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t has been years since conservationists first announced that they had found evidence of the existence of Irawaddy dolphins in waters in Kubu-Batu Ampar in Kubu Raya regency, West Kalimantan, but follow-up surveys have yet to reveal the precise size of their population in the area.

In 2012, for the first time ever, World Wildlife Fund (WWF) Indonesia and its local partner the Regional Office for Marine, Coastal & Resources Management Pontianak (BPSPL), confirmed the existence of Irrawaddy dolphins, along with the Humpback dolphin, in West Kalimantan waters.

The Irawaddy dolphins found in West Kalimantan are believed to be different from those in Mahakam river in the eastern part of the island, whose population is currently estimated at around 87 according to WWF Indonesia. Irawaddy dolphins in Mahakam river live in freshwater, while those in West Kalimantan live in mangrove forest waters.

Since 2012, local conservation group JARI Indonesia West Borneo has tried to identify the presence, species and habitat of Irawaddy dolphins in West Kalimantan.

However, despite years of continuous studies on the West Kalimantan population, conservationists cannot yet reveal the precise size of the population.

One of the biggest challenges facing the conservation effort is the difficulty identifying the peculiar animal, which is known to be very shy and sensitive, making it difficult to capture its full body. They are relatively different to other oceanic dolphins, which tend to show off their full bodies when they surface.

JARI West Borneo activist Sumiati said the dolphins often surfaced in two groups of five to seven individual animals. One adult Irawaddy dolphin is estimated to weigh around 100 kilograms.

“We haven’t found any data or claims of Irawaddy dolphins living in mangrove forest waters [as a comparison] so this survey is very challenging,” Sumiati said in Kijing beach, Sungai Nibung village, Kubu Raya regency, recently.

Sharing the sentiment, BPSPL Pontianak conservation section head Syarif Iwan Taruna Alkdrie acknowledged the big hurdle that the team was facing, saying that it took eight years to survey “only” dozens of kilometers of river in the Mahakam area to map out the Irawaddy dolphin population. Meanwhile in Kubu Raya regency, researchers have to cover at least six rivers in Kubu Raya-Batu Ampar waters, in which Irawaddy dolphins often appear.

Kubu Raya waters cover North Kayong regency, the outmost part of West Kalimantan, and extend to the South China Sea.

“Kubu waters are extremely vast. It’s difficult to confirm the population, particularly when we rely solely on field inspection,” he said, pointing out that they identified between 16 and 26 dolphins in each survey.

Syarif said that a DNA test confirmed that the Irawaddy dolphins in West Kalimantan waters were different from those in Mahakam river.

“Which makes them even more special to preserve,” he said, suggesting that the conservation effort is in line with ecotourism programs.

He added that his team aimed to involve locals to monitor their presence.

Local fishermen claimed they were familiar with the mammal even before the conservationists detected their presence.

Abdul Hadi, 63, said the Irawaddy dolphins often appeared in the 1990s alongside sailing boats. However, their appearance has decreased in the past 10 years.

“Irawaddy dolphins were believed to be able to give clues about the weather or the presence of fish and shrimp. If they swam closer to the coastal area, it meant there was a high tide or a storm so we didn’t sail. Their appearance also meant there were a lot of fish and shrimps,” Hadi said.

Environmental degradation triggered by local industry is another challenge facing conservation efforts in the region. Syarif, however, confirmed that the Irawaddy dolphins in the area were not affected by the recent Balikpapan oil spill.