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Population Estimates. Estimates of current population size, known as abundance estimates, are derived from a combination of fieldwork and computer modelling. Vessel-based and aerial sighting surveys, acoustic monitoring, and analysis of individual animal markings are techniques used independently or in conjunction with each other to count whales.
- Status of whales
Status of whales. The IWC assesses cetacean status by...
- Status of whales
Countries with more than 25 species at risk of losing more than 25% of their habitat by 2050. Cumulative first records of alien species. Day of the year with peak cherry tree blossom in Kyoto, Japan. Drivers of recovery in European bird populations. Endemic amphibian species.
Status of whales. The IWC assesses cetacean status by population rather than by species. This is because the majority of species exist in several different areas and groups. Within a single species there may be one population that is feared to be close to extinction and one that is believed to be thriving.
Cetacea is an infraorder that comprises the 94 species of whales, dolphins, and porpoises. It is divided into toothed whales (Odontoceti) and baleen whales (Mysticeti), which diverged from each other in the Eocene some 50 million years ago (mya).
Whales range in size from the 2.6 metres (8.5 ft) and 135 kilograms (298 lb) dwarf sperm whale to the 29.9 metres (98 ft) and 190 tonnes (210 short tons) blue whale, which is the largest known animal that has ever lived. The sperm whale is the largest toothed predator on Earth.
Whales roam throughout all of the world's oceans, communicating with complex and mysterious sounds. Their sheer size amazes us: the blue whale can reach lengths of more than 100 feet and weigh up to 200 tons—as much as 33 elephants. Despite living in the water, whales breathe air.
There are around 90 species of whales, dolphins and porpoises, known collectively as "cetaceans". From the enormous blue whale to the tiny vaquita and Hector's dolphin, you will find information and amazing facts about many of these incredible creatures in our species guide.
