Arabian whales found to be genetically distinct from other humpbacks

Genetic research has revealed that the Arabian Sea humpback whale is a distinct subspecies, separate from other humpback whale populations. A study led by the US Wildlife Conservation Society and the Environment Society of Oman analyzed mitochondrial DNA from 2,285 humpback whales and found compelling evidence that the Arabian Sea population had its own evolutionary lineage.

The researchers discovered high levels of genetic differences between the Arabian Sea whales and the three recognized humpback whale subspecies in the North Atlantic, North Pacific, and Southern Hemisphere. This indicates limited gene flow between them. The Arabian Sea whales also showed the lowest genetic diversity among the ocean regions examined.

These whales are believed to have evolved tens of thousands of years ago, with divergence times ranging from about 43,000 to 113,000 years ago. Dr Rita Amaral, the study's lead author, noted that the Arabian Sea humpback whales have followed their own evolutionary trajectory for thousands of years and support their recognition as a distinct subspecies.

The isolation of this population also makes them vulnerable, facing threats from entanglement in fishing gear, vessel strikes, underwater noise, pollution, and natural stressors like disease. Climate-driven changes to monsoons and ocean upwelling may also impact their food availability. Oman's Environment Authority and Environment Society of Oman are committed to addressing the pressures faced by these whales and using the findings to guide conservation efforts.