A cold-stunned, sub-adult, female loggerhead sea turtle (Caretta caretta) was found stranded in December 2012 on Cape Cod, Massachusetts. The turtle was treated routinely; however, she did not gain weight as expected during rehabilitation. Eleven weeks after stranding, staff noticed stertorous upper airway sounds. Oral examination revealed a unilateral laryngeal paralysis-like condition resulting in partial airway obstruction. Magnetic resonance imaging and electromyography showed abnormalities of the abductor arytenoideae muscle. Muscle and hepatic biopsies were collected for histologic and toxicologic assessment to seek an underlying cause of the disorder. The turtle did not recover from anesthesia, and necropsy revealed a large amount of hemorrhage from the liver biopsy site. Unilateral myofiber atrophy of the abductor arytenoideae muscle was the predominant histological finding.