Dear MARMAMers, On behalf of my co-authors, I am pleased to share our recent publication in Fisheries Research: Per Berggren, Joanna Alfaro-Shigueto, Jeffrey C. Mangel, Matt Sharpe, Narriman S. Jiddawi, Jeff Neasham, Gabriel Larre, Andrew J. Temple. 2026. Upcycled glass and plastic bottles offer potential low-cost mitigation to megafauna bycatch in gillnet fisheries. https://doi.org/10.1016/j.fishres.2026.107748 Highlights •Plastic and glass drink bottles tested as low-cost dolphin bycatch mitigation. •Plastic bottles used as acoustic reflectors and glass as mechanical pingers. •Plastic bottles offer promise to reduce dolphin bycatch in bottom set gillnets. •Plastic bottles may increase teleost and shark gillnet catch and reduce ray catch. Abstract Bycatch in gillnet fisheries represents the primary threat to cetaceans globally, yet mitigation has been hampered by a lack of effective, affordable solutions. Here we tested upcycled glass and plastic drink bottles as low-cost bycatch mitigation devices (mechanical pingers and acoustic reflectors, respectively) in gillnet fisheries across three regions. Observed trials were conducted in surface-set driftnet fisheries targeting teleosts and elasmobranchs off Zanzibar, East Africa, and Peru (2017–2021), and in bottom-set trammel net fisheries targeting teleosts off Brazil (2020–2022). Glass and plastic bottle treatments were tested against control sets across 1107 and 456 drift net sets in Zanzibar and Peru respectively, and 105 trammel net sets in Brazil. Catch differences between treatment and control sets were analysed using generalised linear hurdle and mixed models. Plastic bottles showed promise in Brazil, potentially reducing dolphin bycatch while increasing fish catch, though further trials are needed to confirm this. In Peru, glass bottles had no effect on dolphin, porpoise, or turtle bycatch but altered elasmobranch and teleost catches; plastic bottles similarly had no effect on dolphin bycatch but increased shark catch. In Zanzibar, no dolphin bycatch was recorded in any sets, though plastic bottles increased tuna catch. Overall, our results suggest plastic bottles may reduce dolphin bycatch in bottom-set fisheries, but neither device showed efficacy in surface-set fisheries. We encourage further trials of these and similar low-cost devices as accessible mitigation tools for small-scale fisheries. Paper is available here: https://doi.org/10.1016/j.fishres.2026.107748 Please get in touch if you have any questions or would like any further information. A follow up study is also available in this new paper by: Federico Sucunza, Antonio Barth, Daniel Danilewicz, Sarah Dolman, Lorenzo von Fersen, Gabriel G. Larre, Jeffrey C. Mangel, Paulo H. Ott, Joanna Alfaro-Shigueto, Andrew J. Temple, Nick Tregenza, Per Berggren. 2026. Evidence of Dolphin Bycatch Reduction With Upcycled Plastic Bottles Acoustic Reflectors Attached to Bottom-Set Gillnets. https://dx.doi.org/10.1111/mms.70189 Cheers, Per ___________________________________________________________ Per Berggren Emeritus Professor of Marine Megafauna Conservation, School of Natural & Environmental Sciences Newcastle University, NE1 7RU, UK Tel +44 191 2085676, Email: per.berggren@ncl.ac.uk<mailto:per.berggren@ncl.ac.uk> https://www.ncl.ac.uk/nes/our-research/marine/ https://perberggren.bsky.social<https://perberggren.bsky.social/> -------------------------------------------------------------------------------- [cid:d636ae44-df1b-442a-8919-23c3e980a53b] Latest papers: Upcycled glass and plastic bottles offer potential low-cost mitigation to megafauna bycatch in gillnet fisheries https://doi.org/10.1016/j.fishres.2026.107748 Evidence of Dolphin Bycatch Reduction With Upcycled Plastic Bottles Acoustic Reflectors Attached to Bottom-Set Gillnets https://dx.doi.org/10.1111/mms.70189 Offspring Size Resolves a Population Growth Paradox in Rays and Skates http://doi.org/10.1111/faf.70091 A roadmap for effective and sustainable marine protected areas: Beyond paper parks. https://doi.org/10.1016/j.jenvman.2026.12895<https://doi.org/10.1016/j.jenvman.2026.128956> Monitoring Risso's Dolphins in the Northeast Atlantic: A Deep Learning Approach to Classify Echolocation Click Detections http://dx.doi.org/10.1111/mms.70180 ______________________________________________________________
