TitleBehavioural responses of juvenile Steller sea lions to abdominal surgery: Developing an assessment of post-operative pain
Publication TypeJournal Article
Year of Publication2009
AuthorsWalker, KA, Horning, M, Mellish, J-AE, Weary, DM
JournalApplied Animal Behaviour Science
Keywordssea lions

Marking and tracking of marine mammals is required to gain a better understanding of life history traits; however, some marking procedures used are likely painful. Recent technological advances include intra-abdominally implanted archival telemetry devices for the life-long monitoring of individual animals. No research to date has assessed any aspect of post-operative pain in marine mammals. This study specifically evaluated behavioural responses in nine juvenile Steller sea lions to the abdominal surgery required for insertion of telemetry devices. Behaviours predicted to reflect post-operative pain, including posture and body movements, were assessed during 3-day pre-, 3-day post-, and days 10–12 post-surgery. The proportion of time sea lions spent on land standing increased from 0.00 to 0.07 and then decreased to 0.04, for pre-, post-, and late postsurgery respectively. Similarly, the proportion of land time spent with the back arched increased from 0.01 to 0.57, and then decreased to 0.33. The time sea lions spent on land with pressure on their ventral side while sitting or lying down declined from 1.0 presurgery to 0.17 post-surgery, and increased to 0.20 late post-surgery. The time sea lions spent in locomotion on land and in the water decreased from 0.05 in pre-surgery to 0.01 post-surgery, and returned to 0.06 by late post-surgery. These results suggest that behaviours such as back arch, standing, time spent with pressure on the ventral side, and locomotion may be useful in the assessment of pain following abdominal surgery in sealions. The presence of these behaviours and their persistence for up to 12 days after surgery suggest that more work is required to further develop safe and effective analgesic methods for this procedure.