6 Updated Cetacean Red List Assessments Published in December 2019


Assessments or reassessments of 6 cetacean species, subspecies or populations were published on the IUCN Red List in December 2019. This is in addition to the 2 published in July 2019, 5 published in March 2019, 35 published in November 2018, 10 in July 2018, and 19 in November 2017. A total of 77 updated or new cetacean assessments have now been published in the last 2 years.


The updated assessments were of the Sperm Whale (Physeter macrocephalus) which remains Vulnerable, the Indo-pacific Bottlenose Dolphin (Tursiops aduncus) which moved from Data Deficient to Near Threatened, and the Atlantic White-sided Dolphin which remains Least Concern. There were three new listings: the Lahille’s Bottlenose Dolphin (Tursiops truncatus gephyreus) and Peruvian Dusky Dolphin (Lagenorhynchus obscurus posidonia) are both listed as Vulnerable, and the Gibraltar Strait subpopulation of Killer Whales (Orcinus orca) is now Critically Endangered (see Table 1 for details). Work on new assessments and the remaining required updates is close to completion, and we expect them to be published in 2020.


Table 1. Summary of updated assessments and new assessments published in the 2019-3 (December) edition of the Red List. (NT = Near Threatened, DD = Data Deficient, CR = Critically Endangered, EN = Endangered, LC = Least Concern).

# Species/Subspecies Common name Taxonomic level Category Status change
1 Physeter macrocephalus Sperm whale Species (global) VU No change
2 Tursiops aduncus Indo-pacific bottlenose dolphin Species (global) NT DD -> NT
3 Lagenorhyncus acutus Atlantic white-sided dolphin Species (global) LC No change
4 Tursiops truncatus gephyreus Lahille’s bottlenose dolphin Subspecies (global) VU New listing
5 Orcinus orca Killer whale Strait of Gibraltar (subpopulation) CR New listing
6 Lagenorhynchus obscurus posidonia Peruvian Dusky dolphin Subspecies (global) VU New listing


The Red List status and documentation for the 89 currently recognised cetacean species as well as 41 subspecies or subpopulations can be found on the IUCN Red List website (redlist.org). Of the 89 species, 30% are assigned to a threatened category (i.e., CR, EN, VU, NT) and 29% are considered DD although ongoing reassessments of Data Deficient species are likely to result in some of them being reclassified in the near future (see Table 2). It should also be emphasized that there is strong interest in completing additional assessments of subpopulations that are known or thought to be at higher risk than the species as a whole (e.g., Killer Whales, Belugas, Dusky Dolphins).


Table 2. Summary information on Red List status as of December 2019.

Category Species Subspecies/subpopulations Total
Critically Endangered 3 17 20
Endangered 10 11 21
Vulnerable 7 10 17
Near Threatened 7 0 7
Least Concern 36 0 36
Data Deficient 26 3 29
Total 89 41 130