Once again, Kodiak is celebrating Whale Fest. To celebrate the occasion and watch some whales, we packed a group of boys into our cars and headed out to Narrow Cape last Saturday.
Friday had been a pleasant and sunny day, and I hoped Saturday would follow suit.
It did not.
Clouds obscured the view of the mountains once we came over the pass to Pasagshak and the raindrops turned to hail, then snow. But just above Surfer Beach, we were rewarded with the first views of spouting whales, to be followed by numerous more sightings from the beach and the cliffs at Narrow Cape.
Why is Kodiak Whale Fest in April? It has to do with the annual migration of gray whales.
Many hundreds of gray whales have spent the winter months off the coast of Baja California, giving birth to their calves, finding mates, and lounging in the warm water. However, there is little for the whales to eat in that winter paradise, and after months of fasting they must search for better dining. For generations, whale mothers have taught their young the long journey north, past Kodiak Island and on to the rich feeding grounds in the Bering Sea.
Not every calf survives its first long migration. There are many dangers on the way, including orca whales. If a calf is separated from its mother, it has little chance of survival and becomes an easy meal for other marine predators.
Orca whales, unlike gray whales, possess a mouth full of conical teeth to grab and tear prey. These teeth are typical in the dolphin family, of which the Orca is the largest member.
Gray whales don’t have a single tooth in their huge mouths; instead, they have rows of baleen. Imagine bristles the size of the brushes in a car wash lining the upper jaws of a mouth the size of a small car. Gray whale baleen is shorter than the baleen of humpback, fin, or blue whales, which is an adaptation to their preferred food and method of feeding.
When looking from the air, you sometimes see plumes of mud following the path of a feeding gray whale. In the Ocean Science Discovery Lab, we watch a video clip showing underwater footage of gray whales feeding off the coast of northern Russia.
These whales seek out soft, muddy ocean bottom rich with small crustaceans (the “bugs” of the ocean). Then, turning their heads sideways, the whales plow through the mud, scooping mouthfuls of the sediment. When they close their mouths, their tongues push the water and mud through the gaps in the baleen, while the little crustaceans get trapped in the bristles. One swallow, and it’s a free ride for everything in the mouth to the whales’ stomachs.
The Bering Sea provides an abundance of tasty, nutritious, mud-dwelling crustaceans. This has to do with the shape of its bottom. As a shelf sea, large parts of the Bering Sea are shallow and flat. At the shelf edge, there is a sudden and steep drop-off. The currents sweep deep water against the continental shelf, and this brings a lot of nutrients to the shallow surface.
Nutrients spur algal growth in the spring and plankton becomes plentiful. In fact, these plankton blooms can be so sudden and rich that not everything gets consumed at the surface and some plankton die off and sinks to the bottom.
This in turn feeds those amphipods and cumaceans, which are the crustaceans preferred by the gray whales.
Today, I had a group of fourth-grade students at the Ocean Science Discovery Lab and we talked about sea otters and other marine mammals.
I asked them which marine mammals they could think of. One girl said “a wholphin”. At first I thought I didn’t hear her right, but she explained that it was a mix between a whale and a dolphin.
I had never heard of it before, but went home and looked it up. Sure enough, I found out that wholphins have a bottlenose dolphin mother and a false killer whale father and there is currently one female in captivity at an aquarium in Hawaii.
I have seen a Liger before (a mix between a lion and a tiger) and a mule (a mix between a horse and a donkey), but I had never seen or heard of a wholphin. Live and learn; there is no end to the amazing things nature has in store.
Switgard Duesterloh, Ph.D., is an assistant professor of natural sciences at Kodiak College. She operates the Kodiak Ocean Science Discovery Lab and teaches ocean science to students throughout the Kodiak Island Borough School District.