violated the two-trout creel limit each day. We observed statistically significant associations between the types of regulations and angler ability to correctly recite them on a given stream. Several demographic variables including age, residence, and gear type used were also associated with regulation awareness. We conclude that random response is a viable method for estimating rates of angler noncompliance with regulations. Additional analyses are needed to evaluate potential biological effects of noncompliance on the trout populations.