Fishing‐Related Stressors Inhibit Refuge‐Seeking Behavior in Released Subadult Great Barracuda

Abstract

Fisheries interactions that result in the capture and release of fish can cause behavioral impairments that increase the risk of postrelease predation. Increased predation risk has been attributed to reduced swimming capabilities; however, the role of refuge (structural shelter) use is still poorly understood. We examined the effect of fishing-related stressors on the ability of subadult Great Barracuda Sphyraena barracuda to attain refuge in an experimental wetland in Eleuthera, The Bahamas. Twenty-two Great Barracuda were either treated as controls with minimum stress, chased to exhaustion, or chased to exhaustion and air exposed for 90 s. Reflex action mortality predictors (RAMP) including ability to maintain equilibrium and bursting response were assessed prior to release at a standardized location. The prop roots of red mangrove Rhizophora mangle provided refuge about 5 m from the release point. Great Barracuda were visually monitored for up to 30 min postrelease to quantify behavior (resting, swimming, directional changes) and the time when refuge was reached. The RAMP scores increased with the degree of stressor, and fish in both fishing-related stressor treatments took significantly longer to reach refuge than control fish, while air exposed fish took significantly longer than fish that were only chased. Prior to reaching refuge, fish exposed to fishing-related stressors spent less time swimming, and changed directions more frequently than control fish, indicating that impaired locomotory capabilities and disorientation inhibited refuge use. The inability to find refuge after an acute stressor such as capture and release fisheries may be an important factor contributing to postrelease mortality for relevant species.

The future of recreational fisheries: Advances in science, monitoring, management, and practice

“…Predation can also be a conservation issue for angled fish post-release. There is growing evidence that fish exposed to greater C&R stressors (e.g., longer air exposure periods) exhibit impaired swimming and cognitive abilities post-release (Brownscombe et al, 2013(Brownscombe et al, , 2014bCooke et al, 2014), which can lead to increased vulnerability to opportunistic predators (Raby et al, 2014). For example, bonefish can experience post-release predation rates ranging from 0 to 80% depending on predator densities and bonefish condition upon release (Brownscombe et al, 2013; Cooke and Philipp, 2004;Danylchuk et al, 2007;Lennox et al, 2017).…”

A comparison of laboratory-holding and tag-return methods for evaluating delayed mortality of Dungeness crab (Cancer magister) discarded in Oregon fisheries

“…Also used are 4) in situ net pens or cages (Diamond and Campbell, 2009;Brownscombe et al, 2015;Bower et al, 2016); and 5) in situ visual monitoring (Campbell et al, 2010;Hochhalter, 2012;Brownscombe et al, 2014;. In conjunction with methods to determine mortality, the reflex action tol Bay commercial fishery.…”

Factors Influencing Postrelease Predation for a Catch‐And‐Release Tropical Flats Fishery with a High Predator Burden

“…Normal behavior, vigor, and refuge seeking can become impaired when fish are physiologically stressed or energetically exhausted (Danylchuk et al 2007a;Cooke et al 2014;Brownscombe et al 2014). Exhaustion, stress, and cognitive impairment are common consequences experienced by fishes that are captured and released by fisheries.…”

“…Exhaustion of the white muscles also precludes further burst exercise in the short term, compromising an important pathway used in predator evasion (Domenici and Blake 1997). Physiological stress also causes cognitive impairment, which results in poor decision-making by fish confronted by predators, including reduced refuge use (Campbell et al 2010;Cooke et al 2014;Brownscombe et al 2014). During this period of impairment, individuals recovering from the physiological effects of recreational angling become prone to post-release predation (i.e., PRP; Raby et al 2014).…”