Varroa Mites have made their way to Australia. It was to be expected given that we are surrounded by countries that have them. Fortunately, it occurred in Northern Queensland and it was Varroa jacobsoni that look for Asian Honey Bees (AHB) as a host. It is the Varroa destructor mite that preys on European Honey Bees. However, it should be noted that there are reported cases of Varroa jacobsoni on European Honey Bees.
The first detection of Varroa Mite occurred at the port of Townsville in June 2016. Five mites were discovered in a nest of AHB in a container stand at the port. The incursion occurred just before the almond pollination season was to commence, but the initial review indicated that it was likely to be isolated to the Townsville area and a ten kilometre zone was put in place under the Movement Control Order.
The ABA, as a signatory to the Plant Health Australia Emergency Plant and Pest Response Deed (EPPRD) and as an affected party, was part of the working group developing the response plan. This group is bound by confidentiality, particularly in the first few days as efforts to quarantine the initial 10 kilometre zones were established as it was important that hives were not moved until the Movement Control Order was put in place.
One of the key information points considered was that there were no commercial beekeepers operating in the Townsville region which limited the likelihood of the Varroa jacobsoni crossing to European Honey Bees and being spread as a result of normal hive movement before the incursion was detected.
The response plan developed to eradicate the Varroa Mite, at an estimated cost of $2.6 million, has focussed on finding and eliminating AHB hives in the region. So far there have been 10 feral hives discovered and dealt with. These subsequent discoveries of AHB hives in other areas of Townsville has seen the zone expanded.
On 17 July, a single Varroa jacobsoni was found in an AHB nest on a property in Annandale. This property is about nine kilometres south west of the Townsville port.
The tenth detection of Asian Honey Bee occurred on Friday, 11 November. National Varroa Mite Eradication Program staff conducting surveillance for Asian honey bee detected and destroyed a suspect feral nest at Queens Park located three kilometres west of the initial detection at the Port. Most of the nest was sampled and no varroa mites were detected on the bees or the comb. Genetic analysis results indicate that all the AHB tested from the first nine feral AHB detections are related to each other, suggesting they all originated from the same incursion.
Biosecurity Queensland is continuing its surveillance activities that involve sweep netting flowering plants, setting feeding stations to attract any foraging bees, analysis of rainbow bee-eater pellets collected from known roosting sites, and aerial pheromone traps to detect male Asian honey bees.
Catch boxes and sentinel hives that are set permanently around the Townsville port continue to be checked.
The Movement Control Order remains in place, which restricts the movement of bees, bee hives, bee products, and used bee keeping equipment from the zone.
To date the incursion is showing signs of containment and successful eradication.
On other biosecurity matters, the Khapra Beetle incursion in South Australia appears to have been successfully dealt with. Eradication appears the likely result although monitoring is ongoing.
The ABA was advised on 21 November, that American Plum Line Pattern Virus (APLPV) had been detected in one apricot sample from Queensland and two plum samples from Victoria. The virus is likely to have been present for some time as it was detected in old trees growing in Mildura, Melbourne and Brisbane. The symptoms associated with APLPV can be confused with other viruses occurring in prunus in Australia. The virus is transmitted via vegetative propagation or grafting of infected material. Spread via other means such as vector, pollen or seed is not known. The case for using virus tested budwood in producing almond nursery trees is further strengthened.