What should I know about baleen whales?
Baleen whales are the largest animals on earth, yet they feed on some of the smallest animals in the ocean. There are 12 baleen whale species divided into 4 families:
What is unique about baleen whales?
Baleen whales are some of the largest animals on earth. Characteristic baleen plates and paired blowholes help distinguish baleen whales from toothed whales. All cetaceans have a long, strong diaphragm which allows them to rapidly exhale as they surface and quickly inhale before submerging. The phrase "Thar she blows!" was coined by whale hunters who spotted the column of vapor as the whales exhaled.
How were baleen whales named?
Baleen whales were named for the long plates of baleen which hang in a row (like the teeth of a comb) from their upper jaws. Baleen plates are strong and flexible; they are made of a protein similar to human fingernails. Baleen plates are broad at the base (gumline) and taper into a fringe which forms a curtain or mat inside the whale's mouth. Baleen whales strain huge volumes of ocean water through their baleen plates to capture food: tons of krill, other zooplankton, crustaceans, and small fish.
Why were baleen whales hunted?
Early humans hunted whales for food and oil. But in the 19th and early 20th centuries, before the invention of plastic, whales were hunted commercially for their baleen or "whalebone" as well as for their oil. The whalebone was used to make women's corsets, buggy whips, and umbrella ribs. Most baleen whale species remain severely depleted because of this commercial whaling.
Right whales were called the "right" whales to catch by early hunters because they are large, swim slowly, have long baleen plates, contain lots of oil, and float when killed. Right whales do not have dorsal fins or throat grooves. The taxonomy of this family is rather confusing, but currently there are three species of right whales. Note that the pygmy right is in a separate family although it shares similar characteristics to right whales
Click on one of the right whale species to view information about them!
- Northern right whale (Glacialis glacialis)
- Southern right whale (Glacialis australis)
- Bowhead whale (Balaena mysticetus)
What are gray whales like?
Gray whales have their own taxonomic family, genus, and species. They are the most coastal of the baleen whales and are often found within a few miles of shore. Each year gray whales migrate between their summer feeding grounds in the Bering, Chukchi, and Beaufort Seas to their winter breeding grounds off Baja California, Mexico. This is one of the longest migrations by a mammal species.
Gray whales are gray in color and their skin is encrusted with barnacles and a unique species of small crustaceans known as "whale lice." They have 2-3 short throat grooves and instead of a dorsal fin they have a low dorsal hump followed by 6-12 "knuckles" or bumps. Whalers used to call gray whales "devil fish" because of their aggressive response to being hunted.
Click on the gray whale species link to view information about them!
- Gray whales (Eschrichtius robustus)
What are rorqual whales like?
Rorqual whales are relatively streamlined in appearance and have pointed heads and small pointed fins. They can be distinguished from other whales by many (25-90) deep groves along their throats that expand when they feed. There are 8 species of rorqual whales. This image shows a rorqual whale's throat grooves.
Click on one of the rorqual whale species to view information about them!
- Antarctic minke (Balaenoptera bonaerensis)
- Blue whale (Balaenoptera musculus)
- Bryde's whale (Balaenoptera brydei)
- Eden's whale (Balaenoptera edeni)
- Fin whale (Balaenoptera physalus)
- Humpback whale (Megaptera novaeangliae)
- Northern minke (Balaenoptera acutorostrata)
- Sei whale (Balaenoptera borealis)
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