Operation Ark to save species on the brink

An initiative that could result in predator control programmes larger than anything previously attempted by the Department of Conservation is being developed to protect New Zealand's most threatened forest birds, Conservation Minister Chris Carter announced today. The initiative, called Operation Ark, is designed to blunt the impact of sudden plagues of rats and stoats that in the past two years have devastated the populations of two bird species, the orange-fronted kakariki and the mohua (yellowhead).

Orange-fronted kakariki have plummeted in numbers from 700 to about 150 since 2000 and are now found in just three valleys in North Canterbury. Mohua have also halved in numbers to about 5000 birds in the same period, and have disappeared completely from two of the areas where they were previously found.

"We have had two severe stoat plagues in succession in our forests, and one rat plague. It is unlikely the orange-fronted kakariki will survive further plagues, and despite DoC's best efforts we have yet to establish a captive breeding programme to fall back on. We must act decisively," Mr Carter said.

"Operation Ark will ensure that we can respond very aggressively to future predator plagues and protect these birds and others under similar threat, in their natural habitat."

Thanks to recent advances in botany and DoC's growing understanding of alien predators, it is now possible to predict when some predator plagues are likely to occur. For instance, stoat plagues are frequently associated with years in which beech trees fruit unusually heavily. These can be predicted up to six months in advance.

Operation Ark will involve more research of plague triggers, particuarly in relation to rat plagues which are poorly understood. This research will feed into the development of systems to improve plague predictions and link them to a rapid response regime of predator control.

The initiative will involve identifying up to 10 key sites or arks in beech forests throughout the South Island, which are home to severely threatened species, such as the orange-fronted kakariki, mohua, whio (blue duck) and peka peka (long-tailed bat). Each of these sites are likely to be at least 10,000 ha in size and will be intensively monitored. Selection of them will be completed by November.

By September 2004, DoC plans to have prepared and obtained all the necessary resource consents, licences and approvals for use of a full complement of predator control in these areas. Supplies of traps and poisons, such as 1080, will also be secured.

"Current information suggests that we are not going to have a heavy fruiting year next year reducing the likelihood of a predator plague. This gives us a little breathing space, " said Mr Carter.

"We must use this time productively.The idea of Operation Ark is to develop a full arsenal of plague responses which can be used at short notice to create safe zones in times of crisis for threatened species.

"The beauty of this initiative is that it will give DoC the flexibility to use all its weapons to combat predators, or select just a few depending on the severity of the plague they are dealing with and the species they are trying to protect. That flexibility does not exist at the moment."

In the habitat of the orange-fronted kakariki, for instance, DoC is likely to continue with its intensive programme of trapping, and introduce special poison bait stations in plague years, and possibly use aerial 1080 to create a buffer around the birds.

Because of the size of the orange-fronted kakariki's habitat, this will mean a larger predator control programme than anything else DoC has attempted. In a worse case scenario, Operation Ark may require similar programmes in a number of areas in one year.

"Obviously, Operation Ark could be expensive, " Mr Carter said.

"In years in which plagues occur in only one or two priority areas, the costs will not be out of the ordinary. But if New Zealand faces another predator plague in its beech forests of the magnitude of 2000 and 2001, the costs of a powerful response could rise substantially.

"I will be working with the department to build this emergency response capacity in to Vote Conservation as a key component of the government's Biodiversity Strategy. The consequences of not responding comprehensively will mean the inevitable loss of yet more of our fragile bird species," Mr Carter said.

© Scoop Media