‘We rarely see them now’: how vulnerable are Vanuatu’s dugongs?

OOn a bright spring day, the sun dances over the water of Havana Bay on Efate Island in Vanuatu. Beneath the surface, pockets of sea grass that can almost be seen from shore sway in the current. It is here, if they are lucky, that onlookers may spot a dugong gliding in the shallow water, circling the seagrass meadows on which they feed.

“It’s great to see them swimming and grazing from the sea grass in front of the resort,” says Greg Pechan, owner of a local hotel, the Havannah, which sits at the top of the bay. Pointing across the jetty to the Pacific Ocean, he says Vanuatu’s marine life is a big draw for visitors to the Melanesian country.

Light gray in color, dugongs, sometimes known as “sea cows” and whose closest relatives are freshwater turkeys, can grow up to four meters long and weigh up to 400 kg (900 lb). They are a “friendly species” and respected by the islanders, says Heidi Joy, a marine science student from Efate.

A few years ago, it wouldn’t be unusual for Joy, who lives near Havannah Bay, to spot a dugong in the morning and then again at sunset. That has changed since then, she says. “We rarely see them now.”

Dugongs are considered vulnerable to extinction by the International Union for Conservation of Nature. However, the exact number that roam Vanuatu’s waters is unknown, and this uncertainty is hampering conservation efforts, experts say.

“Many studies have been done where you have large dugong populations in large seagrass meadows [such as] Australia or Abu Dhabi, but we have a different dugong population. We have small groups or individuals,” says Christina Shaw, CEO of the Vanuatu Environmental Science Society.

She says a national assessment of dugongs and seagrass in Vanuatu is urgently needed, so it is clear how many there are, where they are and whether they are suffering in the same way as in other parts of the region.

In 2023, the status of neighboring New Caledonia’s population was downgraded to “endangered” while East African dugongs became “critically endangered”. “In these two areas, there is enough information to make a regional assessment,” says Shaw.

In Vanuatu, however, only one aerial survey – in 1987 – has been conducted to assess national distribution, abundance, cultural significance and threats, according to Helene Marsh, an emeritus professor of environmental science at James Cook University.

Dugongs worldwide are threatened by net fishing, boat traffic, coastal development and hunting.

In Vanuatu, dugong meat was considered a source of protein, their oil was used for cooking and other parts were turned into handicrafts.

But since the 1980s, some islands have introduced local bans known as taboo, which mandates their protection. In 2010, the government also signed the Convention on Migratory Dugong Species memorandum of understanding, committing it to protect manatees and the seagrass they eat. That means poaching is now rare, says Shaw.

Instead, another predator threatens the dugong: the climate crisis. On a spring evening in Efate, rain falls relentlessly into the evening, turning the ocean a dark green. It is storms like this that are becoming more common, along with storms and cyclones, that damage the sea grass so vital to dugongs.

Vanuatu is located on the Pacific “Ring of Fire”, a tectonic belt of volcanoes and earthquakes, and a tropical cyclone region, making it prone to disasters. When these hit Vanuatu’s bays and beaches, the seagrass is swept away by strong winds, while rain and debris build up sediment on the water’s surface, drowning the seagrass from the sunlight it needs to thrive. It is estimated that 7% of the world’s seaweed is lost each year.

After twin cyclones Judy and Kevin hit in March 2023, seagrass meadows in Havana Bay were depleted.

Richard Leck, head of oceans at WWF Australia, says: “When this happens, dugongs have no choice but to move and sometimes have to go into deeper water, spend a lot more effort grazing on sea grass and when this happens they often get weakened and lose their condition very quickly.”

Since the cyclones, Joy says she rarely sees a dugong. On a boat across the bay to Moso Island, known to be frequented by dugongs, the waves give way to mangroves and none are visible near the surface. They are seen on diving excursions, Shaw says, but “you have to be lucky.”

As with dugongs, there is limited data on the distribution and status of seagrass in Vanuatu. That makes it difficult, says Shaw, to advocate for investment in conservation. “Funders don’t like paying for studies,” she says. “But how do we do it? [conservation] if we don’t know what it is?”