Balaenopteridae

Seri whale. Photo by www.marinebio.org

Defining Characteristics

• The body is streamlined, the snout pointed, the throat and chest grooved.
• The dorsal fin is hooked and set far back on the body.
• The tail is slightly notched at the mid-line, and scalloped along the posterior edge.
• The cervical vertebrae are not fused.
• The baleen plates are broad and short, the left and right rows being joined anteriorly.
• The animals are typically grey on the dorsal surface, with some white on the ventral surface; but Megaptera novaengliae humpback may be black above and below, with white flippers.
• Members of the family feed on krill and small fish, and occur in both hemispheres. They grow to 22 to 98 feet (7 to 30 m) depending on species.

Interesting Facts

• In this family of whales females are slightly larger than males.
• Southern hemisphere animals tend to be larger than those in the northern hemisphere.
• This family is known as ‘rorquals’, the Norwegian term for ‘furrow whales’.
• When they eat they hold enormous volumes of water in their throats before forcing the water through their baleen plates to filter out fish or krill.
• The blue whale was not hunted by Yankee whalers because of its speed and power, so the whalers went after slower whales like sperm, right and bowhead.
• The size of a Blue whale at birth is 20-28 ft (6 – 8.5 meters) long
• The Sei whale is the fastest whale reaching 35 mph (64km per hour)
• The Fin whale is known as “the Greyhound of the sea”

Habitat

• Distribution is worldwide:
• Blue, Fin, Humpback, and the Sei Whales are found in all major oceans;
• Common and Antarctic Southern Minke Whale species are found in all the oceans of their respective hemispheres;
• Bryde’s Whale and Omura’s Whale occur in the Atlantic, Pacific, and Indian oceans, being absent only from the cold waters of the Arctic and Antarctic.

Threats to survival

• Things that are harmful to these whales are pollution, hunting/whaling, and human disturbance.
• Ship strikes and entanglement in fishing gear also pose a major threat, killing several whales each year.

Cited Resources

• Carwardine, Mark. Whales Dolphins and Porpoises London: Dorling Kindersley Publishing, Inc, 1995. Print
• “Society for Marine Mammalogy – List of Marine Mammal Species and Subspecies” Society for Marine Mammalogy – Home. N.p, n.d. We. 8Mar. 2012
• http://animals.nationalgeographic.com/animals/blue-whale-interactive/
• http://www.britannica.com/EBchecked/topic/103892/cetacean/51591/Locomotion

Researched and written by Alfredo Parrilla, NBWM Apprentice, March 2012