Part of complete coverage on
Rare dolphins boosted by sea sanctuary
March 28, 2012 -- Updated 0403 GMT (1203 HKT)
Hector's dolphins are one of the rarest and smallest species on the planet.
- Area off New Zealand 's east coast a haven for rare dolphins
- No-fish zone has helped survival rate of Hector's dolphins
- Study was conducted over 21 years
(CNN) -- Coastal areas that ban fishing can provide havens for endangered wildlife, according to a new report.
Findings from a research project conducted over 21 years and published in the "Journal of Applied Ecology" revealed that a marine sanctuary off the coast of Christchurch, New Zealand has significantly improved the survival of Hector's dolphins .
They are one of the rarest species of dolphins, endemic to the waters around New Zealand, with only around 8,000 animals thought to be left in the wild.
Marine Protected Areas (MPA) have long been advocated as a way to protect sea mammals, but the New Zealand project is the first to confirm this.
Marine Protected Areas work, but they have to be large enough in order to be effective.
Liz Slooten, University of Otago
"This study provides the first empirical evidence that Marine Protected Areas are effective in protecting threatened marine mammals," said Liz Slooten of the University of Otago.
Since the MPA was designated, the dolphin's survival has increased by 5.4%, according to the report.
Covering 1,170 km2 of sea off New Zealand's South Island, Banks Peninsula Marine Mammal Sanctuary was designated in 1988 to prevent the dolphins being killed by gillnet and trawl fisheries.
Between 1986 and 2006, researchers conducted regular photo-identification surveys of Hector's dolphins, photographing 462 individual animals whose survival they studied.
"We can identify individual dolphins from their battle scars -- which range from small nicks out of the dorsal fin, to major scarring following shark attacks," said Slooten
"Estimating population changes in marine mammals is challenging, often requiring many years of research to produce data accurate enough to detect these kinds of biological changes."
The study also shows that to be effective, MPAs need to be sufficiently large.
"The take home message is that size matters. Marine Protected Areas work, but they have to be large enough in order to be effective," said Slooten.
Today's five most popular stories
Part of complete coverage on
January 21, 2013 -- Updated 0230 GMT (1030 HKT)
Patricia Wu looks at efforts to combat food waste in Hong Kong.
January 14, 2013 -- Updated 0233 GMT (1033 HKT)
CNN's Pauline Chiou goes to Hong Kong's annual toy fair to find out about the growing market for eco-friendly toys.
December 31, 2012 -- Updated 0415 GMT (1215 HKT)
CNN's Liz Neisloss reports on a roof that is only a sample of the greening of Singapore's skyline.
December 19, 2012 -- Updated 0216 GMT (1016 HKT)
A dam project in Cambodia could destroy livelihoods and ecosystems, says Conservation International
December 18, 2012 -- Updated 0322 GMT (1122 HKT)
Shipping lines, port authorities and technology companies are taking the initiative to go green and reduce costs.
December 10, 2012 -- Updated 0206 GMT (1006 HKT)
Less than 20 miles from Singapore's skyscrapers is a completely different set of high-rise towers.
December 6, 2012 -- Updated 1104 GMT (1904 HKT)
The Pitcairn Islands might only have 55 human inhabitants, but the waters surrounding them are teeming with marine life.
December 3, 2012 -- Updated 0322 GMT (1122 HKT)
Biofuel made from sugar cane waste in Brazil could revolutionize the global energy industry.
November 26, 2012 -- Updated 0258 GMT (1058 HKT)
Many believe that fuel-cell cars will overtake electric vehicles in the near future.
November 19, 2012 -- Updated 0820 GMT (1620 HKT)
Modern and sustainable buildings in the UAE are taking cues from an ancient Arabic design tradition.
November 12, 2012 -- Updated 0409 GMT (1209 HKT)
One man's artistic vision is distracting divers from Cancun's threatened underwater ecosystem.
November 12, 2012 -- Updated 1746 GMT (0146 HKT)
Lake Victoria, Africa's largest lake, has been plagued by water hyacinth plants for over two decades.
Just how much are natural wonders like the Great Barrier Reef worth in monetary terms?