Monday, January 8, 2018

Marine Species: Baleen Whales

There are over 80 species of cetaceans in total, including whales, dolphins and porpoises. We split whales into two distinct suborders: toothed and baleen whales. There are around 65 different species of toothed whales, and 15 baleen whales. Baleen whales are almost always larger than toothed whales, as well as being slimmer and more streamlined. Additionally, baleen whales have two blowholes, while toothed species have one.

Baleen whales usually travel in smaller groups or are solitary, except when mating or during some forms of migration. They also dive in shorter intervals coming up for breath every 10 minutes or so. Baleen whales also tend to dive shallower than toothed species. The deepest-diving baleen whale is the fin whale, with a record dive to 1,500 feet (470 m) deep.

Their defining feature, however, is that baleen whales are born with plates rather than teeth. These baleen plates are made of keratin, and they act like strainers when the whales swim with their mouths agape, using these bristles to filter plankton and krill from a huge mass of water. Here are five baleen whales that represent some of the extremes of the species — the largest, deepest diving, most researched, longest migrating and most unusually colored.

Blue whale

The largest creature to inhabitant the planet, the blue whale can reach lengths of up to 100 feet (30 m). An adult can weigh over 110 tons (100,000 kg). Despite its name, the blue whale is actually dappled gray, with many darker blotches on its skin. The blue whale has a small dorsal fin in relation to its body. The blue whale can live up to 100 years, and we see them most frequently near Sri Lanka, Baja California and the Azores Islands. Blue whales prefer deeper waters, migrating to the poles in the summer to feed, and to the tropics in the winter to breed.

Fin whale

The fin whale is the second-largest whale species, darker gray in coloration than the blue whale. They can grow to 90 feet (27 m) long and weigh around 100 tons (91,000 kg). You can identify the fin whale by the white coloring of its jaw on the right side. The fin whale has a prominent dorsal fin and a sleek, streamlined body, allowing it to swim at speeds up to 20 knots. The whales routinely dive to 660 feet (200 m).

Humpback whale

One of the most well-known whale species, the humpback is popular for its breaches, spy-hops and pectoral slaps. Its long pectoral fins and knobby head make it one of the most distinctive-looking whales. Adult humpbacks can reach lengths of 39 to 52 feet (12 to 16 m) and weigh nearly 44 tons (40,000 kg). Categorized as a whale of least concern on the IUCN Red List, some populations of humpbacks could return to pre-whaling numbers by 2050.

One of the most researched of all marine species, humpbacks live in all the global oceans. Researchers and whale watchers use the long pectoral fins and flukes to identify various individuals. Divers and snorkelers often encounter humpback whales in the waters off Tonga, the Dominican Republic, South Africa and Alaska. Humpback whales are known for their complex and fascinating songs. Only male whales sing in, although researchers do not know why or what the songs mean. The whales can sing for 20 minutes, with Pacific and Atlantic species each singing different songs. 

Gray Whale

Gray whale

Once known as the devil-fish due to its ferociousness when hunted, the gray whale is now famous for human interactions in the shallow breeding grounds of Baja California’s San Ignacio Lagoon. Visitors can reach into the green waters and stroke the rough skin of the most curious whales. Reaching a length of 60 feet (15 m) and a weight of 40 tons (36,000 kg), the gray whale is also the longest-migrating whale. The furthest one has been recorded as traveling is 22,000 miles (40,000 km).

Bowhead whale

The bowhead whale is one of the most unique of all marine mammals, due to its thick structure and black and white coloring. The bowhead whale lives in northern Polar waters, where humans hunted them to near extinction until the 1966 moratorium was passed. Numbers are slowly recovering, with estimated populations hovering around 40,000. Bowhead whales are solitary animals, although they sometimes swim in pods of up to six animals. With a maximum length of 60 feet (18 m), and a weight of 110 tons (100,000 kg), this whale is famous for its huge head. Inuit hunters have recorded the animal breaking through up to 24 inches (610 mm) of ice. The head itself can make up 10 feet (3 m) of the entire whale. This means it’s got the biggest baleen of all whales — blue whales included.

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