Back to update.

Clues to Calves
"Telling the season's new calves from yearling whales is really tough," says biologist and calf expert Wayne Perryman. "Calves average about 7.1 meters (m) in length, while yearlings average about 8.5 m in length. That's not much difference! It takes experience and a really good look to get it right. We are lucky at Piedras Blancas because the cow/calf pairs swim directly towards us. The water is very calm. They often surface several times within 50-200 meters of us. This all helps us get a good look!"

Labeled photo showing a gray whale cow and calf on migration past Post 7Image: Michael H. Smith

Here's how calves differ from juveniles:

  1. Calves have very short heads relative to their body size. The distance from the rostrum to the blowhole is shorter in calves than in juveniles.
  2. Calves have a smaller blow than older whales.
  3. Calves and cows swim more tightly together than older whales do. A calf has a closer bond with its mother.
  4. Calves lack barnacles, or have far fewer barnacles than older whales.
  5. Calves have a clumsy way of surfacing. We generally watch cow/calf pairs (and adult/juvenile pairs) approach from about two miles away. Because we use 25X binoculars at the site, we can see and study them straight on for about 45 minutes as they approach. —Wayne Perryman