News & NEWSLETTERS

Author: Megan Hughes, ABC Rural

Biosecurity Queensland is investigating how a parasitic mite related to the Varroa destructor mite, which has caused devastation in the bee and honey industry across New South Wales and Victoria, could have arrived at the Port of Brisbane.

A single individual of Varroa jacobsoni was found during a routine inspection of a sentinel hive at the port.

Like Varroa destructor, jacobsoni can cause colony losses.

A spokesperson for Biosecurity Queensland said tracing was underway to determine if the pest had spread beyond the port.

"Surveillance will be conducted in conjunction with the Queensland bee industry and the Australian government," they said.

Varroa jacobsoni has been detected in Queensland before.

It was first found in the Port of Townsville in 2016, but after years of work was declared eradicated in 2021.

This is the first new incursion since the National Management Group (NMG) for the varroa response shifted their focus from eradication to management as a Varroa mite plan was implemented.

Movement restrictions

While Varroa jacobsoni is a different species to the pest plaguing the southern states, it could become a significant threat to beekeepers.

Why are NSW's bees in lockdown?

Varroa mite could impact more than your honey toast. The parasite threatening bee populations agricultural industries rely on.

While the mite's natural host is the Asian honeybee (Apis cerana), researchers from the CSIRO have observed it reproducing on European honeybees (Apis mellifera) — the species favoured in commercial honey production — in Papua New Guinea.

Biosecurity Queensland is expected to issue movement restrictions for hives in the detection area to prevent further spread.

"The movement restrictions will apply to all beekeepers who have hives in or have had hives in the surrounding localities to the Port of Brisbane within the last 90 days," the Biosecurity Queensland spokesperson said.

Restrictions will include the movement of bees, bee hives, and bee products including honey and used beekeeping equipment.

Beekeepers must also notify Biosecurity Queensland of any hive movements in or out of the movement control area or any bees bought or sold in the past 90 days.

Author: Clarence Slocklee Gardening Australia, ABC

Blue is a rare colour in nature, but there are some spectacular blue Aussie flowers that add interest to any garden; Clarence suggests a few.

Blue wildflowers in the bush really stand out – partly because humans have an affinity to blue but also because blue is one of nature’s rarest colours – only 10% of flowering plants have blue flowers and almost none have blue leaves.

Blue is a hard colour to produce. To look blue, plants use red pigments, called anthocyanins, whose appearance is changed by acidity levels to appear red, purple or blue. That’s how you can alter the colour of a hydrangea flower from red to blue by changing the acidity of the soil.

So why bother? Because bees are drawn to blue flowers, so being blue increases a flower’s chance of being pollinated.

Scaevolas or Fan Flowers

Fantastic performers, blooming from spring to autumn, spilling over pots and hanging baskets, or growing as a groundcover in gardens. They don’t need deadheading, they attract bees and butterflies, and have few pests and diseases. They like a sunny spot and good drainage, but can handle dry conditions, light frosts or sea winds. Up to 15-20cm high, they can form wide mats, so give them some space.

Lechenaultias

Famous for their jewel-like, intense colours, and the blue form - Lechenaultia biloba – is a standout. Native to WA, they need a sunny spot with excellent drainage so are best in a container if you’re not on sand. They form a mound to 30cm tall and 30-50cm wide and can be short lived, but are relatively easy to propagate, so try taking cuttings to replace your plant.

Isotoma

Found in well-drained granitic soils across the Eastern states, Isotoma axillaris is tougher than its delicate look suggests. They like full sun and will reward with long-lasting flowers from spring through to autumn.

Dampiera

In the same family as Lechenaultia [Goodeniaceae], dampieras come in a range of colours and forms but most have blue flowers. Dampiera trigona forms a loose mound to 30cm high and is great in containers, or where it can mingle with other plants, forming superb colour combinations. They like sun or light shade, well-drained soil and a warm spot. The bees and butterflies love them.

Dianellas

The strappy flax-lilies nearly all have blue flowers, and many are followed by blue berries, so you get a double dose of blue. ‘Lucia’ is a cultivar of Dianella caerula, which comes from the Latin for ‘dark blue’ so that’s a giveaway about its colour. Growing 30-40cm high and spreading to clumps about 50cm wide, they’re great for nature strips, borders or tough spots because they take sun or part shade and tolerate dry and frost, sand to clay.

Blue was preserved for royalty and gods, but with these plants you can enjoy some heavenly blue in your garden every day.

Original article and video can be found here.

Canoelands orchard farmer John Christie was fearing the worst. In 2022 the deadly bee parasite varroa mite had penetrated Australia’s borders at Newcastle on the NSW central coast. Just months later, in July 2023 at Canoelands, Christie’s beloved bees had been doused in petrol and killed by government officials – without even testing for the presence of the mite. It was part of a rash NSW government eradication program, to eliminate the deadly mite from Australia, something no other country had ever achieved once it had arrived.

As the mite spread across NSW, tens of millions of bees were destroyed and businesses were lost until eventually, the government conceded the plan was a failure. In Australia, as in every other country infested with the mite, it became abundantly clear the mite needed to be managed.

Like so many other farmers, Christie credited the success of his beautiful 100 year old family farm at Canoelands to the presence of his bees – with ten beehives, diligently pollinating until the end of each spring each year. But as the government and industry bodies steadfastly stuck to the eradication strategy, pleas for an alternate strategy by Christie and other farmers and beekeepers to manage the infestation fell on deaf ears.

For generations, Christie’s Canoelands Orchards has been a cornerstone of the Hawkesbury region, supplying Sydney with fresh stone fruit, citrus fruit, apples and berries. With encroaching development, many city fringe farmers haven’t survived. Christie’s family farm is one of the last in the north west rim.

