The Maui’s Dolphin (Cephalorhynchus hectori maui) is one of the world’s rarest and smallest cetaceans on Earth. It can only be found exclusively in the shallow coastal waters of New Zealand. One full grown animal may measure in at about 1.4 meters and weight in at around 50 kilograms. In fact, these animals are no bigger than a small human child. Maui Dolphins are easily distinguished by their black facial markings, short stocky bodies, and their mouse ear-shaped dorsal fins.
Identified as a subspecies of the Hector’s dolphin in 2002, Maui’s Dolphins are found in shallow coastal waters off New Zealand’s North Island along it’s western shores. The majority of the sightings of these animals have mainly been between Manuka Harbor and Raglan Harbor, North Island, NZ. Maui’s tend to swim close to the shore line, making them more at risk of becoming entangled in fishing nets. During the Southern Winter months (June-September), the dolphins are distributed between the shoreline and 7.5 kilometers offshore while in the summer months (December-March), they are usually seen much closer to the shore.
Maui’s Dolphins live in small pods that range in size from two to eight animals. Pod membership is usually fluid because pod mates mix freely from other pods.These animals are well known for their playful and acrobatic behaviors such as blowing bubbles, playing with seaweed, or surfing the waves. However, they do spend most of their time foraging for food underwater. They have been known for taking short dives for up to 90 seconds. During that time, the animals may be finding or catching fish and squid by using echolocation in mid-water. However, they have been sighted feeding near the surface of the water.
Females do not breed until they are at least 7-9 years of age. Although the gestation period for these animals in not known, calves are said to be born around the southern spring and early southern summer, from November to mid-February. Calves will stay with their mother for up to two years and begin to feed on fish for the first time when they are at least six months old. Over the course of her 20-year lifespan, a mother Maui dolphin may give birth to only four calves, but that is not enough to keep a dangerously low population of only 100 dolphins growing beyond %2 due to the ever increasing deaths by human impact.
Because they live close to shore, Maui’s dolphins are at great risk of dying by entanglement and boat strikes. Deaths by entanglement in both recreational and commercial gill and trawl nets have been recognized by both New Zealand’s Ministry of Fisheries and the New Zealand Department of Conservation as the biggest threat the animals face. What happens is the dolphins would be detecting their prey using echolocation when the fish passes the nets, the dolphins simply, just get to close to them because these fishing nets are not picked up by the echolocation and thus, the dolphin may try to swim through it as a way to find prey before getting themselves entangled. Once entangled, they cannot release themselves from the nets, and thus, they drown within a matter of minutes.
What is being done to protect both the Hector’s and Maui’s Dolphins?…….
- Long term radio tag surveys are helping researchers understand their daily migration patterns and harbor uses
- Researchers have conducted the relationship between boats, human swimmers, and dolphins to determine the long term impact it has on animals.
- New Zealand’s Department of Conservation has encouraged the public to call their dolphin sighting hotline if they site either a dead or live dolphin.
- Educating the public about the plight of these endangered dolphins