7. blue whale (Balaenoptera musculus)
Whale-watching boat alongside a blue whale (Balaenoptera musculus), Sea of Cortez, Mexico. Adult blue whales can grow to lengths of more than 30 metres (98 feet). NaturePL/SuperStock
There are fewer than 25,000 blue whales, the largest animals on the planet. Comprising several subspecies, blue whales are found in all of the world’s oceans save the Arctic. The current population is thought to have been reduced by up to 90% by whaling in the 20th century. Commercial hunting of the species was ultimately banned in 1966. The National Marine Fisheries Service of the U.S. spelled out a recovery plan in 1998. It stipulated the maintenance of photo databases of individual specimens and the collection of genetic and migration data in order to better understand the species, which remains at risk from ship collisions and entanglement in fishing nets.
