The aim of the project was to document spatial and temporal distribution of Arabian Sea humpback whales in the region, investigate their singing behaviour and geographic variation, as well as assess potential threats to the population posed by anthropogenic noise. The project was conducted off the coast of Oman in Halaniyat Bay and the Gulf of Masirah from 2011 to 2013.
Currently listed as ‘endangered’ by the IUCN Red List, the Arabian Sea humpback whale has a population estimated to be less than 100. The study was undertaken as a matter of urgency and as a means to identify conservation solutions by acoustically assessing the presence and seasonality of whales, and monitoring the effects of ambient noise on whales.
Measuring sound is a critical factor for cetaceans as hearing is their primary sense used for foraging, migration and reproduction, and impairment of communication and hearing can have serious population consequences. The study involved three components - seasonal and geographic detections of humpback whale vocalisations off Oman; characterising ambient noise in the monitored regions; and comparing song structure variation across the western Indian Ocean - with groundbreaking results.
Suaad al Harthi, executive director of ESO, said, “I would like to thank our sponsors Shell Development Oman for funding and supporting this project. The research and the acoustic analysis has revealed valuable information about the Arabian Sea humpback whales, confirming the areas that are important to them, and the potential impact of noise pollution. Our conservation programme is ongoing and with the support of local and international partners we are able to develop and address conservation concerns.”
The detection of whale presence involves the highly effective method of Passive Acoustic Monitoring for assessing distribution across broad spatial and temporal scales. From continuously recording at three sites for two years, over a total of 1,369 acoustic recording days, it was discovered that the population utilises both the Gulf of Masirah and Halaniyat Bay for breeding.
Muna al Shukaili, general manager of External Relations and Social Investment Lead at Shell Development Oman, said, “We are proud to sponsor this initiative and help raise awareness on the impact human activities have on the Arabian Sea humpback whales. This is the reason we have collaborated with ESO.”