A comprehensive study of a “rare and beautiful” whale spotted in UAE waters has found they may populate only the Arabian Gulf, emphasising the need for further research and greater conservation efforts.
A Bryde's whale carcass, 12 metres long and weighing 15 tonnes, was found in the Jebel Ali canal in June 2021 by emergency teams from Dubai World.
The giant animal was moved to a safe spot to allow UAE researchers to carry out analysis which, five years on, could pave the way for better understanding of the whale and help to safeguard its future.
Scientists say their results – which are tentative, as only a single example from the Gulf was available for genetic analysis – highlight the importance of more detailed studies of the local population of the Bryde’s whale.
They hope to carry out field analysis in the Gulf to identify more members of the species, providing a better idea of size and behaviour.
Results from analysing genetic material of Bryde’s whales from the UAE, South Africa, Japan and the North Pacific, against comparisons with other whales, have been published in Ecology and Evolution.
There are believed to be about 90,000 of the mammals worldwide, with the majority in the Northern Hemisphere.
The Bryde's whale is a relatively infrequent visitor to UAE shores but often grabs the headlines when sighted. In 2022, Sheikh Hamdan bin Mohammed, Crown Prince of Dubai, Deputy Prime Minister and Minister of Defence, shared a video of a Bryde's whale swimming around Dubai Marina, saying it was “truly a rare and beautiful creature to watch”.
Shedding light on species
One of the study’s authors, Dr Ada Natoli, assistant professor in Zayed University's College of Natural and Health Sciences, said the UAE specimen was genetically “really different” from large offshore types found near South Africa and Japan. It is also dissimilar to a smaller South African coastal type.
The researchers focused on the genetic material of tiny structures within cells called mitochondria.
“Independently of whether they are a different species or not, if they are a discrete population that does not migrate, that becomes immediately a concern in terms of conservation,” said Dr Natoli, a member of the International Union for Conservation of Nature’s Cetacean Specialist Group.
There is “very limited information” about the Bryde’s whale in the Arabian Gulf, she added, with scientists unsure of the population’s size or habits.
“We don’t know when they come to the Gulf, are they resident in the Gulf, what is their migratory range and where do they go,” she said.
The species, known scientifically as Balaenoptera edeni, has a subspecies called B. edeni brydei and another named B. edeni edeni, to which the UAE population appears to be more closely related.
Some specimens previously considered Bryde’s whales have been differentiated, with the Rice’s whale recognised as a distinct species in 2021 and another, smaller species, Omura’s whale, identified in 2003.
The new paper is titled Unravelling taxonomic complexity in elusive cetaceans: Mitogenome insights into evolutionary history and cryptic diversity of Bryde’s whales.
The International Union for Conservation of Nature classifies the species as of “least concern”, based on a global analysis that does not consider threats that particular and distinct populations may face.
Holding the key to conservation
Understanding how various populations differ will be important for conservation: if cohorts are highly distinct, they could eventually be classified as separate subspecies, or even species, and may need particular protection, as they could be under threat, even if they exist globally in large numbers.
The Bryde’s whale is a baleen that filters small fish other sea life using large plates in its gums, made of baleen, which, like human fingernails, is in turn made of keratin. Typically, they are 12 to 16 metres long and weigh 12 to 22 tonnes.
They are named after Johan Bryde, a Norwegian who set up whaling stations in South Africa in the early 20th century.
They are still hunted but only by Japan, which in 2024 killed 179, according to data published by the International Whaling Commission.
Previous analysis has indicated that pollution is not a threat to the Bryde's in the Gulf, which registered among the lowest levels of pollutants of all populations of the species.
However, ship strikes could be a threat, given the high level of traffic in the Gulf.
Dr Natoli and her colleagues at Zayed University are carrying out more genetic analysis on previous samples and they hope, in association with the Environment Agency Abu Dhabi, to undertake fieldwork, which could identify individuals and improve understanding of behaviour patterns. Planned fieldwork was put on hold because of the Iran war.
A range of evidence may show how distinct the Gulf population is, including physical form, such as skull shape and colouration, and their call.
UAE sightings
In 2023, an offshore survey involving the UAE Dolphin Project at Zayed University and partners including OceanX, the environment agency and technology company M42 recorded a sighting.
The following year, a Bryde's whale was seen off Fujairah and, two years earlier, a juvenile was spotted at Dubai. There have been other sightings off Abu Dhabi and Fujairah. “They do occur here. We just need to improve our data gathering, with more fieldwork,” Dr Natoli said.
The UAE specimen analysed in the latest study was 12 metres long and was found dead at Jebel Ali in 2021. Several organisations assisted in the work, including P&O, DP World, Dubai Municipality and the Environment and Protected Areas Authority of Sharjah.
Being “elusive” and difficult to sample, Bryde's whales are among the least-studied baleens, according to first author, Dr Dominique Paynee, of the University of Pretoria in South Africa.
Compared to the Gulf, more fieldwork has taken place off South Africa, where the whales are sampled using a crossbow that fires arrows with a hollow tip. These collect a small piece of blubber for genetic analysis.
To minimise stress to the animals, a maximum of three attempts are made to collect a sample, after which the whale is left alone.
Dr Paynee said carrying out fieldwork in the presence of the “massive creatures” was “amazing”.
“If you get a Bryde’s whale in a relaxed state and it’s just swimming, they’re really quite beautiful,” she said. “They’re very, I don’t know if you could say, shy creatures, they pop up and then they disappear.
“If they are feeding, it’s quite something to see. Their feeding behaviour, it’s really amazing, this super-powerful creature scooping up all these sardines and lunging through the water. The fieldwork is a really humbling experience.”
Prof Jean-Luc Jung, a researcher at the Ocean Institute, Sorbonne University Abu Dhabi, who was not connected to the study, described the work as “a major advance” in classification.
It suggests there could be a separate lineage of Bryde's whale in the Arabian Gulf, although, as the results are based on only one specimen, further research is needed.
“The nature of the Gulf and its limited contact with the Arabian Sea and the Indian Ocean make the existence of specific, endemic populations of marine fauna likely,” he said.
There is “much to learn” about the Gulf population, he added, including its numbers, degree of isolation, mobility and behavioural and feeding characteristics.
“Their interactions with human activities – which are particularly intense in the Gulf of Arabia – will need to be assessed as accurately as possible,” he said.
“Whales are not only iconic marine species but also important indicators of environmental quality. They serve as a barometer of marine biodiversity and, as such, deserve our close attention.”
