Kooyman G L
Science. 1966 Mar 25;151(3717):1553-4. doi: 10.1126/science.151.3717.1553.
The probable maximum diving capacities of the Weddell seal were ascertained from observation of 959 dives and measurement of the depths of 381 dives. The deepest dive was 600 meters; the longest submergence was 43 minutes 20 seconds.