News

By Darren Bainbridge

With the recent outbreak of varroa in Australia, attention turns to what New Zealand is doing regarding our ongoing battle with varroa and detection of new biosecurity incursions.

Darren Bainbridge wonders, is it time we up our game on biosecurity?

While some may argue that – with the presence of varroa – the worst of the unwanted exotic pests and diseases are already here. However, I’m pretty sure any discovery of tropilaelaps mites or tracheal mites, and their associated viral loading, would see many hives burned and have a significate negative impact.

With reports of pockets of varroa resistance to amitraz and flumethrin needing further investigation, is it time we up our game? Is greater education needed on the consequence of under treating and how to conduct effective surveillance with mite washes? Is it time for a national database for recording treatment, mite washes and sightings of possible exotic disease/pest?

The short-term financial gain of taking a shortcut seems to still win out with some, especially when cashflow is tight. On a recent trip to visit beekeepers I witnessed the reusing of gib oxalic-acid staples to try and save further on an already ridiculously cheap treatment. My mind goes straight to the possible consequences of disease spread, let alone the reduced effectiveness of already soaked (wet) staples. Will they be able to detect ineffectiveness early enough to recover? I guess time will tell.

Areas in which varroa has recently been found in New South Wales.

A bit of desktop research reveals we have a fairly robust system for the detection of any new pest, with the surveillance programme run by AsureQuality on behalf of the Ministry for Primary Industries (MPI). It monitors 350 apiaries in 19 geographic areas throughout New Zealand classified as high-risk, 12 in the North Island and seven in the South Island. Further to that, bee exporters are also required to submit samples for testing, while the Bee Pathogen Programme (run by Hayley Pragert and Richard Hall from MPI over a two-and-a-half-year period 2016-18 and inspecting more than 2500 hives) did not detect any new incursions.

However, with most surveillance samples taken only annually (by the looks of MPI’s public information), I do question New Zealand’s ability to gain an early detection. We are learning from Australia, that early detection makes possible effective quarantine and eradication of an incursion before it can take hold.

History would show our surveillance systems to be lacking, with varroa destructor’s spread in 2000 and nosema ceranae being found in Coromandel in 2010, outside of a “high-risk” surveillance area.

Australia has a National Sentinel Hive Program, now with 178 sentinel hive/catch boxes across 33 sea and air ports. These hives are visually inspected every six weeks for large African hive beetle, braula fly and small hive beetle. Acaricides (miticides) are used to check for external mites and samples of adult bees are taken to labs for diagnosis of internal mites and viruses.

Several detections and resulting successful eradications of Asian honey bee (Apis cerana), with varroa mites present, indicates the programme to be working.

However, the recent outbreak of varroa mites detected on European Honey bees (Apis mellifera) in Newport, New South Wales, has been a wakeup call and scary for many Australian beekeepers. Its detection in late June was initially thought to be relatively swift, with early reports the mites may have entered as late as April/May 2022. However, talk is now turning to the belief that varroa might have been in Australia for up to a year and entered the country outside of the surveillance zone, before being identified in a sentinel hive. If they are to have any hope of eradication, they will be much better placed if the invasion has only lasted three months so far, not 12, thus providing less opportunity for spread.

More sentinel hives checked more often is the ideal – early detection is the best prevention.

Darren Bainbridge is the founder and general manager of MyApiary, a provider of beehive, apiary and honey house management software, as well as beekeeping business advisory and consultancy. www.myapiary.com

See the original article at: https://www.apiaristsadvocate.com/post/biosecurity-matters-just-ask-oz.