Dangerous Insects, Spiders, Invading New Zealand in Import Cargoes

Forest and Bird, Issue 303, 1 February 2002, Page 9

Dangerous Insects, Spiders, Invading New Zealand in

Import Cargoes

SIAN ROBINSON

~ epeated border ‘incursions by insect pests, including disease-carrying mosquitoes and venomous spiders, have highlighted the need for tougher biosecurity controls. ‘At present the hole in our border control is so big that a bus can get through it says Forest and Bird’s biosecurity awareness officer Karli Thomas. (She means this literally — last year a dirty bus slipped through border inspections completely.) Bif FA pt Among the unwanted invaders in 2001 were: e venomous live black widow spiders found on Californian table grapes four times in three months. e Fire ants, the ‘worst ant pest in the world’, discovered at Auckland International Airport. e Larvae and pupae cases of the disease-carrying Asian tiger mosquito found at wharves in Auckland and Wellington. e A yellow fever mosquito found in a container of used vehicles, also at an Auckland wharf. Since the discovery of the fourth black widow spider on Californian table grapes in November 2001, a six-month

importation ban has been imposed on the grapes. Forest and Bird welcomed the ban but believes it should have been imposed sooner. With imported used vehicles being the source of numerous border breaches last year, Karli Thomas says it is essential that offshore inspections be required. The Asian tiger mosquitoes were found in an imported used tyre and in a Japanese cargo ship. Fortunately, no mosquitoes were caught in traps set up in the area of either incident. The Asian tiger mosquito is a carrier of dengue fever, Japanese encephalitis and yellow fever. Figures from the Ministry of Agriculture and Fisheries show that the rate of gypsy moth interceptions on used imported vehicles tripled from 1998 to 1999. Gypsy moths are a serious pest that ‘could have catastrophic consequences for our native and plantation forests, Karli Thomas says. Forest and Bird is asking the Government to immediately review MAF’s Import Health Standard (IHS) for used vehicles. MAF proposed an improved standard in 2000, requiring the offshore inspection of all used vehicles,

but later abandoned it. Latest figures show that less than half of imported vehicles are inspected before being shipped here. Insect invaders also seem to be hitching plane rides. A single colony of ferocious fire ants that could have been up to two years old was found at Auckland’s International Airport. These aggressive ants have a sting similar to that of a bee or wasp, and if they took hold in New Zealand could make being outdoors extremely unpleasant. With an infestation of the ants now in Brisbane, incursions here have become more likely. Meanwhile, a $6 million nationwide programme has begun to contain the southern saltmarsh mosquito, first discovered in Napier in 1998. An ‘aggressive biter’, this mosquito is a carrier of the Ross River virus and represents a significant danger to the health of a range of animals, including humans. The southern saltmarsh mosquito has been found on the East Coast and in Hawkes Bay, but the largest infestation is in the Kaipara region, northwest of Auckland. Government policy is to eradicate the mosquito from the eastern sites, and to contain

it in Kaipara until the feasibility of eradication there has been investigated. Forest and Bird has asked for all of the infestations to be eradicated. Then, of course, there is the insect pest that has hit the headlines the most in recent times, the painted apple moth. An Australian native, the moth was first identified by a Forest and Bird executive member and entomologist, Dr Peter Maddison, in Glendene, a suburb of Auckland, in 1999. It has since spread to other Auckland suburbs. The painted apple moth poses a serious threat to our forests, horticulture and environment, although it spreads slowly as the female moth does not fly. This moth particularly likes to feed on wattle and acacia trees, but has also been found on ribbonwood and kowhai. The spraying of affected Auckland suburbs is expected to cost $11 million. The case of the painted apple moth emphasises the need for stronger biosecurity measures to prevent pest incursions happening in the first place, rather than having to resort to controversial and expensive measures after infestations occur.