Another moth gets out

By ANNE BESTON

A second Australian moth pest spread throughout South Auckland for more than a year after it was detected because it was outside the area biosecurity authorities were searching.

Authorities are battling an infestation of Australian painted apple moth in West Auckland.

Now the Ministry of Agriculture and Forestry has widened its search for the gum leaf skeletoniser over South Auckland.

MAF said yesterday it did not cast its net wide enough for the skeletoniser when it was discovered in Onehunga in late 2001.

The moth was found in the Waikaraka Cemetery, and MAF drew up a 1km search area around that infestation.

Four more sites within a 30m radius were treated with insecticide and the area was monitored for a year before MAF discovered the skeletoniser had moved to another 11 sites, from Auckland International Airport to Manukau and across to the Tamaki River.

MAF director of forest biosecurity, Peter Thomson defended the original decision to limit the original search to a 1km radius.

"Information at the time suggested it was slow-moving and slow-breeding and everything we found was within 30m, so I can understand how those in charge at the time thought it was a reasonable place to stop," he said.

The gum leaf skeletoniser had only limited similarities to the painted apple moth, target of the Government's $90 million eradication programme in West Auckland.

The skeletoniser attacked only non-native eucalyptus trees, was a poor flyer and bred much more slowly than painted apple moth.

One of the reasons it took MAF more than two years to begin aerial spraying against painted apple moth was that the danger of the moth spreading was considered low.

The next steps against the skeletoniser would be "informed by lessons learnt from the painted apple moth operation", said Mr Thomson.

The Herald understands an aerial attack against the pest is unlikely.

Other options are to spray it on the ground or give up on eradication and try to control its spread.

Scientists, MAF staff and eucalypt growers will meet early next month to discuss the next move.