Some visitors are more unwanted than others

The Verroa Destructor clings to the worker bee’s abdomen, sucking blood.

I get my share of pesky visitors and afflictions out here on the river but most of them don’t keep me awake at night.

There’s a low, sneaky fox who cruises past the back door every week or two and jerks me into profitless action; and there’s the big mobs of cockatoos and corellas that swing by, keen to prune the garden for the Missus.

Sometimes a possum will scramble through the lemons; summer brings the indian mynahs and the odd wriggly. Mostly, they are not enough to lift an eyelid.

The Boss, on the other hand, keeps his eye out for any uptick in rats tip-toe-ing across the roof and new paper wasp nests, as well as keeping the yard clear of hiding places for snakes – though it’s all pretty much part of his routine.

But this outbreak of Varroa Destructor in New South Wales has his sudden attention and he’s rummaging through his bee-keeping gear and reading up on what these nasty mites have done to bee-hives everywhere else in the world.

It’s not good news, he says – the Varroa mite breeds in the queen’s egg cells, deforming the bees and infecting the hive with other viruses; the adult female clings to the worker bees, sucking blood - eventually killing the hive. Many hives will be destroyed: millions of bees around Newcastle have been euthanised already.

The mite was detected in sentinel hives at the port of Newcastle a couple of weeks ago and, within days, Victoria and other states put a stop to any hives being moved interstate. Just as well, because on Tuesday they found Varroa infestations in hives at Narrabri, around 350 kms from Newcastle.

The mite couldn’t travel and be detectable that quickly, so it has clearly been in the state for some time – no-one knows how long – and has been carried by hives moved from one place to another, or by feral hives or perhaps even by queens bred in the Newcastle area and shipped elsewhere.

This is The Boss’s worry – it may have already snuck over state borders.

New South Wales quarantine officials were still hopeful this week they could eradicate and control the mite outbreak but The Boss is not confident. The mite arrived in Auckland in 2000 and they tried to protect the south of the north island but gave up in 2003; three years later it had jumped across Cook Straight into the south island and, after another two years, all restrictions to try and stop it moving further south were abandoned.

“That doesn’t mean we shouldn’t try, General,” he added hopefully.

Bee-keepers are being urged to start testing to see if there is evidence of the mite elsewhere and there are three different tests, two of them no fun for the bees. The alcohol wash involves half a cup of bees – about 300 - taking one for the team via a dunking in an alcohol solution with a vigorous shake, and draining the solution through a coarse sieve, so the tiny red mites – about 1.6mm wide – can be seen clearly.

Another method is scraping drone cells off the brood frames and examining them closely – with a magnifier for old blokes, The Boss says – a method also involving no future for the drone pupae scraped up.

The only bee-friendly method is the sugar-shake test, where the 300-odd bees are sprinkled with icing sugar and shaken vigorously, then tipped up so the icing sugar drops through a sieve, taking the mites with it. In this case, the bees emerge unscathed and a little sweeter, although the more brutal alcohol wash is regarded as the most effective test.

The Boss isn’t sure what it means for the huge annual effort to pollinate the almond crop in August – which could prove to be a massive mite-spreading event.

If the Varroa Mite conquers Australia too, the expensive miticides used to control it will need to be used very carefully to avoid honey contamination and it has taken bee-breeders overseas years to breed mite- resistant queen bees. Best to stop it…if we can. Woof!