Can we pull Maui's dolphins from the brink of extinction?
The world’s smallest and rarest dolphin species is on the verge of extinction.
New research suggests that the population of Maui’s dolphin, native to the waters off New Zealand's North Island, has fallen to an all-time low of fewer than 50 individuals, with only 10 to 12 breeding females left. Scientists and conservationists are once again urging the New Zealand government to expand measures to prevent dolphins from dying in fishing nets – the main reason the population has declined by 97 percent since the 1970s, according to the German conservation group NABU.
"It's a wake-up call, it's shocking," says Dr. Barbara Maas, NABU's head of endangered species conservation. The new figures, she adds, are a result of what she says is the New Zealand government's inadequate management response to what scientific research has for years been urging it to do.
“New Zealand has to abandon its current stance, which places the interests of the fishing industry above biodiversity conservation, and finally protect the dolphins’ habitat from harmful fishing nets, seismic airgun blasts, and oil and gas extraction,” Dr. Maas told the BBC.
Otherwise, the dolphin’s extinction would be “a matter of when, not if,” she told the British news service.
Maui’s dolphin, scientific name Cephalorhynchus hectori maui, is a subspecies of Hector’s dolphin and is found in coastal waters up to a depth of 100 meters on the west side of New Zealand’s North Island. Solidly built, with a sloping snout and a rounded, or “mickey mouse shaped,” dorsal fin, the dolphin is the smallest in the world, measuring about 4 to 5 feet in length and weighing a little over 100 pounds as an adult, according to the WWF.
Females have a low reproductive rate, breeding just fast enough to replace those dolphins that die naturally — which explains why the species is struggling to recover from human-induced deaths, the WWF noted. In 2013, the species was listed as critically endangered by the International Union for Conservation of Nature (IUCN). Today, Maas estimates there are 43 to 47 individuals, a distinct drop from 59 dolphins in 2010.
If allowed to become extinct, she says, Maui's dolphin would mean the loss of an important predator in the local ecosystem, which would affect the rest of the food chain.
“Maui's dolphins ... are building blocks of biodiversity," Maas says. "They are not ornaments that are just there and can be removed.”
Maui’s dolphin faces a number of risks, including pollution, tourist activity, and seismic testing, conservationists have said. The last has been heavily debated by marine mammal advocates and oil and gas companies, who employ seismic surveys to determine whether oil and gas reservoirs exist beneath the ocean floor.
Groups such as the Petroleum Exploration and Production Association of New Zealand have said that their methods are tested and regulated, and do little, if any, harm to the environment. Conservationists, on the other hand, have argued that seismic testing causes temporary or permanent hearing loss in dolphins, which in turn leads to stranding or death.
But the biggest problem Maui’s dolphin faces are trawl fishing and gillnetting, both popular commercial and recreational enterprises in New Zealand. These activities employ large, fine nets to trap fish – nets responsible for more than 95 percent of Maui’s dolphin mortalities, according to a 2012 study by a panel of experts appointed by the New Zealand government.
“It’s a very fine nylon mesh, and the dolphins can’t detect this net, so they get tangled in it and drown,” Milena Palka, a marine advocate for WWF New Zealand, told the New Zealand Herald.
In response to the Maui’s dolphin crisis, the New Zealand government in 2007 developed the Hector's and Maui dolphin threat management plan, which sought to restrict the movement of commercial and tourist vessels and to establish sanctuaries in the species’ natural habitat. The plan would bolster New Zealand’s 1978 Marine Mammals Protection Act, which gave the country’s Department of Conservation the mandate to protect and administer marine mammals and their sanctuaries.
Critics, however, have said that the government’s efforts are inadequate.
In her latest study, to be presented at the International Whaling Commission (IWC) Scientific Committee meeting in San Diego this week, Maas wrote that New Zealand had promised to increase conservation efforts in response to last year's IWC recommendations. The committee had urged the government to expand protected waters, ban trawl fishing and gillnetting throughout the species’ habitat, and commit to specific timelines and targets with regards to the dolphin’s conservation.
“The committee reiterates its extreme concern about the continued decline of such a small population as the human-induced death of even one dolphin would increase the extinction risk for this subspecies,” according to the IWC.
But the dolphins' continued decline reveals a lack of political will on the part of the New Zealand government, and represents the problem that conservation as an issue faces on a global scale, Maas says. It says much about humans as a species if, in a country like New Zealand, we can't save as charismatic an animal as the dolphin even after decades of research telling us what to do, she adds.
She compares the survival of the world's ecosystems to the block game Jenga: “We pull out one, we pull out another ... eventually, we crash.”
The deadline for the dolphins’ extinction has been debated, but NABU, the German conservation group, has said that if the status quo is maintained, the species could be gone by 2031. If concrete steps are taken, however, and human-caused deaths are cut to zero, the dolphins’ numbers could be up to 500 individuals within about 90 years.
“They are not doomed to extinction,” Dr. Maas told the BBC in 2013. “Genetic variability is still high [and] they can bounce back, but saving them is a race against time.”