Finback Whale: Balaenoptera physalus
Genus/Species: Balaenoptera physalus
Common Name: Finback whale (widely accepted as Fin whale)
Federal Status: Endangered
FL Status: Federally-designatedEndangered
FNAI Ranks: Not ranked
IUCN Status: EN (Endangered)
The finback whale is the second largest whale in the world, with the blue whale being the largest. Finback whales in the Northern Hemisphere can reach a length of up to 75 feet (22.9 meters), while the Southern Hemisphere population can reach a length of up to 85 feet (25.9 meters). Females are usually five to ten percent larger than the males. This species’ smooth body is light black on the sides and dorsum (back), and white on the belly. Finback whales have “V” shaped marks on the back of their head and a curved dorsal fin located near the end of their back (National Oceanic & Atmospheric Administration, n.d., NMFS 2010.). Finback whales also have a pointed snout and paired blowholes.
The diet of the finback whale primarily consists of small fish, krill, and squids (National Oceanic & Atmospheric Administration, n.d.).
Finback whales are monogamous breeders (breeds with one mate). During courtship, males will voice low frequency sounds towards the females in hopes of luring her for mating. These sounds are necessary as finback whales do not have a specific area for mating, so they have to locate each other through the sounds. Mating and birthing happens in late fall to early winter every two to three years. The gestation period lasts up to 11.5 months, with the female giving birth to one calf. After birth, the mother will go into a dormant reproductive state for up to six months before reproducing again. Calves are precocial when born - they are able to swim immediately after being born with no help. Calves are weaned around eight months after birth which subsequently is when males will leave their mother to find their own pod (group of whales). Females will often stay in the same pod as their mother. Sexual maturity is reached around 6.5 years, with physical maturity reached around 25 years (National Oceanic & Atmospheric Administration, n.d.).
Habitat and Distribution
Finback whales inhabit offshore waters in all main oceans on Earth. Polar and temperate waters are preferred, as they are less likely to be found in tropical waters (National Oceanic & Atmospheric Administration, n.d.).
Historically, the finback whale’s population was threatened by capture and harvesting by humans. In 1987, the International Whaling Commission made the hunting of finback whales illegal (except for Greenland) (National Oceanic & Atmospheric Administration, n.d.). Residents in Greenland are allowed to hunt based on the “aboriginal subsistence whaling” clause, which states that aboriginal groups can still hunt because of their cultural hunting tradition (National Oceanic & Atmospheric Administration, n.d.). The main threat to the finback whale today is collisions with ships and fishing nets. Noise pollution can also cause a disturbance to the communication between whales. This threatens the finback whale, as they rely on communication when trying to find a mate. Other threats include habitat degradation (ocean pollution) and reductions in potential prey due to overfishing.
Conservation and Management
The finback whale is protected as an Endangered species by the Federal Endangered Species Act and as a Federally-designated Endangered species by Florida’s Endangered and Threatened Species Rule . It is also federally protected as a Depleted species by the Marine Mammal Protection Act.
-Federal Recovery Plan
Other Informative Links
American Cetacean Society
Animal Diversity Web
International Union for Conservation of Nature
National Oceanic & Atmospheric Administration
San Diego Museum of Natural History
Texas A&M University Corpus Christi
U.S. Fish and Wildlife Service Species Profile
Printable version of this page
National Marine Fisheries Service. 2010. Recovery plan for the fin whale (Balaenoptera physalus). National Marine Fisheries Service, Silver Spring, MD. 121 pp.
National Oceanic and Atmospheric Association. (n.d.). Finback Whale. Retrieved June 9, 2011, from NOAA National Marine Fisheries Service: http://www.nmfs.noaa.gov/pr/species/mammals/cetaceans/finwhale.htm
Image Credit NOAA