Natural Perspectives: A lucky whale-watching trip indeed

A year ago, Vic and I went whale-watching with the Orange County chapter of the Society for Conservation Biology on one of Capt. Dave Anderson’s Dolphin Safari cruises out of Dana Point Harbor. It was the best whale-watching trip we had ever been on. When the conservation group organized another trip with Capt. Dave this year, we were the first to sign up.

There is nothing like an afternoon cruise on the ocean to beat the August heat. But on a Dolphin Safari cruise, we got a lot more than just a pleasant boat ride. We saw several fin whales, which were a new species for us, plus gigantic blue whales.

Summer in Southern California is the best time to see fin and blue whales. Fin whales are in the same family of whales, called rorquals, as blue, humpback, Bryde’s, sei and minke whales. This group of baleen whales is characterized by having a dorsal fin plus throat grooves that expand when the whales are feeding.

Blue whales are nothing short of spectacular. They are the largest animals to have ever lived on Earth, larger even than Tyrannosaurus rex. Fin whales are the second largest of the whales. Seeing both behemoths on one cruise was pretty darn exciting.

Fin whales are characterized by a long, sleek, streamlined body. Well, let’s just say that the body is streamlined for a whale. Adult males in the Northern Hemisphere grow to lengths of 75 feet and weigh between 50 and 70 tons. It’s kind of hard to think of anything that big as “sleek and streamlined” until you consider that blue whales in the Northern Hemisphere are 75 to 80 feet long, but weigh 100 tons. Both fin and blue whales in the Southern Hemisphere are even larger.

Fin and blue whales eat krill, which are small shrimp-like crustaceans that swim near the ocean surface. When the whales are feeding, their pleated throats swell to gigantic sizes as they take in water. Then they expel the water, using their baleen to filter out the krill. Blue whales feed exclusively on krill, but fin whales also eat fish. Fin whales are known to swim at high speed in ever-tightening circles, herding the fish into a tight school. Then they turn onto their right side to take in the school of fish.

Fin whales have an odd color pattern that differs from one side of their body to the other. The main body is light gray to brownish-black on the back and sides, with lighter-colored chevrons extending from below the blowhole down and back toward the fluke. The undersides of the body, flippers and fluke are white.

But it is the lower jaw of the fin whale that exhibits the odd color pattern. The left side of the jaw is gray or black, while the right side is creamy white. The baleen plates exhibit a similar asymmetry in color. And if you could see the tongue of a fin whale, you’d see that it shows a color pattern that is opposite that of the lower jaw, being dark on the right side and light on the left. Since these whales always turn to the right to feed, there is speculation on the part of scientists that the color differential confuses their prey.

Blue whales are a bluish-gray above and a lighter color below. In the cold waters of the Arctic and Antarctic, blue whales acquire a growth of diatoms on their bellies that gives their undersides a yellow-green color. For this reason, early whalers referred to them as sulfur bottoms.

Because this was a whale-watching trip that included conservation biologists, Vic and I did some research about whaling of blue and fin whales. The population of blue whales once numbered 350,000. They were too fast and too big for old-time whalers with their hand-held harpoons and open boats. But the invention of the exploding harpoon gun in 1868 put these speedy whales within reach of the hunters. As other species of whales rapidly declined, the whalers turned to blue whales in the early 1900s. In 1931, the peak year for taking blue whales, 29,000 were killed.

The hunts continued until 1966, when blue whales finally received protection from the International Whaling Commission. But 99% of them had already been killed. Recovery has been slow, with current estimates of only 3,000 to 4,000 left alive in the Northern Hemisphere. The situation with the southern population is slightly better, with between 5,000 and 10,000 left alive.

Fin whales, the second largest whales, were hunted more extensively when the population of blue whales declined. Between 1935 and 1965, about 30,000 were slaughtered each year. They too received protection in 1966. Because these whales spend so much time in deep waters, accurate counts haven’t been possible. However, it is thought that the population in the northern hemisphere is about 40,000, while the southern population has declined to about 15,000 to 20,000.

On this trip, Vic and I saw three fin whales and one or possibly two blue whales. Given the total number remaining in the world, we counted ourselves lucky. But for us, the real highlight was the number of common dolphins that we saw on the return to harbor. Two pods of several hundred dolphins swam and cavorted about our boat, riding the bow wave in close view.

The biggest threat to this acrobatic and friendly species is purse seine netting and being accidentally caught by the tuna fishing industry. Hundreds of thousands of common dolphins are lost in this manner.

You can learn more about the fascinating cetaceans that live off our coast by visiting the American Cetacean Society at https://www.acsonline.org. And don’t miss a chance to go out with Capt. Dave. Visit https://www.dolphinsafari.com or call (949) 488-2828 to get a reservation.

VIC LEIPZIG and LOU MURRAY are Huntington Beach residents and environmentalists. They can be reached at LMurrayPhD@gmail.com.