Adaptive responses of tropical tuna purse-seiners under temporal regulations

Abstract

The failure to achieve fisheries management objectives has been broadly discussed in international meetings. Measuring the effects of fishery regulations is difficult due to the lack of detailed information. The yellowfin tuna fishery in the eastern Pacific Ocean offers an opportunity to evaluate the fishers' responses to temporal regulations. We used data from observers on-board Mexican purse-seine fleet, which is the main fleet fishing on dolphin-associated tuna schools. In 2002, the InterAmerican Tropical Tuna Commission implemented a closed season to reduce fishing effort for this fishery. For the period 1992-2008, we analysed three fishery indicators using generalized estimating equations to evaluate the fishers' response to the closure. We found that purseseiners decreased their time spent in port, increased their fishing sets, and maintained their proportion of successful fishing sets. Our results highlight the relevance of accounting for the fisher behaviour to understand fisheries dynamics when establishing management regulations.

Improving sustainable practices in tuna purse seine fish aggregating device (FAD) fisheries worldwide through continued collaboration with fishers

“…Furthermore, experienced fishers have valuable empirical knowledge on historical species distribution and abundances, and fishing technology evolution, which can help better characterize long and short-term population changes and effort creep, respectively. This non-official source of information is not only very useful in poorly monitored small scale artisanal fisheries (Johannes, 1998;Saldana-Ruiz et al, 2017;Alfaro-Shigueto et al, 2018;Berkstrom et al, 2019;Hunnam et al, 2021), but also in datarich industrial fisheries with rapid technological shifts and complex fleet tactics (Moreno et al, 2007a;Moreno et al, 2007b;Carruthers and Neis, 2011;Lopez et al, 2014;Macusi et al, 2017;Torres-Irineo et al, 2017). Furthermore, fishers' deep practical understanding of how fishing gear works and interacts with different species, gained through years of conducting fishing operations under varying conditions, is extremely valuable to improve selective fishing gear and practices (Hall, 2007;Jenkins, 2010;Poisson et al, 2014;Da Veiga Malta et al, 2019).…”

Descriptive and Spatiotemporal Analysis of the Tuna Purse Seine Fishery in the Colombian Pacific Ocean

“…The dynamics of the purse seine tuna fleet in the EPO have been detailed by Sun et al (2016), working on social and environmental factors for the spatiotemporal decision process of the purse seine fishery effort. As part of understanding the fisher behavior and the fisheries dynamics when establishing management regulations, Torres-Irineo et al (2017) found that the Mexican purse seine fishery associated with dolphins decreased their time at ports, increased their fishing sets, and maintained the proportion of successful fishing sets in response to closed seasons. Zhang et al (2021) analyzed the fishing behavior of tuna purse seine vessels spatially based on Automatic Identification System (AIS) data to identify the operating status of tuna purse seiners.…”