Latest developments on colony collapse disorder:
Beekeepers want precautions against Australian bee virus
Suspicions that a virus found in Australian bees is triggering the widespread collapse of bee colonies in the United States may have serious implications for New Zealand, a senior scientist says.
"Because it's a pathogen, it means we are at risk of getting it here," said Hortresearch honey bee scientist Mark Goodwin.
And NZ beekeepers plan to ask biosecurity officials to block imports of Australian honey until the extent to which the virus has spread in Australia has been scientifically surveyed.
American researchers have used DNA sequencing on a huge scale and statistical analysis to identify Israeli acute paralysis virus (IAPV) as the common link to widespread deaths of worker bees, or a "marker" for the phenomenon.
"We can use it as a marker and we can use it to investigate whether it does in fact cause disease," said Dr Ian Lipkin, a Columbia University epidemiologist who headed the study with Diana Cox-Foster, an entomologist from Penn State University.
The online edition of the journal Science yesterday published the study, which said that the virus may be combining with the effects of parasitic varroa mites - which can spread the virus - pesticides, poor nutrition, and the stress of being shuttled around the USA to pollinate crops.
A Verroa mite is visible here on the back of this bee
About 25 per cent of America's beekeepers have reported colony collapse disorder has killed between 50 per cent and 90 per cent of their hives. The discovery that sterilising diseased hives with radiation killed the mystery infectious agent focused early attention on viruses, bacteria and fungi.
The researchers found IAPV in Australian bees, and they are now planning to go back through historical US samples to see if those imports - which began in 2004 - really were the first carriers. If they were, the US might consider closing its borders to Australian bees.
Dr Goodwin said the research raised the possibility that IAPV will be one more disease-causing organism New Zealand must try to keep at bay. "It's very suggestive that this is the cause - the next thing the American researchers have to do is to try to deliberately infect bee colonies with the virus and get the same effect," said Dr Goodwin.
National Beekeepers Association executive officer Jim Edwards told NZPA that his group would be asking biosecurity officials at the Ministry of Agriculture and Forestry (MAF) to take precautions against accidental import of the virus.
MAF began allowing imports of Australian honey late last year - including honey from Western Australia which had not undergone heat treatment - but temporarily stopped them while beekeepers fought a court case over the issue.
Before they were aware of that IAPV in Australia might be a factor in colony collapse, the NBA argued that MAF did not have the power to permit entry of "passenger" micro-organisms it knew would be in the honey. The case has been taken to the Appeal Court by the beekeepers.
Mr Edwards said beekeepers were already concerned about a new virus in their part of the world, but the possibility that it was triggering colony collapse in bees already affected by varroa called for early intervention by MAF.
"If it's present in Australian bees, then there is a need to define in parts of Australia it is found and the extent to which it is a risk for New Zealand, where bees are already weakened by varroa," he said.
Proof of Australian bees having triggered the colony collapse was unlikely to boost demand for NZ bees in the United States. The almond orchards in California which imported a lot of Australian bees flowered too early to suit bee imports from New Zealand. Also, if the virus was present in on both sides of the Pacific, the US would have nothing to lose by continuing imports.
A senior policy analyst at MAF Biosecurity, Paul Bolger, said NZ did not import live bees or bee semen from Australia, which were the most likely way bee viruses might be spread.
"The report in Science has only just been published and we are still assessing it to determine the appropriate steps to take," he said. MAF was not aware of any evidence that IAPV was in New Zealand, and there had been not reports of symptoms of colony collapse disorder.