The IUCN considers sperm whales to be vulnerable to extinction, but after a 2008 assessment, experts are unsure if the sperm whale population is increasing, decreasing or stable. Scientists roughly estimate that there were about 1.1 million individuals in 1700 and the population dropped by about 67% to 360,000 individuals by the 1990s, due to whaling. Large-scale, commercial whaling ceased in about 1980 but it’s not clear whether sperm whale populations have since increased, or are still decreasing. Japan is currently the only country still hunting sperm whales, according to ZSL.
Sperm whales face other human-caused threats, such as entanglement in fishing gear, being struck by ships and pollution, according to the IUCN. The whales are included on the U.S. Endangered Species List and protected under the Marine Mammal Protection Act, according to NOAA.