Bottlenose Dolphins in the Adriatic Sea Rely on Trawlers for Food, Study Finds

Bottlenose dolphins in the Adriatic Sea are increasingly relying on trawlers for food, according to a study published on July 3, 2026. Researchers observed dolphins following fishing trawlers in the waters off Veneto and Marche, Italy. The findings suggest that the dolphins are struggling to hunt independently due to overfishing and ecosystem degradation.

Dolphin Behavior Around Trawlers

In a comprehensive study, scientists monitored trawlers from 2018 to 2025, conducting 859 inspections over 148 days. Their analysis revealed that up to 76% of the inspected trawlers in the Marche area were followed by dolphins, while only 26% in Veneto experienced similar activity. This disparity raises questions about the availability of prey and the adaptability of dolphin hunting strategies.

Dr. Giovanni Bearzi, president of Dolphin Biology and Conservation and lead author of the study, noted, "Long-term, consistent and deliberate association with trawlers suggests a high degree of reliance on that fishery." This behavior indicates that the dolphins may be facing challenges in finding food independently, particularly on days when trawlers are not operational.

Impacts of Overfishing on Dolphin Populations

The Mediterranean and Adriatic seas have seen significant overexploitation of fish populations. As apex predators disappear, bottlenose dolphins are left to scavenge for food near fishing vessels. The study found that dolphins follow trawlers primarily to access discarded fish or even venture into the nets to catch prey.

• 76% of otter trawlers in Marche were followed by dolphins
• 26% of otter trawlers in Veneto were followed
• Only 1.5% of beam trawlers attracted dolphins

Silvia Bonizzoni, co-author of the article, estimated that the combined bottlenose dolphin populations of Veneto and Marche exceed 1,000 individuals. Notably, between 86% and 90% of these dolphins were photographed while foraging near trawlers.

Conservation Recommendations for Dolphin Welfare

Dr. Randall Reeves, senior author of the study, expressed concerns about the potential risks dolphins face while foraging near trawlers. Dolphins may suffer injuries from trawl gear and experience chronic exposure to the noise of trawlers, which can lead to hearing damage. Despite these risks, dolphins may find scavenging behind trawlers to be a more viable option than hunting in an overfished sea.

Researchers advocate for conservation actions to protect marine biodiversity in the Adriatic. Dr. Bearzi stated, "As trawlers have been causing profound damage to Adriatic ecosystems, their continued use is inadvisable, not only to protect dolphins but also to conserve marine biodiversity more generally." This suggests that a reduction or ban on trawling could allow dolphin populations to thrive once again.