Legal perspectives on unintended and unsanctioned humpback whale entanglement in the South Atlantic trawl fishery

Abstract

Whale interactions with fishing gear pose a major anthropogenic threat, yet entanglements in South Atlantic trawl fisheries remain underreported, with no published records. This lack of data extends to reports of whales found stranded with amputated tails, despite documented cases of survival even without a fluke. This study presents a novel case: a video recorded in May 2020 captured a shrimp trawler in Santa Catarina, Brazil, entangled with a humpback whale (Megaptera novaeangliae). Vocalizing and bleeding, the whale had recently lost its fluke and remained caught in the vessel's gear. Following the video's public outcry, authorities identified and apprehended the responsible vessel, conducting a thorough investigation. Although initial sanctions were issued, and evidence confirmed illegal fishing practices and neglect towards the whale, subsequent legal proceedings deemed the act unintentional and acquitted the involved parties. This report seeks to not only document this unprecedented case but also to analyze why such infractions against cetacean often receive minimal legal consequences. Examining this case within the context of broader policy and enforcement frameworks, we discuss potential explanations for the perceived low legal severity of such incidents and argue for the need for enhanced legal accountability to effectively protect marine mammals in the South Atlantic.