Joined in 2023 
82 
63 About this deal
Cooke JG (2018c). " Balaenoptera physalus". IUCN Red List of Threatened Species. 2018c. e.T2478A50349982. doi: 10.2305/IUCN.UK.2018-2.RLTS.T2478A50349982.en. |date= / |doi= mismatch
Owen, K.; Jenner, C. S.; Jenner, M.-N. M.; Andrews, R. D. (2016). "A week in the life of a pygmy blue whale: migratory dive depth overlaps with large vessel drafts". Animal Biotelemetry. 4 (17): 1–11. doi: 10.1186/s40317-016-0109-4. Balaenopterids are the rorquals. These animals, along with the cetotheriids, rely on their throat pleats to gulp large amounts of water while feeding. The throat pleats extend from the mouth to the navel and allow the mouth to expand to a large volume for more efficient capture of the small animals they feed on. Balaenopterids consist of two genera and eight species. [14] Blue whale calls recorded off Sri Lanka have a three‐unit phrase. The first unit is a 19.8 to 43.5Hz pulsive call, and is normally 17.9 ± 5.2 seconds long. The second unit is a 55.9 to 72.4Hz FM upsweep that is 13.8 ± 1.1 seconds long. The final unit is 28.5 ± 1.6 seconds long with a tone of 108 to 104.7Hz. [95] A blue whale call recorded off Madagascar, a two‐unit phrase, [96] consists of 5–7 pulses with a center frequency of 35.1 ± 0.7Hz lasting 4.4 ± 0.5 seconds proceeding a 35 ± 0Hz tone that is 10.9 ± 1.1 seconds long. [95] In the Southern Ocean, blue whales produce 18-second vocals which start with a 9-second-long, 27Hz tone, and then a 1-second downsweep to 19Hz, followed by a downsweep further to 18Hz. [97] [98] Other vocalizations include 1–4 second long, frequency-modulated calls with a frequency of 80 and 38Hz. [98] [99] List of Marine Mammal Species and Subspecies". The Society for Marine Mammalogy. 13 November 2016 . Retrieved 30 December 2019.Marrero, Meghan E.; Thornton, Stuart (1 November 2011). "Big Fish: A Brief History of Whaling". National Geographic. Archived from the original on 11 October 2015 . Retrieved 2 September 2015. Northeastern Ohio Universities Colleges of Medicine and Pharmacy (21 December 2007). "Whales Descended From Tiny Deer-like Ancestors". Science Daily . Retrieved 21 December 2007.
Gormley, Gerard (1990). Orcas of the Gulf: A Natural History. Lincoln, NE: toExcel. ISBN 978-0-595-01118-6. Between 1960 and 1992, the Navy carried out a program that included the study of marine mammals' abilities with sonar, with the objective of improving the detection of underwater objects. A large number of belugas were used from 1975 on, the first being dolphins. [141] [142] The program also included training them to carry equipment and material to divers working underwater by holding cameras in their mouths to locate lost objects, survey ships and submarines, and underwater monitoring. [142] A similar program was used by the Russian Navy during the Cold War, in which belugas were also trained for antimining operations in the Arctic. [143]The blue whale ( Balaenoptera musculus) is a marine mammal and a baleen whale. Reaching a maximum confirmed length of 29.9 meters (98ft) and weighing up to 199 tonnes (196 long tons; 219 short tons), it is the largest animal known ever to have existed. [a] The blue whale's long and slender body can be of various shades of greyish-blue dorsally and somewhat lighter underneath. Four subspecies are recognized: B. m. musculus in the North Atlantic and North Pacific, B. m. intermedia in the Southern Ocean, B. m. brevicauda (the pygmy blue whale) in the Indian Ocean and South Pacific Ocean, B. m. indica in the Northern Indian Ocean. There is also a population in the waters off Chile that may constitute a fifth subspecies. Blue whales off the Chilean coast may be a separate subspecies based on geographic separation, genetics, and unique song types. [26] [27] [28] Chilean blue whales may overlap in the Eastern Tropical Pacific with Antarctica blue whales and Eastern North Pacific blue whales. Chilean blue whales are genetically differentiated from Antarctica blue whales and are unlikely to be interbreeding. However, the genetic distinction is less with the Eastern North Pacific blue whale and there may be gene flow between hemispheres. [29] Description A blue whale with its bow wave, showing the blowhole Scammon, C. M. (1874). The Marine Mammals of the Northwestern Coast of North America. New York: Dover.
Great Deal 
New Comment