NEW ZEALAND LOOKING AT WORLD FIRST IN PEST ERADICATION

On 25 July New Zealand's Primary Industries ministry and Department of Conservation approved a nationwide strategy that will see all exotic pest animals eradicated from the country by 2050. 

Possums, rats, ferrets and stoats will be initial targets for this ambitious plan, which by its overarching scale is set to be a world-first for any pest eradication scheme.

A new company, Predator Free New Zealand Ltd, will partner and fund initiatives by the Maori community, other conservation groups and the private sector in a coordinated effort to sweep out every introduced animal, leaving nothing to continue to breed on.

By its small size and isolation New Zealand evolved over millions of years with a relatively low number of wildlife species and bats the only mammals. The birds, evolved in balance without terrestrial predators, now struggle against an estimated 25 million annual deaths by exotic pests (Maggie Barry, NZ Conservation Minister) while the unique co-evolved native plants are equally vulnerable to extinction by possums and rats.

Australian possums, with needle-sharp claws and teeth, feed on virtually anything from flowers to meat, with no tasty plant or nestling a match for their strength and fearless habits. Ferrets and stoats, similar in size and survival equipment, also carry bovine tuberculosis.

Now the people and government want to take back their environment, restore its natural balance, and have their homeland back in the shape it was before ships and irresponsible immigrants spread pets and pests into an environment unsuited to cope with them.

However, as with all governments nothing happens quickly. The first part of this initiative, plus a good swag of its funding, will be absorbed by research, under a Biological Heritage National Science Challenge, to develop technology necessary to achieve this ambitious goal.

Meanwhile, as with Australia's appalling occupation by cats and cane toads, it is assumed that in New Zealand a few dedicated, unfunded volunteers will continue to strive to save what is left of a rapidly disintegrating and disappearing natural heritage - for as long as they are able to do it.

- Patricia Edwards

 This article was originally published in the VOICES FOR THE EARTH column in The Daily Examiner on September 5, 2016

CANE TOADS IN THE CLARENCE VALLEY

Cane toads  were introduced to the north Queensland sugar cane area in the 1930s in the mistaken belief that they would eradicate the cane beetle.  Since then they have been steadily spreading south and west. To the west they have moved across the Queensland savanna into top end of  the Northern Territory ( including into Kakadu National Park) and  further west  into the Kimberley region in the north of Western Australia. To the south they have moved as far as the northern coastal section of the Clarence Valley in the NSW Northern Rivers. There are large populations in and around Yamba and Brooms Head.

Cane toads (Rhinella marina) are poisonous through their life cycle. As these introduced pests advanced they brought devastation to native wildlife which sought to prey on them in the areas they have colonised.  Goannas, snakes, freshwater crocodiles, quolls and dingoes are some of the native species which have died as a result of the toad's poison.

Efforts to eradicate the cane toad have been under way in the Clarence Valley for a number of years.

A community group, Clarence Valley Conservation in Action (CVCIA) Landcare, has been collecting and disposing of cane toads in the Clarence.  The work of these volunteers has been assisted by the National Parks and Wildlife Service, North Coast Local Land Services and local ecologist Russell Jago.

From July 2015 to May 2016 25,000 cane toads have been removed from the Clarence Valley.  71% of these came from Yamba, 17% from Brooms Head, 7 % from Chatsworth Island and 5% from other areas.  In addition 120,000 cane toad tadpoles have been trapped in the same period.  Trapping of tadpoles is a recent development and one it is hoped will cut toad numbers breeding in farm dams.

For further information on the cane toad in Australia refer to the  Australian Museum

Photo: Clarence Valley Conservation in Action Landcare

SAVING NORTHERN TERRITORY QUOLLS FROM CANE TOADS

The Northern Quoll (Dasyuris hallucatus) , a carnivorous marsupial, is the smallest of the four Australian quoll species.  It is listed as endangered under the federal Environment Protection and Biodiversity (EPBC) Act.  In the Northern Territory it was listed as critically endangered in 2012.

 Photo: Australian Wildlife Conservancy

Northern Quolls, once very common in the northern part of the Northern Territory, became critically endangered as feral cane toads[1] spread across the north. Twelve years ago quolls from the Darwin and Kakadu areas were collected and relocated to two cane-toad free islands with suitable habitat off north-east Arnhem Land.  They have flourished there and now number in the thousands.

Some of these quolls are now to be returned to the mainland where they will be trained to leave cane toads alone. Initially they will be re-housed in the Territory Wildlife Park where they will be fed on cane toad sausages.  This food, which will smell like cane toad, will make the quolls ill.  The scientists conducting this conditioned taste aversion program expect that the quolls will learn to reject the toads as a food source. After the training they will be released in the Mary River district of Kakadu National Park which contains suitable quoll habitat.

The animals which are released will be closely monitored so that the success of the program can be gauged.

An earlier trial of this taste aversion in Kakadu led to the survival of some quolls and the passing on of the cane toad aversion to baby quolls – which gives the scientists hope that quolls can be successfully reintroduced to areas where cane toads are living.

There are also plans to use the cane toad sausages with wild quolls in the Kimberley area in the hope this will lead to their survival in spite of the toad invasion.

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[1] Cane toads (Bufo marinus), natives of Central and South America, were introduced to Queensland in 1935 in the mistaken belief that they would control pest beetle in sugar crops.  Since then they have moved south along the east coast with established populations as far south as the Clarence Valley (Yamba and Brooms Head) in NSW and west across the Queensland savanna into the Northern Territory and across into northern Western Australia. They have had a devastating impact on native wildlife which has eaten them  (e.g. goannas and quolls)