Researchers track large marine predators across the globe
I spent the spring and summer of 2002 studying at Hopkins Marine Station, in Pacific Grove, Calif. — splashing around in tide pools, diving in kelp forests, and wading through mud in Elkhorn Slough. One of the highlights of my time there was helping Dr. Barbara Block and Dr. Dan Costa experiment with placing satellite tags on elephant seals. These seals can dive as deep as 1700 ft, spending up to 30 minutes underwater, so they were great test subjects to see how the tags would hold up.
After capturing a few seals on AÃ±o Nuevo Island and trucking them an hour down the coast to Hopkins, the scientists glued the tags on and released them, tracking their progress as they swam back home.
Block and Costa are lead scientists in the Tagging of Pacific Predators project. The project is helping them to understand where migrating sharks, leatherback turtles, bluefin tuna, seals, albatross, and other large marine animals spend their time.
Not only do the tags track the animals’ location, swim speed, and depth and duration of dives, but they also collect information about the temperature and salinity of the seawater, which is beamed back to the researchers via satellite. Fancy, eh?