Tagging Gray Whales
Reprinted from: Oregon State University Marine Mammal Program

During the March 2005 field season, our research team went to Scammon's Lagoon, Mexico [Laguna Ojo de Liebre], to tag gray whales for the first time in nine years.

"Tagging" for Research
This research took place with shared funding from the BBC, Exxon/Mobil, the Sakhalin Energy Investment Company, and LGL Limited Research Company. The BBC is making a documentary on gray whale migration and calf mortality, so they sent a film crew to record our efforts. The crew chartered a panga (a local fishing skiff used by whale watching companies) and accompanied the tag team as they spent 10-hour days on the water. With our volunteer pilot flying overhead, locating whales and directing the tag team and film crew onto them, the season was an unqualified success. A total of 17 tags were placed, 16 on mothers with calves and one on a single individual. We actually ended the field season early, having accomplished our objectives. (We'd hoped to tag more singles, but they were very scarce so late in the season.)

Do Tags Hurt the Whales?
We're often asked if the whales react to being tagged. It's a difficult question to answer, since whales often demonstrate avoidance behavior around boats whether or not they‚ve been tagged. But this season, one of the gray whales came back to the surface about 15 minutes after being tagged, swam right to the boat and passed just beneath it. It seems safe to say the animal was not traumatized.

What Do Researchers Hope to Learn?
We're now watching the tagged whales as they transmit their location data. The plan is that as soon as they cross the U.S. border, the team will return to San Diego to begin relocation efforts in partnership with the BBC film crew. The BBC folks, of course, want footage of the gray whales during their migration. We want to assess the tag status and any possible physiological responses to the tags, as well as establish a calf count at various places along the migration route. If a calf disappears between Point A and Point B, then we‚ll know roughly where it vanished. Since calves have a fairly high mortality rate during the migration, this information is of considerable interest.