Breakthrough for Indonesian scientists studying migration paths of pygmy blue whales

SINGAPORE – As the rare pygmy blue whale began to surface in the waters off Kupang in Indonesia, the researchers knew they had mere seconds to deploy their satellite tag before the marine mammal dove back underwater.

When the drone finally deposited the barbed tag onto the whale’s back in October 2025, the boat full of researchers observing the deployment from around 300m away erupted into cheers.

It had been their ninth attempt at using a drone to deploy the tracking equipment onto a pygmy blue whale, and the first time they succeeded.

Mr Mochamad Iqbal Herwata, the focal species conservation senior manager at Konservasi Indonesia, told The Straits Times in February that the successful drone-based deployment of the low impact minimally percutaneous electronic transmitter (LIMPET) tag marked a breakthrough for Indonesian researchers hoping to learn more about how pygmy blue whales move from Indonesia to Australia. The LIMPET tag is a type of satellite tag that can stay on marine mammals for several months.

Previously, drones were used to attach suction tags on these whales. Such tags typically stayed on the creatures for a few hours before dropping off.

LIMPET tags are usually attached to whales via a conventional airgun-based tagging method, which requires boats to be in close proximity to the whales. Such a tagging method can also cause tissue damage and stress in whales.

“It’s very risky; you need to have a good captain to mobilise the boat and make sure not to hit the whales,” said Mr Herwata, who was involved in the October expedition. “You also need a good shooter. If you miss the shot, you’ll lose US$5,000 (S$6,330),” he added, referring to the cost of the tag.

With the drones, scientists can now deploy the tags safely from a distance while minimising disturbance to the whale, and recover the tags easily if they miss their target, he said. “We believe that this can be a solution to make our research more ethical and less invasive.”

The October expedition was led by national foundation Konservasi Indonesia, and involved Timor-Leste researchers who joined as trainees. It was carried out in partnership with the Centre for Whale Research (Western Australia), Indonesia-based conservation organisation Thrive Conservation, and other local institutions. 

Following the deployment, the tagged whale travelled approximately 2,000km before the tag stopped transmitting information after 10 days, Mr Herwata said.

“For the first time, we are beginning to see the full picture of how pygmy blue whales move across national borders, from Indonesia through Timor-Leste and beyond,” he said. 

Mr Herwata said landing the tag marked a major step forward for whale research in Indonesia.

He added: “Drone-based LIMPET tagging allows us to gather critical migration data while minimising disturbance to the animal, and these insights are already helping us understand how pygmy blue whales move through the Lesser Sunda Seascape and how we can better protect them.”

The Lesser Sunda Seascape is one of the world’s most important whale migration corridors, and surrounds the Lesser Sunda Islands of Indonesia and Timor-Leste. 

The plan is to use drones to attach LIMPET tags to more whales to piece together a better picture of pygmy blue whale migration patterns, he added. 

In the latter half of 2026, Konservasi Indonesia and Conservation International Timor-Leste researchers will be conducting additional tagging in the region. 

They aim to expand movement data across the Ombai Strait, a high-traffic marine corridor where improved monitoring can help reduce risks such as whale-ship collisions. The findings will also contribute to

community-based ecotourism development

in Timor-Leste, Alor, and Wetar.

Experts say that understanding the movement patterns of pygmy blue whales could pave the way for the greater protection of these marine giants, such as by knowing where to site marine protected areas (MPAs).

After the expedition, Indonesia in December 2025 created the West Wetar MPA along the whale migration pathway, Konservasi Indonesia noted.  

Such data could also offer economic opportunities for communities in the region. They could, for example, potentially earn an income from whale ecotourism.

Pygmy blue whales can grow to around 24m, slightly smaller than the length of a basketball court. A subspecies of the blue whale, they inhabit the waters of the Indian Ocean. These migratory creatures are known to travel past Indonesia and Timor-Leste during their journey between the Banda Sea and Australian waters. 

While research efforts in Western Australia have helped improve understanding of the whales’ journey from Australia to Indonesia, the south-bound journey of these creatures currently remains one of the least documented migration patterns in the region, said Mr Herwata.

Knowing where whales stop to feed can inform the development of other MPAs, he added.

“When they find a critical area to rest, they will use it for several hours or maybe months. They have to make sure that they have enough energy to continue the journey.” 

The establishment of MPAs can also benefit local coastal communities by protecting nursery habitats, which in turn enables the rebuilding of fish stocks.

The presence of whales often signals highly productive waters, which are areas known to have dense prey aggregations that also support commercially important fish species, said Mr Herwata. 

By mapping whale movements and identifying seasonal feeding hot spots, scientists can generate indicators of when and where ocean productivity peaks, he added.

This can help communities and fisheries better plan fishing efforts, avoid sensitive periods or critical habitats, and reduce conflicts at sea. 

Importantly, MPAs can also unlock sustainable financing and long-term management support, creating local jobs in monitoring, patrol and conservation-based initiatives, said Mr Herwata.

Ms Patricia Chu, managing director of Mana Impact, a Singapore-based impact investment company with a focus on the oceans, said such research can also provide insights on the type of sustainable businesses and conservation enterprises that can be developed in the region.

Ms Chu, who was not involved in the latest expedition, added that communities who depend on ecotourism for their livelihood can also benefit from such studies, as it helps them better understand marine animal sightings. 

“Ecotourism can be a win-win solution in terms of providing both livelihood opportunities as well as positive environmental outcomes, as long as short-term economic wins are not prioritised over long-term sustainable ecological and economic benefits,” she said.