A live female black widow spider was found in a bunch of Californian table grapes in a Nelson supermarket earlier this
Justin Downs MAF’s National Advisor, International Operations (Plant Imports) says MAF is taking this latest find very
“We are currently working with the United States Department of Agriculture (USDA) to clarify whether this finding is the
result of a systems failure or not.
“Clearly if Import Health Standards protocols have not been followed we will need to close the trade in Californian
table grapes” he says.
Mr Downs says a meeting with other government biosecurity agencies will take place early next week to discuss options
and determine the best course of action in view of the latest finding.
In the meantime imports from the treatment facility in California will be suspended until the USDA completes its
This is the fourth finding of a black widow spider in Californian table grapes this year.
The first two finds were the result of a fumigation failure and resulted in a suspension of imports of California table
grapes while the treatment facility was being investigated.
Following the third detection a major audit was undertaken and no fault could be found in the procedures followed by the
New Zealand imports approximately 400,000 cartons of Californian table grapes a year.
“While unfortunately we may find one black widow spider per million bunches of grapes, our Import Health Standards are
fully effective in ensuring the glass-winged sharp shooter does not enter New Zealand.”
Chief Advisor Safety and Regulation, Dr Bob Boyd said other black widow spiders may have arrived in New Zealand
undetected, and retailers and consumers should remain vigilant.
“Although the black widow spider is not normally aggressive, it will bite to defend itself or its eggs. The spider's
bite is venomous. The effect of a bite may result in abdominal pain, breathing difficulties, nausea and vomiting. Full
recovery can take up to 10 days,” he says.
Dr Boyd said it was highly unlikely that a healthy person would die as a result of a black widow spider bite, however
very young, very elderly or debilitated people were at greater risk.
The male spider has an elongated black shiny body, with white and red markings on its side. The female's abdomen is
almost spherical, usually with a red hourglass mark on its back or two red marks on its back. It may grow up to the size
of about a 20-cent coin.
Dr Boyd said there is a native New Zealand spider that has a similar appearance, but the distinctive feature about the
black widow was the markings on its back.
If anyone finds what may be a black widow spider, they should approach with caution. People should avoid physical
contact. Fly spray could be used to stun the spider to allow it to be killed and/or placed into a sealed jar.
Dr Boyd said anyone who suspects they may have been bitten by a black widow spider should place ice on the bite, and
seek urgent medical attention. The injury is treated symptomatically. If the spider can be captured without endangering
anybody, it should be caught to confirm its identification and the local public health service advised.
For further information contact: Philippa White MAF Biosecurity Communications 04 4989968 or 025 223 1875