Editor’s note: In the tiny Southeast Asian country of Timor-Leste, Conservation International (CI) and the University of Adelaide recently carried out a short survey to expand scientific knowledge of the range and abundance of whales and dolphins in the waters around the island nation. The survey’s results, which CI marine mammal expert Olive Andrews shares below, will help inform the management of these species.

Flying into the Timorese capital of Dili, I looked expectantly down into the vast blue of the Ombai Strait. In just one more sleep we would be on a boat searching the area for the largest creatures on our planet — blue whales — and their close
relatives.

Whales and dolphins make up the taxonomic order of marine mammals called cetaceans, which play an important role in the health and balance of the oceans and are iconic species for marine conservation efforts. But despite being beloved by humans, there’s still so much we don’t know about them — and little published information on the occurrence of whales in Timor-Leste specifically.

We do know, from tagging studies conducted by the Australian Marine Mammal Centre, that pygmy blue whales — a subspecies — travel from feeding grounds in southwestern Australia to the Banda Sea north of Timor-Leste, passing closely along the
country’s northern coast en route. Other studies carried out by the Timor-Leste government and partners have suggested that at least 13 species can be found here, and we were excited to experience some of these firsthand.

Day 1

Our team of marine mammal photographers, acousticians, data recorders and drone operators were ferried over to our research vessel in a small skiff. Once aboard, we distributed ourselves at high points on the boat from which to spot fins and blows. Before
long, there was a holler from above: “I’ve got something! Eleven o’clock, fins on the surface.”

As we approached, we were perplexed to find a pod of Risso’s dolphins in a tight group with tail flukes extended out of the water, essentially standing
on their heads. Like us, they were overheating in the still, humid air and were thermoregulating by putting their tails up out of the water to catch any available breeze — similar to how I, when overheating in bed, might stick a foot out of
the covers to cool down.

Day 2

In the early morning haze, we saw two huge blows and encountered two pygmy blue whales following the reef edge of Timor’s northern coast. Their huge bodies rising out of the ocean revealed pock marks caused by predation from cookie-cutter sharks that reside in the depths.
During their migration, these whales swim thousands of kilometers living off of their own body fat. When we spotted them, at the beginning of their journey, they were already emaciated, with their vertebrae clearly visible. These hungry whales have
a limited energy budget during this vulnerable part of their migration, so it’s good news that, thanks to the Timorese government, all whales and dolphins are protected in Timor-Leste waters.

Less than half an hour later, wide, dark fins began to appear all around us — a pod of around 400 pilot whales spread as far as the eye could see. This size pod is equally a cetacean researcher’s biggest thrill and worst nightmare, because
it is impossible to document them all! Fins flashed and darted around us as we frantically snapped photos, jotted notes and tried to count the number of calves and adults. Such a spectacle is truly rare to behold anywhere in the world.

Days 3-5

Over the next few days, we encountered a Cuvier’s beaked whale and her calf — a rare treat, as very little is known about this elusive species,
which is often at the surface for only a few breaths before diving to a depth of over 3,000 meters (9,800 feet). We also saw “superpods” containing hundreds of melon headed whales, spinner and spotted dolphins.

Given all of these encounters, we took this opportunity to deploy drones to collect aerial footage. After some glitches, the team was able to launch one of the “fixed wing” drones from a moving platform — an impressive feat. But despite
the skill of its operator, the drone managed to clip the transom of the boat on return and plummeted into the ocean. Almost immediately, a team member went overboard after it; after its dramatic rescue, the parts were meticulously taken apart, washed
in fresh water and dried. Eventually the footage — beautiful shots of breaching spotted dolphins — emerged unscathed from its unplanned dip.

During the survey, we also dropped an underwater microphone called a hydrophone overboard to listen to and record the dialects of the cetaceans we met. While listening to pygmy killer whales,
we were surprised to hear an underwater blast of dynamite — a sobering reminder that these waters and animals are a shared resource with neighboring Indonesia, where some unsustainable practices such as dynamite fishing continue, in addition
to cultural whaling practices.

In the end, over our five-day survey we sighted a remarkable 10 species in 25 pods amounting to over 2,200 individuals, confirming that Timor-Leste is a global hotspot for cetaceans. The survey also revealed the likely occurrence of pygmy spinner dolphins,
a species never before identified in these waters. These high numbers of whales and dolphins could offer Timor-Leste a great resource to develop community-based nature tourism — one of the most viable sustainable development pathways for the
country which could provide needed jobs and income for coastal communities.

CI Timor-Leste Marine Program Manager Alselmo Amaral teaching local trainees best practices for approaching cetaceans. The country’s high numbers of whales and dolphins could offer Timor-Leste a great resource to develop community-based nature tourism.
(© Olive Andrews)

Back on land, we convened a national workshop to review the conservation status of cetaceans in the Indo-Pacific region and begin drafting guidelines for the sustainable development of a whale-watching industry. We also held a training workshop for local
marine tourism operators, fishermen and guides from Dili and Atauro Island, which covered whale- and dolphin-watching best practices, species identification and behavior, minimizing impacts from vessel interactions and developing an on-board education
program.

One thing’s for sure: our team cannot wait to return to this incredibly rich and diverse place and continue this important research.

Olive Andrews is the marine program manager for CI New Zealand and Pacific Islands.

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Cover image: Fraser’s dolphins spotted in Timor-Leste. (© Olive Andrews)


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