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Online evidence suggests that there has been an increase in interest of using unmanned aerial vehicles or drones during land-based marine recreational fishing. In the absence of reliable monitoring programs, this study used unconventional publicly available online monitoring methodologies to estimate the growing interest, global extent, catch composition and governance of this practice. Results indicated a 357% spike in interest during 2016 primarily in New Zealand, South Africa and Australia. From an ecological perspective, many species targeted by drone fishers are vulnerable to overexploitation, while released fishes may experience heightened stress and mortality. From a social perspective, the ethics of drone fishing are being increasingly questioned by many recreational anglers and we forecast the potential for increased conflict with other beach users. In terms of governance, no resource use legislation specifically directed at recreational drone fishing was found. These findings suggest that drone fishing warrants prioritised research and management consideration. [ABSTRACT FROM AUTHOR]

Argyrosomus japonicus is arguably South Africa's most important estuarine recreational and small-scale fishery species. Although juvenile A. japonicus predominate in estuarine environments, where catch-and-release angling is common, limited C&R studies have taken place. The aim of this study was to use angler-behaviour to robustly examine the physiological stress response, reflex impairment and short-term (12–36-hour) survival of A. japonicus following C&R angling. Observations of estuarine recreational angling informed three air exposure treatments based on minimum (10 s), mean (75 s) and maximum (240 s) observed times, for use in a controlled angling experiment. Based on a prior laboratory study, blood sampling was delayed 30–40 min post-capture to allow for peak accumulations of lactate and glucose. Long air exposure (240 s) predicted significantly higher blood glucose concentrations (ANOVA, p = 0.03) than short (10 s) exposure. Similarly, both long (p = 0.01) and moderate (75 s; p = 0.01) air exposure significantly predicted elevated blood lactate concentrations, when compared with short exposure. In terms of physical impairment, long air exposure (240 s) had a significant negative influence on the reflex response (cumulative link model, p = 0.01) of A. japonicus. An observed short-term mortality of 7.7% was primarily attributed to hooking injury. To reduce significant physiological and physical stress, it is proposed that anglers should aim to reduce air exposure times to below the observed mean of 75 s, and ideally to 10 s. For relevant and meaningful future C&R studies, we propound the incorporation of angler behavioural assessments, and the investigation of physiological stress responses, prior to designing field studies. • Catch-and-release (C&R) impacts are underappreciated in South African fisheries. • Assessing angler behaviour can promote more meaningful C&R impact studies. • Physiological responses to C&R are reliably measured after suitable accumulation. • Air exposure is a major contributor to physical and physiological impairment. • Direct mortality is primarily associated with hooking injury. [ABSTRACT FROM AUTHOR]