Largemouth bass use prior experience, but not information from experienced conspecifics, to avoid capture by anglers

Abstract

Angler satisfaction is based on the presence of catchable fish, and therefore, understanding the mechanisms driving catchability is important for fisheries biologists and managers. Lure avoidance learning (including via social learning) may be a driver of catchability, but these mechanisms have not been explored in depth. To address this, largemouth bass, Micropterus salmoides (Lacépède), were stocked into four ponds, and two were angled using a green plastic worm. Naïve bass were then introduced into all ponds, and angling commenced using a sequence of three lures (green plastic worm, white plastic worm and in‐line spinnerbait). Naive bass stocked alongside experienced conspecifics were not less catchable, indicating socially learned lure avoidance did not take place. Catch rates declined across sessions until the switch to the spinnerbait, when rates temporarily spiked. This suggests that the similarity of a novel lure to previously experienced lures may determine if a fish avoids angling capture.

Hook Avoidance Induced by Private and Social Learning in Common Carp

“…Our data constitutes the first experimental evidence of social hook avoidance in Common Carp that lasts at least 7 d postcapture. Previous studies on Largemouth Bass (Wegener et al 2018;Louison et al 2019b) and Rainbow Trout (Lovén Wallerius et al 2019) failed to find evidence that social experience decreased hook avoidance in experimental settings. It is possible that the social threat TABLE 3.…”

“…Asterisks indicate significant differences (P < 0.05*, P < 0.01**, P < 0.001***). Louison et al (2019b) was not strong enough to foster social learning, thereby failing to promote a decline in catch rates for naïve observers. Specifically, Louison et al (2019b) tested the response of naïve observers when stocked in ponds with demonstrators that had previously experienced catch-and-release angling, i.e., the study was based on (indirect) observational conditioning and the observer fish were not directly exposed to a demonstrator being captured.…”

“…Catch and release has sublethal effects on fish (e.g., inducing hooking-related injuries and physiological stress responses; Pankhurst and Dedual 1994;Meka and McCormick 2005), which can lead to behavioral changes in released fish, such as decreased activity (Schreer et al 2005;Halttunen et al 2010;Klefoth et al 2011) and altered feeding (Stålhammar et al 2012). The experience of being captured and released can also induce hook avoidance learning, which has been documented in as diverse species as Common Carp (Beukema 1970a;Raat 1985;Klefoth et al 2013), Northern Pike (Beukema 1970b;Arlinghaus et al 2017aArlinghaus et al , 2017b, Largemouth Bass (Anderson and Heman 1969;Wegener et al 2018;Louison et al 2019b), and Rainbow Trout Oncorhynchus mykiss (Askey et al 2006;Lovén Wallerius et al 2019;Koeck et al 2020). Hook avoidance learning decreases overall angling vulnerability and can penalize future catch rates (Beukema 1970a(Beukema , 1970bvan Poorten and Post 2005;Klefoth et al 2013;Monk and Arlinghaus 2017).…”

“…Mechanistically, hooked and released fish learn from private hooking experiences (Beukema 1970a;Raat 1985;Louison et al 2019b;Lovén Wallerius et al 2019). In addition, it has been suggested that fish may also rely on socially transmitted cues that indicate threat, such as behavioral cues or the release of alarm pheromones (also called Schreckstoff) through injury of the epidermis (Pitcher 1993), to avoid future capture by angling (Beukema 1970a;Klefoth et al 2013;Lovén Wallerius et al 2019;Koeck et al 2020) or other fishing gear (Brown and Warburton 1999;Brown and Laland 2002).…”

“…Studies by Wegener et al (2018), Lovén Wallerius et al (2019, and Louison et al (2019b) suggest that social learning does not affect angling vulnerability of Largemouth Bass and Rainbow Trout, but Lovén Wallerius et al (2019) showed that in Rainbow Trout the social experience of catch-and-release angling induced a stress response compared with naïve individuals, suggesting that Rainbow Trout realized the threat. Moreover, in both Wegener et al (2018) and Louison et al (2019b) catch rates declined over time in experimental angling trials, with only a fraction of the stock being captured, either implying that there is a large pool of invulnerable fish or that some form of social learning took place to reduce reactivity to the gear. Indeed, Klefoth et al (2013) showed that an entire group of Common Carp was developing hook avoidance rapidly after just a few days of angling, despite only a fraction of the stock being hooked.…”