Using Tag‐Return Models to Estimate the Number of Times Fish Are Captured in Fisheries with High Catch‐and‐Release Rates

Abstract

Exploitation rates are often estimated using tag‐return studies. However, in fisheries with a catch‐and‐release component, exploitation rate or fishing mortality may not be the most important metric of interest. Instead, angler catch rates (e.g., fish caught per hour), total catch (including fish that are harvested or released), or the average number of times an individual fish is caught may be a better measure of fishery performance. However, if anglers remove tags from fish before release, then catch estimates will be negatively biased because tag removal will not be accounted for. In this study, maximum likelihood estimation methods were used to estimate catch in fisheries with high rates of catch and release. Right‐censored models were used to accommodate tags that may or may not be removed by anglers. Model‐derived maximum likelihood estimates of mean catch were relatively unbiased under two simulated fishery scenarios. There was a nonlinear, positive relationship between the percentage of tags that were removed from fish before release and the standard error of estimated mean catch. Although the models performed well at estimating catch in the simulations, more study is needed to evaluate how possible violation of model assumptions can affect catch estimates.Received October 19, 2015; accepted February 4, 2016 Published online May 26, 2016

Estimating Recycling of Fish in Catch‐and‐Release Fisheries

“…To the best of our knowledge, no one has published a method to quantify the increased catch realized through catch‐and‐release fishing. Recycling is often cited as the average number of times each fish is caught (Schill et al 1986; McCormick 2016), but these are estimates of seasonal catchability rather than recycling rate. Proof of recycling exists when catch exceeds abundance, but our methods allow for estimating recycling rate even when catch is well below abundance.…”

“…Some studies counted the number of times tagged fish were reported (Bahr et al 2018; Thorstad et al 2019). Others have combined creel data with population estimates to report the average number of times each fish in the population was caught (Schill et al 1986; McCormick 2016). However, neither of these metrics describes how much catch increased because of multiple recaptures.…”

Fisheries Volume 47 Number 12 December 2022

“…Some studies counted the number of times tagged fi sh were reported (Bahr et al 2018 ;Thorstad et al 2019 ). Others have combined creel data with population estimates to report the average number of times each fi sh in the population was caught (Schill et al 1986 ;McCormick 2016 ). However, neither of these metrics describes how much catch increased because of multiple recaptures.…”

Hook Wound Longevity and Use as an Indicator of Largemouth Bass Catch‐and‐Release Angling Pressure

“…) and allow fisheries managers to monitor the potential impacts of catch‐and‐release angling on fish populations (Pollock and Pine ; Kerns et al. ; McCormick ). Despite the utility of traditional tagging methods, several drawbacks of these techniques exist.…”

“…Fish tagging and marking techniques are essential tools for understanding population dynamics (Tranquilli and Childers 1982;Pine et al 2012) and allow fisheries managers to monitor the potential impacts of catch-and-release angling on fish populations (Pollock and Pine 2007;Kerns et al 2015;McCormick 2016). Despite the utility of traditional tagging methods, several drawbacks of these techniques exist.…”