Vanstreels Ralph Eric, Hurtado Renata, Ewbank Ana Carolina, Bertozzi Carolina Pacheco, Catão-Dias José Luiz
Laboratory of Wildlife Comparative Pathology (LAPCOM), School of Veterinary Medicine and Animal Science, University of São Paulo, São Paulo, 05508-270 SP, Brazil.
Dis Aquat Organ. 2016 Oct 27;121(3):241-248. doi: 10.3354/dao03052.
Fisheries bycatch, the incidental mortality that occurs as a result of entanglement in fishing gear, is an important conservation threat to penguins and other seabirds. Identification of entanglement and drowning in beach-cast carcasses of seabirds remains a challenge, as it is still unclear what lesions are to be expected in a bycaught seabird. We necropsied 2 Magellanic penguins Spheniscus magellanicus that were entangled and drowned in gillnets. Marked distension of the lungs with foamy red fluid and marked oedema of the dorsal visceral pleura were prominent lesions consistent with those described in cases of 'wet drowning' in humans. On the other hand, the air sacs contained very small quantities of liquid, suggesting that absence of water in the air sacs might not be a reliable sign to exclude drowning. Other relevant findings included cutaneous lacerations and bruising in one bird and cervical and pectoral rhabdomyolysis in both birds. While cutaneous or subcutaneous hematomas may be an indication of bycatch, especially if linear or cross-linear patterns consistent with fishing nets are present, these lesions might not always be discernible and their absence does not suffice to exclude the possibility of entanglement in fishing nets. Additionally, our findings suggest that the histological examination of skeletal muscles, particularly of the neck, may provide additional clues to corroborate the diagnosis of drowning in penguins.
渔业兼捕，即因被渔具缠住而导致的意外死亡，是对企鹅和其他海鸟的一个重要保护威胁。确定海鸟冲上海滩的尸体是否存在缠网和溺水情况仍然是一项挑战，因为目前仍不清楚兼捕海鸟会出现何种损伤。我们对2只麦哲伦企鹅（Spheniscus magellanicus）进行了尸检，它们被刺网缠住并溺水身亡。肺部明显扩张，充满泡沫状红色液体，背侧脏层胸膜明显水肿，这些显著病变与人类“湿性溺水”病例中所描述的一致。另一方面，气囊中含有极少量液体，这表明气囊中无水可能并非排除溺水的可靠迹象。其他相关发现包括，一只企鹅有皮肤撕裂和瘀伤，两只企鹅均有颈部和胸部横纹肌溶解。虽然皮肤或皮下血肿可能表明是兼捕所致，特别是如果存在与渔网一致的线性或交叉线性图案，但这些损伤可能并不总是能被察觉，而且没有这些损伤也不足以排除被渔网缠住的可能性。此外，我们的研究结果表明，对骨骼肌，尤其是颈部骨骼肌进行组织学检查，可能会为证实企鹅溺水诊断提供更多线索。
