Discarded plastic bottles reduce dolphin bycatch by 88% in fishing nets

On July 2, 2026, researchers from Newcastle University revealed that discarded plastic bottles can significantly reduce dolphin bycatch in fishing nets. The studies showed that using plastic bottles as reflectors on gillnets led to an 88% reduction in dolphin bycatch without impacting fish catches. This innovative approach offers a low-cost solution to a pressing environmental issue.

Innovative Use of Plastic Bottles

The research focused on the use of plastic bottles and glass bottles as acoustic reflectors attached to fishing nets. These reflectors make the nets more detectable for echolocating marine mammals such as dolphins and porpoises. The project was initiated by Professor Per Berggren at Newcastle University, aiming to find a sustainable way to mitigate bycatch while addressing plastic waste.

In trials conducted in several countries, including Zanzibar, Peru, and Brazil, the team monitored over 1,600 fishing net deployments. The results were promising, showing that the addition of discarded plastic bottles helped dolphins avoid deadly gillnets.

Successful Trials and Findings

The first study revealed that while plastic bottles improved targeted fish catches in Zanzibar and Peru, neither glass nor plastic bottles reduced dolphin bycatch in surface-set fisheries. However, in Brazil's bottom-set gillnet fishery, the use of plastic bottles showed an 88% reduction in dolphin captures.

The second study, published in the journal Marine Mammal Science, further confirmed these findings. Between 2020 and 2025, researchers monitored 318 fishing trips and found that nets equipped with plastic bottles maintained fish catch levels while drastically reducing dolphin bycatch.

• Key Findings:
• 88% reduction in dolphin bycatch with plastic bottles.
• Fish catch remained unchanged.
• Successful trials in Brazil's bottom-set gillnets.

Future Research and Implications

Following the positive results in Brazil, further research is now being conducted in fisheries in Cambodia and Congo. The goal is to encourage the adoption of this simple yet effective method globally. Professor Berggren emphasized the importance of using plastic waste to benefit marine life, stating, "This is genuinely recycling that rescues dolphins." The researchers are keen to collaborate with governments and agencies worldwide to implement this low-cost solution to reduce dolphin bycatch.