During their long foraging trips, northern elephant seals dive continuously, with little time spent at the surface. The potential volume of oceanographic data that a single elephant seal could collect on a single foraging trip is immense. We reasoned that if properly instrumented, calibrated, and archived, the elephant seal tags could provide oceanographic data for parts of the ocean where these are sparse or lacking. World Ocean Database. Note the apparent differences in foraging areas.
Outward tracks are solid lines, return tracks dashed.
All animals made complete return trips, but only those parts of the track with both temperature and satellite-based position data are shown. Provided by Wayne Perryman Southwest Fisheries Science Center Taking this step with data collected by animal tags has been hindered in the past by the accuracy of the sensors and geographic position where the measurements were taken. The newer generation tags have greatly improved measurement accuracy, and we determined that the quality of seal-collected temperature data are on par with that from XBTs. Thus, the seal data met the requisite criteria. We carefully evaluated data from foraging trips of six female and three male elephant seals tagged in central California between March 1998 and March 1999.