Baleen

A baleen plate ranges from 1.6 to 11.5 feet long, depending on the species. Each plate can weigh an astonishingly 200 pounds.

Baleen Definition

Baleen is a filtering system consisting of fringed plates inside the mouths of baleen whales. When a whale opens its mouth, water rushes in. But the whale pushes the water back out, and all that’s left is food, such as krill. The bristles are arranged along the whale’s upper jaw and grow downward, lined perfectly as flexible slats. A baleen plate ranges from 1.6 to 11.5 feet long, depending on the species. Each plate can weigh an astonishingly 200 pounds. Right whales have the largest baleen, measuring 13 feet long and weighing up to 360 pounds.

Baleen Pronunciation

Baleen is pronounced [BUH] + [Leen]

Baleen: Evolution

The baleen filtering system evolved stepwise 30 million years ago. However, we only have fossils dating back 15 million years because baleen doesn’t typically fossilize. Scientists came to the estimate based on skull modifications. Before 30 million years ago, all whales had teeth and competed for food. Around this time, changes in ocean currents brought plankton blooms, a new food source for whales. After developing a taste for this new food, baleen whales split off and became different species.

New studies also suggest that whales didn’t become giants until about three million years ago when they could binge-feed by filtering. However, much debate surrounds the evolution and phylogenetic history of baleen whales. Today scientists are studying the chemical timestamps located within the keratin of the baleen. These studies can help us learn about a whale’s health, movements, reproduction, and how climate change is affecting these species.

Is Baleen a Bone? What is it made of?

Baleen is made of keratin, the same substance found in human hair and fingernails. The mostly mineralized keratin bristle is strong, yet flexible, perfect for catching krill, small fish, and copepods. Baleen is also referred to as “whalebone.” But this is a misnomer because baleen is not actually a bone.

What Do Humans Use Baleen For?

Baleen has been popular for human products for a long time. Its strong flexibility makes it perfect for many household and essential items. People used baleen to weave baskets, buggy whips, corsets, umbrellas, backscratchers, stiff petticoats, and bows. In 1972, the United States made it illegal under the Marine Mammal Protection Act to purchase, export, sell, or transport any marine mammal products, including baleen. Today we use plastic and fiberglass to make similar items.

Why is Baleen Valuable?

The term “whalebone” came about in the fashion industry during the 19th century. Baleen proved valuable in shaping stiff clothing because it could also be flexible. It was used to create corsets and collars and the famous hooped frame for skirts. Its usefulness as a construction material made it highly desired. Before it became illegal, people used to hunt and kill whales for their baleen and blubber, which was used for oil to make candles and cosmetics. Hunting whales were popular well before the 19th century though. Researchers believe people use to hunt small whales as early as 6,000 BC, using every part, whether for food or construction.

Do All Whales Have Baleen?

Only baleen whales have baleen. The other category of whales has teeth. The difference between the two is how they feed. Baleen whales are filter feeders, sieving their prey from the seawater. And toothed whales actively hunt animals like fish, squid, and other marine creatures. Baleen whales, or mysticetes, are comprised of three families and 16 species. 

The smallest baleen is the pygmy right whale, measuring 20 feet long and weighing 6,600 pounds. And the largest baleen whale is the blue whale, measuring 102 feet long and weighing up to a whopping 400,000 pounds. The blue whale is the largest living animal on earth, and it eats one of the smallest animals. Baleen whales are some of the most giant creatures on our planet thanks to their love of krill and the fascinating filtration system of baleen bristles.