From November 21st-December 11th, 2023, an international team of experts collaborated with the Environment Authority of Oman to conduct one of the most ambitious surveys for Arabian Sea humpback whales (ASHW) to date. At the height of the survey, which was coordinated by Future Seas, based in Oman, three boats were working in parallel in the Gulf of Masirah, implementing photo-identification, genetic sampling, acoustic sampling, body condition measurements, deployment of long-term satellite tags, and innovative new technology using drones to deploy short-term suction cup tags. The surveys also provided valuable opportunities for training and exchange of experience and expertise among scientists from Oman, the US, Canada, the Netherlands, the UK, Kenya and Slovenia.
Over the course of 11 full days on the water, the team documented 14 sightings of 10 individual humpback whales. All 10 whales were identified as individuals that had been observed in previous years and registered in the Oman humpback whale photo-identification catalogue, which is curated by the Environment Society of Oman. Some individuals had sighting histories dating back 22 years to October 2001 when they were first photographed in the same general area. Sloughed skin and biopsy samples for genetic analysis were collected from two individuals, and at least four individuals were singing when they were approached, allowing the team to record hours of high-quality song that can be compared with song collected in other parts of the Arabian Sea and the southern Indian Ocean to provide further insight into population identity and possible affiliations.
The leading objective of the survey was to begin a second phase of satellite tagging to build on the valuable data collected from the tags that were deployed in Oman between 2014 and 2017. This proved unusually challenging, as almost all the encounters with whales involved unpredictable surfacing patterns that prevented the ideal approach and alignment required for an optimal deployment. However, on the last day of tagging surveys, the team managed to deploy a tag on Individual OM22-001, named ‘Shamtain’, a whale first identified in the Gulf of Masirah in November 2022. The tag is still transmitting well, and the whale’s movements from the past three weeks can be viewed in the screenshot below.
The survey team also included two scientists working with Ocean Alliance, a US-based NGO that has developed innovative technology to deploy short-term suction cup bio-logging tags (CATS & Dtags) from drones. Five successful Dtag and two successful CATS tag deployments will yield valuable data to provide insight into the behaviour and energetics of this endangered population in order to support future conservation efforts. Click here to view a video demonstrating this amazing new technology.
The survey also yielded a valuable sighting of over 20 Endangered Indian Ocean humpback dolphins, and four sightings of Bryde’s whales, including a mother with a calf, providing insight into these species’ distribution and ecology. However, one of the most rewarding results of the survey was the exchange of experience and expertise that took place between all of the members of the team. Training sessions were held on data archiving and management, marine wildlife photography, methods for individual identification of whales and dolphins, the use of drones to film and measure body condition of whales, and satellite tagging safety protocols.
From left to right: 1) Tilen Genov, of Morigenos in Slovenia, shares his expertise on photo-identification of dolphins with members of the team from the Oman Environment Authority. 2) Chris Zadra, of Ocean Alliance, demonstrates the modified ‘snot-bot’ technology to deploy suction cup tags from drones. 3) Team members from the Environment Society of Oman and the Oman Environment Authority enter data at the end of the day – both are graduates of ESO’s recent Cetacean Research and Conservation Training programme. 4) Every aspect of the survey required close collaboration and hard work, including loading and unloading equipment onto the boats!
Stay tuned over the coming weeks and months as the team members analyse and report on the data generated from this valuable survey. You can follow updates on these social media platforms:
Environment Authority Oman:
see also: https://twitter.com/omanepress/status/1738949518052176212?s=46&t=_2bPN-JqVqpwI9_Sqj5Lwg
Environment Society of Oman
Arabian Sea Whale Network