There are 32 species of dolphins found throughout the world. The Hector’s dolphin is the smallest oceanic dolphin with the Orca being the largest.
Where are they found?
The Hector’s dolphin is endemic to the coastal waters of New Zealand. The Hector’s dolphin is only found around the South Island of New Zealand and are fragmented into three populations. They have a territorial range of 52 kilometres. Akaroa Harbour and Banks Peninsula host roughly 1000 of these dolphins.
There is also a sub-species called the Maui dolphin which is only found in the North Island. The Hector’s and Maui’s dolphins are related to a similar species in South Africa and South America.
What they look like?
The Hector’s dolphins are distinguishable from other dolphins by their rounded black dorsal fin which is shaped like a Mickey Mouse ear. Their bodies are a distinctive grey, with white and black markings. They also have a short snout.
How long do they live?
Hector’s dolphins live to around the age of 20-25 years old, which is similar to humans living until 85-90 years old.
How big are they?
Adult Hector’s dolphins don’t often exceed 1.4 m in length and weigh between 40-60 kg. The males are slightly smaller and lighter than females. At birth, Hector’s dolphin calves have a total length of around 60-80 cm and weigh 8-10 kg.
What do Hector’s dolphins eat?
Hector’s are not too fussy about what they eat, and hunt more to the size of the prey rather than their actual species. They make frequent short dives to find food, such as flounder, red cod, crabs, kahawai, mackerel and squid. The Hector’s dolphins can hold their breathe up to 3 minutes when diving but generally only hold it for 1 minute..
How do they know where they are going and what is around?
The Hector’s eye sight is only slightly better than humans. They use echo-location to judge distances, locate their prey, and judge how fast it is moving. It is like seeing with sound. They send out high frequency clicking noises and when the sound strikes an object it bounces back, and the dolphin can tell by listening what the object is. In familiar areas, their echo-location is often ‘turned off’, which means they cannot always detect dangers.
What do they do all day?
Hector’s dolphins spend their day between feeding and play. They love to surf on waves; play with seaweed and balance sticks on their snout. They are incredibly friendly and inquisitive creatures, which explains why they like to get up close to boats. Sometimes we wonder who is looking at who.
How did they get their name?
The Hector’s dolphin was named after Sir James Hector, who was the curator of the first Colonial Museum in Wellington (now named Te Papa). Sir James Hector examined the first dolphin specimen that was found. Sir James lived from 1834 to 1907, and was the most influential New Zealand scientist of his time.
How many are there?
The last 40 years have seen a rapid decline in the Hector’s dolphins numbers. In the 1970s their population was around 30,000. Today there are fewer than 8,000 dolphins remaining. The even rarer sub-species of Hector’s dolphin, the Maui’s dolphin, is under even greater threat. Their population is now estimated to be less 55 dolphins.
What are their threats?
The Hector’s dolphins are at risk from human-induced threats that include boat strike, pollution and climate change. The biggest single known threat is from fishing. Fishing related threats include entanglement in set-nets, trawl nets, drift nets and crayfish pot lines. The reason being the dolphin can not detect the fine mesh in gillnets and trawl nets and get stuck as they can not reverse. Instead of drowning they asphyxiate.
The Banks Peninsula marine mammal sanctuary in Canterbury was established in 1988 primarily to reduce set-net deaths of Hector’s dolphins in the area. The Marine Mammals Protection Regulations were introduced in 1992 to control marine mammal tourism activities. Set-net controls were introduced to Canterbury in 2002 and in the west coast North Island in 2003.
DOC, in a joint initiative with the Ministry of Fisheries developed a Draft Threat Management Plan released in 2007 which we here at Akaroa Dolphins were proud to be a part of.
Since then additional fisheries restrictions have been implemented along with four new marine mammal sanctuaries and alterations to the Banks Peninsula marine mammal sanctuary. Research and scientific studies continue to increase our knowledge about each sub-species ecology, conservation status, life history and threats. Improved management practices are continually being sought for these dolphins in an attempt to ensure their survival into the future.
What can we do to help protect Hector’s Dolphins?
When joining us on one of our cruises part of your fare goes towards dolphin research and education. You can also support the Department of Conservation as they find new ways to protect the species, including more marine mammal sanctuaries, which will stop dolphins being killed in set-nets. Visit the Department of Conservation to learn more about New Zealand’s Marine Mammal Sanctuaries.
If you own your own boat or are a passenger, ask the driver to slow down to avoid turning suddenly when a dolphin pod is near. Do not chase the dolphins or try and round them up. Sometimes if you simply stop the boat the dolphins will come and see you. Avoid using set- nets, also called gillnet, close to shore where the dolphins are most common. If you ever see a Hector’s Dolphin stranded on the beach contact either the Department of Conservation of Project Jonah immediately. See below for their contact numbers.
• DOC Stranding Hotline: 0800 DOC HOT (0800 362 468)
• Project Jonah Stranding Hotline: 0800 4 WHALE (0800 4 94253)
Through WWF- New Zealand, you can ‘adopt’ a Hector’s dolphin and help the species survive. To find out more visit www.wwf.org.nz