Sea change needed in marine protection

Octopus and paua off the Otago coast. Photos by Andrew Penniket and Ben Jaquiery.
Octopus and paua off the Otago coast. Photos by Andrew Penniket and Ben Jaquiery.

AndrewPenniket asks: is Otago the next province in line for marine reserves?

Next year marks the 40th anniversary of the Marine Reserves Act 1975.

There are now 38 marine reserves in New Zealand, from cold Campbell Island to the subtropical Kermadec Islands.

Fiordland alone has 10, but Otago still has none of these valuable assets - the only region without any.

Why are marine reserves important, and what are their benefits?

The reason marine reserves were first created was to allow research that was not possible in fished areas.

How could you truly study a fish population if every year most of the adults were being caught, as with snapper in the Hauraki Gulf?

By closing an area to all fishing, marine reserves have made it possible to get a handle on vital population parameters such as growth rates and longevity.

Marine reserves also allow the study of marine ecosystems.

By protecting an area and then comparing the trends of different species - for example, kina, crayfish, paua and cod - it is possible to build up a picture of how the species interact.

This is essential if we are to manage fisheries in a sustainable way.

Marine reserves also have an important role in keeping fisheries healthy.

Most of our fished species only get a couple of years' breeding before they reach the size at which fisheries regulations allow them to be taken.

For example, a crayfish starts breeding at about six years old, but can be caught and kept at about eight years old.

In a marine reserve, that same crayfish may live to 40, 50 or even 60 years or more, giving an extra 30 plus years of reproduction - producing larvae that will float along the coast to repopulate fished areas.

Moreover, as a crayfish gets older it has an almost exponential increase in the number of eggs it produces.

A first-time breeder may have 20,000 eggs but a large fully mature crayfish can have 500,000 eggs. That's a 25-time increase with size.

Similar relationships between age, size and egg production are true for paua, blue cod, moki and other fished species.

So that means big old animals are extremely valuable. But at the moment, in Otago, there is not a single place where they are protected and can reach a large size unmolested by humans.

Marine reserves offer that protection and act as insurance policies against bad years of larval settlement because of the likes of bad weather, El Nino climate effects or current changes in the sea.

Perhaps the most exciting benefit of marine reserves is their value for education.

Every year more than 200,000 people visit Goat Island Marine Reserve, one hour north of Auckland.

They get to see giant old snapper and crevices full of large crayfish and they come away with a better understanding of what the sea is really like.

Pioneer diver and author Wade Doak has raised the concept of ''wet libraries''. He says every school has the right to have playing fields, classrooms and school libraries.

And he sees marine reserves as being wet libraries, where children can go to learn about the sea. Supporters of the concept say every school in New Zealand should have easy access to a ''wet library''.

Those are some of the benefits Otago is missing out on (there are big spin-offs for tourism too), but the good news is moves are under way to fix this problem.

The Department of Conservation, in conjunction with the Ministry of Primary Industries, has set up a Marine Protected Area (MPA) Forum with the aim of establishing marine reserves in Otago and Southland.

This may be our only opportunity to get some marine reserves, so now is the time to get involved in the MPA process - attend meetings and write submissions.

New Zealanders take pride in our glorious country, and in Otago we have some of the most beautiful parks and reserves in the land.

Now it is time to have some in the sea. Andrew Penniket describes himself as an underwater photographer and conservationist.

 

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