Rorquals: Balaenopteridae

Rorquals (ROAR-kwulz) are large baleen (buh-LEEN or BAY-leen) whales. Like all baleen whales, they are filter feeders. These whales do not have teeth. Instead, they have many overlapping plates called baleen plates that hang like a curtain from the upper jaw. These plates are made of a material called keratin (KARE-ah-tin). This horny, fingernail-like material frays out into thin hairs at the end of each strand to make a strainer. Rorquals also have a set of ridges and groves along the bottom of their mouth and throat. When they open their mouth to feed, the grooves expand and make the inside of their mouth very large so that they can suck up a lot of water. They then push the water out through the baleen plates and use their tongue to lick up food that remains.

Rorqual whales can be anywhere between 32 to 102 feet (10 to 31 meters) long and weigh as much as 200 tons (181 metric tons). Some rorquals have a dorsal fin on their backs, and others have particular bumps or ridges on their head and back that help to distinguish them from other rorquals. Females are usually larger than males.