Ecology and eco-system of Piha

Marine Environment at PIha

Marine environment

Marine ecology - check out this site: www.seafriends.org.nz

Set net ban to save the Hector's dolphin

On 16 August 2001 the Ministry of Fisheries announced a ban on set netting by commercial or recreational fishermen in an area along the western coastline of the North Island that is home to the Hector's dolphin. The area extends from Maunganui Bluff (north of Dargaville) to Pariokariwa Point (north of New Plymouth) and extends four nautical miles out to sea. The harbours are not included. A comprehensive observer programme will monitor all trawlers and Danish Seine vessels fishing in the area for the next five years. There will be an independent observer on all trawl and Danish seine vessels operating within the four nautical mile restricted area. Trawling and Danish seining are not banned, but the Minister of Fisheries, Pete Hodgson, says that this will be monitored.

The North Island Hector's dolphin is one of the rarest marine mammals in the world, with only about 100 surviving on the West Coast of the North Island, between Taranaki and the Kaipara Harbour. It is special because there are so few and it is the smallest dolphin in the world. Adult females seldom grow past 1.5 metres and the males are smaller. Because they reproduce slowly, it is expected that the population of 100 would only increase by only about four each year.

This gentle creature, unlike other dolphins, does not cruise widely, preferring to stick closely to the Coast, especially areas of turgid water around harbour entrances. They make their homes in particular areas and do not stray too far, Surfers and swimmers beyond the breakers at Piha sometimes see pods of these dolphins which like to fraternise with humans sharing their domaine.

Hector's home loving ways make it more vulnerable to human activities in the same waterways. The worst threat is drowning after becoming tangled in gill nets set by commercial and recreational fishermen, although it is thought that some young dolphins are killed by direct hits by boats, and that their health and fertility is affected by pollution flowing from harbours.

The Hector's dolphin is distinctively marked grey, white and black, with rounded black dorsal and pectoral fins. They live till they are about 20, but the females do not start to breed until they are 7 to 9 years old. They usually only produce a single calf every two or three years.

It is genetically distinct from the South Island species of which there are about 4,000.

Auckland University researcher Kirsty Russell has made the Hector's dolphins her special area of study. She is looking at the dolphins' diet, by looking at the stomach contents of dead specimens.

To get up-to-date news on the Hector's dolphin visit the World Wildlife Fund special web site www.hectorsdolphin.org.nz.

Sightings and strandings of Hector's dolphins can be reported by calling 0800 HECTORS or through the web site. WWF relies on local communities to report all sightings.

Set-back for survival of Hector's dolphins

The High Court in Auckland has scrapped a government ban on set-netting on the West Coast, established to protect the severely endangered Hector's dolphin.
The ban was announced in August 2001 by the Minister of Fisheries Pete Hodgson.
In the High Court Justice Young ruled that the minister had been 'wrongly advised' by his officials about the dolphin's sustainability. The minister had used a formula called MALFIRM to predict growth of the species. The judge said this formula could be used to calculate growth but not extinction.
The Northern Inshore Fisheries Company reacted to the decision by saying that commercial fishing had little effect on the dolphins' ability to maintain and rebuild numbers.
Following this judgment, set-netters are free to continue working the West Coast.
There are only about 100 Hector's dolphins on the west Coast of the North Island.

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	Marine environment Marine ecology - check out this site: www.seafriends.org.nz

	Set net ban to save the Hector's dolphin On 16 August 2001 the Ministry of Fisheries announced a ban on set netting by commercial or recreational fishermen in an area along the western coastline of the North Island that is home to the Hector's dolphin. The area extends from Maunganui Bluff (north of Dargaville) to Pariokariwa Point (north of New Plymouth) and extends four nautical miles out to sea. The harbours are not included. A comprehensive observer programme will monitor all trawlers and Danish Seine vessels fishing in the area for the next five years. There will be an independent observer on all trawl and Danish seine vessels operating within the four nautical mile restricted area. Trawling and Danish seining are not banned, but the Minister of Fisheries, Pete Hodgson, says that this will be monitored. The North Island Hector's dolphin is one of the rarest marine mammals in the world, with only about 100 surviving on the West Coast of the North Island, between Taranaki and the Kaipara Harbour. It is special because there are so few and it is the smallest dolphin in the world. Adult females seldom grow past 1.5 metres and the males are smaller. Because they reproduce slowly, it is expected that the population of 100 would only increase by only about four each year. This gentle creature, unlike other dolphins, does not cruise widely, preferring to stick closely to the Coast, especially areas of turgid water around harbour entrances. They make their homes in particular areas and do not stray too far, Surfers and swimmers beyond the breakers at Piha sometimes see pods of these dolphins which like to fraternise with humans sharing their domaine. Hector's home loving ways make it more vulnerable to human activities in the same waterways. The worst threat is drowning after becoming tangled in gill nets set by commercial and recreational fishermen, although it is thought that some young dolphins are killed by direct hits by boats, and that their health and fertility is affected by pollution flowing from harbours. The Hector's dolphin is distinctively marked grey, white and black, with rounded black dorsal and pectoral fins. They live till they are about 20, but the females do not start to breed until they are 7 to 9 years old. They usually only produce a single calf every two or three years. It is genetically distinct from the South Island species of which there are about 4,000. Auckland University researcher Kirsty Russell has made the Hector's dolphins her special area of study. She is looking at the dolphins' diet, by looking at the stomach contents of dead specimens. To get up-to-date news on the Hector's dolphin visit the World Wildlife Fund special web site www.hectorsdolphin.org.nz. Sightings and strandings of Hector's dolphins can be reported by calling 0800 HECTORS or through the web site. WWF relies on local communities to report all sightings. Set-back for survival of Hector's dolphins The High Court in Auckland has scrapped a government ban on set-netting on the West Coast, established to protect the severely endangered Hector's dolphin. The ban was announced in August 2001 by the Minister of Fisheries Pete Hodgson. In the High Court Justice Young ruled that the minister had been 'wrongly advised' by his officials about the dolphin's sustainability. The minister had used a formula called MALFIRM to predict growth of the species. The judge said this formula could be used to calculate growth but not extinction. The Northern Inshore Fisheries Company reacted to the decision by saying that commercial fishing had little effect on the dolphins' ability to maintain and rebuild numbers. Following this judgment, set-netters are free to continue working the West Coast. There are only about 100 Hector's dolphins on the west Coast of the North Island.
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