In early December New Zealand Beeswax general manager Nick Taylor hit the road in Australia to educate their beekeepers on varroa treatments, with efforts to eradicate the mite having been halted and attentions turned to management. Having covered more than 2000 kilometres in a rental car in a week to make six meetings between Armidale in northern NSW to Canberra, ACT, with between 40 and 100 beekeepers at each venue, Taylor reports back here.
By Nick Taylor
I Opened each meeting with a 15 minute gambit covering key messages, followed by interactive questions from the floor. Between the meeting, the bar and a meal after, typically 100 questions came flying in, 98% of which were the same from meeting to meeting.
Overall, I was very impressed with the thoughtful and considered questions from the floor. Many had clearly been doing their research and, most impressively, they were taking ‘guru’ advice from Youtube and forums, with a healthy dose of scepticism. Arguably I was preaching to the converted, that being the proactive first movers, open to build their knowledge base ASAP.
It felt necessary to start each meeting with an apology – varroa is not a fun topic and I felt like the grim reaper standing at the front of the room with my scythe. It was important to relay that varroa isn’t a death knell for their industry, varroa and the associated viruses are just one more management challenge to overcome (of many!). There is no one definitive source of all varroa knowledge, no one size fits all, just accumulated skills and experience and taking any/all advice with a grain of salt (including mine).
Key messages I tried to impart were:
Varroa control requires a 12 month strategy; select multiple best in class treatments, e.g. Amidine (Apivar), Pyrethroid (Bayvarol) and at least one organic (Formic Pro, oxalic acid). Alternate and always use full dose for full treatment period, and monitor, monitor, monitor. Timing comes down to slotting these 10 week, eight week, one week treatment windows into the individual beekeeper’s unique business calendar and climate.
When monitoring, it’s important to be consistent with methodology/technique, to ensure a consistent and comparable number. Best practise world-wide is to take a 300 bee sample (1/2 a cup) from the brood chamber (after first ensuring the queen is safe), then use a fit for purpose device with alcohol or CO2 (non-lethal) for the most accurate results. The resulting number of ‘mites in a wash’ is a data point most beekeepers use globally. The scientific community will often use a percentage instead, simply take the ‘mites in a wash’ number (assuming ½ a cup i.e. 300 bees) and divide by three e.g. three mites in a wash is 1%, six mites in a wash is 2% etc. Make sure you are speaking the same language. Current guidance from the NSW Department of Primary Industries is to monitoring every 16 weeks and when one hive in an apiary reaches six or more mites in a wash, then treat the whole apiary.
The honeymoon phase with varroa will initially leave generous room for trial and error because the compounding negative consequences of high virus loading can take months/years to irreversibly peak. The beekeeper’s early intervention will help prolong this phase, minimising the damage to their hive. However, the decision making of their neighbours and/or proximity to feral bees, may result in the need to perpetually treat until the feral colonies/neighbours disappear.
With up to 150 hives per square kilometre, Australia has among the highest feral honey bee densities in the world. There are recent anecdotes of managed hives being reintroduced in the original red zones around Newcastle only to be infested with mites within days, and off the chart mite loading within weeks. This intense pressure from feral bees will be an ever-present risk that could drag on for years.
There are three key differences with commercial beekeeping in Australia and New Zealand, speaking in sweeping generalisations:
the Aussies feed their bees with diesel, i.e they are almost continuously moving from one floral source or pollination event to the next, typically for nine to 12 months of the year, with no two years exactly the same. Most Beekeepers in the room would cover more kms in a single day, than most Kiwi hives will cover in a whole year.
With the exception of a few inland/higher elevation spots and the furthest south, bees don’t have a winter broodless period. For the week I was there, daytime highs were between 37 and 42°c!
They can go months without looking in the brood chamber. In their new varroa world, this will need to change. Staffing/loading numbers will need to be adjusted to meet the new workflow (treatments in and out, health checks, requeening more often, monitoring, firing up hives for early spring crops/pollination etc).
All of the above results in a much longer season, greater variability year to year, and no winter brood break to pause the insatiable march of varroa. The typical Kiwi strategy of a calendar core Spring and Autumn treatment rotation, supplemented with an (or multiple) organic flash treatment(s) to help supress growth in-between, leaves our Aussie compatriots scratching their heads. The mental gymnastics required to fit this into their 12-month carnival tour of the state is a bridge too far at this time as they understandably are not wanting to take on unnecessary costs and/or forgoing a revenue stream from honey/pollination.
The varroa wave is coming to them and the choice ahead is binary: get on the front foot, take control of what you can control through proactive best in class strategies (outlined above), or, alternatively, take the reactive route, and continuously be chasing your tail.