Kategorie: News
A whale that never migrates and a possible fourth subspecies
Humpback whales are considered one of the most migratory whale species of all; they travel thousands of kilometers annually between feeding grounds in cold waters and breeding grounds in warm waters. However, there appears to be one exception: The population in the Arabian Sea off the coast of Oman completely breaks this pattern.
A new study published in the journal *Frontiers in Marine Science* now provides, for the first time, genetic evidence that this isolation is deeply rooted in the animals’ evolutionary history. The humpback whales in the Arabian Sea remain in the same tropical and subtropical waters year-round, feeding and breeding there as well.
Whales in a Genetic Comparison
A team led by Rita Amaral of the Wildlife Conservation Society (WCS), in collaboration with the Environment Society of Oman (ESO) and other partners, compared mitochondrial DNA from 2,285 humpback whales from all the world’s oceans. The result: The population off the coast of Oman differs significantly from the three previously recognized subspecies in the North Atlantic, North Pacific, and the Southern Hemisphere. Genetic exchange with other populations is minimal, and genetic diversity is the lowest of all regions studied worldwide.
According to the researchers’ estimates, the divergence from other humpback whale lineages occurred between 43,000 and 113,000 years ago. “Humpback whales in the Arabian Sea have long been a mystery to the scientific community,” Amaral explained. The authors believe it is possible that this population could be recognized as a fourth subspecies, under the proposed scientific name Megaptera novaeangliae indica. However, the final decision rests with the Taxonomy Commission of the Society for Marine Mammalogy, which will now review the findings.
The study is further supported by a historical discovery: Researchers analyzed DNA from a bone collected in 1883 in the Persian Gulf region - in what is now Iraq - and described at the Natural History Museum in Paris as a separate species, Megaptera indica. Both morphological and genetic analyses confirmed that this is a humpback whale closely related to the current population in the Arabian Sea. This provides further evidence of the continuity of this isolated lineage over more than 140 years.
A Small, Endangered Population
These findings are not only of taxonomic interest but also have direct implications for species conservation. The Arabian humpback whale population is small and has not grown for about two decades. The population is threatened by fishing nets, ship traffic, underwater noise, marine pollution, disease, and changing monsoon patterns, on which the local food chain depends. Co-author Suaad Al Harthi of the ESO points out that Oman’s whale research began 25 years ago and has made enormous technological strides since then. The new genetic data will now help develop targeted, regionally coordinated conservation measures for a whale population found nowhere else in the world.
Further information:
Frontiers in Marine Science (Amaral et al. 2026, Original Study)
The National
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