Disentanglement and Multi-Year Survival of a California Sea Lion with an Upper Airway Stoma Due to Entanglement

Disentanglement and multi-year survival of a free-ranging California sea lion (Zalophus californianus) with an upper airway stoma secondary to fishing net entanglement

Entanglement

Abstract

California sea lions (Zalophus californianus) are susceptible to entanglement in fishing gear and marine debris. Over time, entanglement material can become deeply embedded and disrupt underlying tissue layers, including skin, blubber, muscle, and regional structures. In the neck, chronic circumferential entanglement can result in airway laceration. We present a case study of an adult female California sea lion with an upper airway stoma secondary to chronic monofilament fishing net entanglement. The animal was disentangled in a remote field setting without access to surgical and rehabilitation facilities, and was released without additional treatment. Satellite telemetry data from the 5 months following disentanglement revealed movements comparable to those of other adult female California sea lions. Subsequent visual sightings (’resights’) documented a minimum 2-year survival following disentanglement.

Whitmer, E.R., Harris, J.D., Orr, A.J., Saunders, S.B. and Johnson, S.P., Disentanglement and multi‐year survival of a free‐ranging California sea lion (Zalophus californianus) with an upper airway stoma secondary to fishing net entanglement. Veterinary Record Case Reports, p.e713.

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