World’s Rarest & Smallest Dolphin On Verge of Extinction at Just 55
The parent species of the Maui dolphin - Hector's dolphin JShook / Wikimedia Commons

The number of last surviving Maui's dolphins, the world's rarest and smallest marine dolphins, is estimated to be around 55 that call for urgency in conserving the endangered species from extinction, a new find suggests.

The survey by New Zealand's Department of Conservation (DOC) released in mid of March revealed that the number of dolphins decline to almost half since they were last recorded at 111 in 2005.

Found only off the northwest coast of North Island in New Zealand, the Maui's dolphins are a sub-species of Hector's dolphin measured at about 1.4 meters in length.

These dolphins are classified as Critically Endangered by the IUCN Red List of Endangered Species and could face immediate extinction, according to the NABU International Foundation for Nature.

Human activities, mainly fishing, pose a great risk to the dolphins as Maui's dolphins thrive in shallow waters up to 100 meters deep and could get caught in fishing nets easily.

Every day the animals are exposed to gill and trawl nets carries a risk we can't afford. If ever there was a time to act, it is now, NABU International's Head of International Species Conservation, Dr. Barbara Maas, said in a statement.

Mass said that female Mau's dolphins cannot breed until they are 7-9 years old. Plus they produce one calf every 2-4 years. Therefore, the chances of increase in population is very low as against the higher rate of increase in marine tourism, vessel traffic, mining, coastal development, pollution, sedimentation, oil spills, plastic bags, marine farming and climate change that pose a significant threat to the dolphins.

A population of 55 adults means that just over 20 breeding female Maui's dolphins survive. Even more Maui's dolphins will have died since the research was carried out in 2010/11- we know of at least two in the past six months.

The conservation organizations have urged the New Zealand government to take immediate emergency measures to save the last surviving Maui's dolphins by declaring the full range of Maui's dolphins a Marine Reserve, or by prohibiting the use of gillnets and trawling in the dolphins' range along a 100m depth contour.