Abstract: The Marine Mammal Center hand reared a male Steller sea lion (Eumetopias jubatus) after it was found abandoned as a neonate in June 2006. Following release in April 2007, the animal repeatedly approached humans on the shore, necessitating long-term captive placement. To evaluate the extent of this preference for human contact, we conducted three behavioral assessments: (1) a stationary preference test, (2) a following test, and (3) a vocal playback test. This sea lion demonstrated an overall penchant for human interaction and a strong preference for the voice of one of his early caretakers. Filial imprinting, a developmental phenomenon extensively studied in birds but less so in mammals, is suggested as the cause of this aberrant social behavior. The long-term effects of imprinting in mammals, including impacts on reproductive success, remain poorly understood. This observation with a Steller sea lion is the first documented case of probable imprinting in this species.

Key Words: Steller sea lion, Eumetopias jubatus, imprinting, social recognition, development, pinniped

Document Type: Research article

DOI: 10.1578/AM.36.1.2010.79

Page Numbers: 79-83