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They’re All Heading South

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Whale Watching | Mammals

Thursday, December 10, 2009


We’re a bit into December now and at this time we’re waiting for the gray whales to start passing by as they head south for the winter. While we’re out looking for the first grays, besides looking at the seals, sea lions, a variety of dolphins and sea birds, we’re STILL seeing blue whales!

It seems that a lot of the blues have decided to hang around a little longer this year. More than likely the food is still strong here, so they don’t need to leave yet. Now unlike the gray whales, it’s not quite as clear as to where the blue whales go in the winter. The gray whales head to the lagoons in Mexico like they have been doing for years. The blue whale winter spot hasn’t quite been found yet. Scientists think that the blue whales might go to an area off of Costa Rica called the Costa Rican Dome.

What makes the Costa Rican Dome so special is that it’s an area where there is a lot of upwelling. That means that a lot of cold water that is really deep is brought up to the surface, bringing lots of nutrients with it. Having nutrient rich waters is very important because that supplies an area with a lot of food. This is why a lot of whales spend their summer months up north in the colder waters. They’re feeding. In the winter time, they head south to the warmer waters to give birth to their babies. Giving birth to babies in warm water is extremely important because the babies aren’t born with any blubber, which is a form of insulation like fat. The babies spend a couple of months drinking their mother’s milk to get nice and blubbered up. This also means, however, that because the water is warm, there won’t really be any food! So in the winter time, gray whales don’t feed at all on their migrations into the warm waters!

It’s thought that because the blue whales are so large, they HAVE to eat all year round. The Costa Rican Dome is a good spot for them because there’s the upwelling that allows for there to be food for the whales, and it’s also warm enough to have the babies.

By this time the blues are normally gone and the gray whales are just starting to pass by. Even though we see these whales at different times, they’re both heading south for the winter where they can mate and calve for the year. Lucky for us the blues are still here and we might even see the two overlap. If you’d like to join us in looking for whales as they head south, click here!

They’re All Heading South
Two gray whales show their flukes as they head on a deep dive during their migration.  | Kera Mathes
They’re All Heading South
A blue whale surfaces as it hangs out in Southern California during the summer.  | Kera Mathes
They’re All Heading South
A blue whale shows its fluke as it deep dives.  | Kera Mathes

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