Part of the key to the success of his operation has been the presence of his beehives. However, on that Monday night in July, the Department of Primary Industries (DPI) left Christie devastated. His daughter-in-law Christie told the Hawkesbury Post at the time “Our bees are being killed. Our hearts are broken!! There is no sign of the mite in our hives. ….Although we understand the threat and the requirement for drastic action, if more was done to ensure that this didn’t spread in the first place we would not be in this position. This is just so sad,” she said.

Spring has now come and almost gone. It’s been an unusual season Christie says. The high temperatures and dry early season. “It’s been a very different season. It’s been a very early fruit picking season. Fruit that we would not have picked until next year we are picking now,” he says.

All up he reckons the crop is 30 %down. Whether that is the reduction in bees or seasonal conditions, most likely a mix of both – it’s hard to tell. The outcome has been better than he expected. “There were quite a lot of bees they didn’t kill. They killed all the bees from people that were registered and that had hives, but not all the hives were registered, and there were quite a lot, they didn’t bait the stations.

“There are bees around, we know there are bees around, it’s surprising,” Christie said.

For a man who has given his life to his orchard and bees, the experience has been bruising. With a weariness in his voice Christie is however still looking to the future.

“I pretty much haven’t got over it yet. I haven’t got any more bees back. I’ll get myself into gear one day but right now I’m cracking on. I’ve lost a bit of heart over it. So I think I’ve got to toughen up and go and get some more bees,” he said.

“As far as the future goes, yeah, I don’t know. There are a lot of other pollinators out there aside from bees. It’s not the end all, here.”

The Department of Primary Industries and Regions together with the Beekeepers' Society of South Australia (BSSA) and the South Australian Apiarist Association (SAAA) are holding a varroa mite information session covering:

• National Varroa Response Transition to Management plan
• Management of varroa mite using IPM principles
• Discussion around South Australia's preparations regarding varroa mite.

The meeting will be held on Sunday the 26th of November from 3pm to 5.30pm at the Bridgeport Hotel in Murray Bride. You can register to attend in person or online session for free at eventbrite.com. 

Article taken from the ABC

Reports of bee swarms in South Australia's South East have increased significantly after a "hectic" spring, but the ongoing threat of varroa mite to feral bee populations has potential to near-eradicate swarms in coming years.

Pest controller and apiarist Sam Shaw said demand for swarmed bee removals has increased about tenfold from two or three calls per month a few years ago to 20 or 24 per month this year.

"So far it's been pretty hectic," he said.

"We've had a good spring so far. I know [the swarming season] came a bit later last year.

"It just completely depends on the weather as well and it depends on how much room the queen has in a hive."

Swarming creates new colonies

Australian National University evolutionary biology professor Sasha Mikheyev said swarming was how honey bees reproduced.

Professor Mikheyev said significant rainfall over the past three years had led to increased food for bees.

"When conditions are good, the honey bees raise plenty of young. They have many new individuals and lots of food," he said.

"That's when they decide that they can split and both halves of the original colony will keep growing. The mission is reproduction.

"They've had opportunities over the past few years to build up their honey stores and also to build up their worker numbers.

"What we're seeing now could be a manifestation of that."

Although swarms more often form due to favourable conditions for bees, Professor Mikheyev said bees would also abandon a hive if it were diseased.

In areas infected by varroa mite, this could lead to an increase in swarming behaviour.

"If a colony is very heavily infested, they will sometimes fly off," Professor Mikheyev said.

"Varroa tends to be around the brood and only a small fraction of them will go onto the honey bees and be transported, so swarming is a short-term solution for honey bees to deal with varroa."

But in the long-term, scientists say the impact of varroa on feral European honey bees could reduce swarm frequency.

"The swarms that we see now, we might not see quite as many of them a few years from now," Professor Mikheyev said.

Domesticating swarms

Mr Shaw said one benefit of beekeepers domesticating swarmed colonies was that it allowed for captured feral bee populations to be supervised more closely for varroa and other diseases.

"We leave them for a week or so just to calm down and for them to get a bit settled, and then we'll do frequent inspections on them, usually weekly but maybe every fortnightly," he said.

"We have to do yearly testing for varroa mite and any other hive diseases."

Professor Mikheyev said national regulation for stricter management of supervised colonies, kept by both commercial and hobby beekeepers, would soon be enforceable.

"They'll receive some sort of chemical treatment that will help keep the mites in check, otherwise the colonies will die," he said.

"The feral bees of course will get no such treatment and it's not clear how many of them will die, but it's very likely to be more than 95 per cent."

While swarms were typically timid, Mr Shaw advised people to stay away if they came across one.

"It completely just depends on if they're aggressive or not," he said.

"You'll find out pretty quick if you're walking past and they are aggressive.

"Most of the time a swarm can just be resting there for a brief moment and they could be gone within a couple of hours." 

Original news article can be found here.

James Cook University scientists say a common tropical bee species is vulnerable to widely-used insecticides – which will decrease their heat tolerance at the same time as the climate is warming.

JCU PhD candidate Holly Farnan led the study, published today in the journal Royal Society Open Science. She said bees are critical components of natural and agricultural ecosystems and concern is growing about declines in their populations.

"These declines are likely driven by a myriad of stressors including habitat loss, pathogens and parasites, competition from introduced species, poor nutrition and insecticide exposure," said Ms Farnan.

She said the research focused on Tetragonula hockingsi, a small stingless bee that lives in the tropics and subtropics of Queensland and the Northern Territory and is a pollinator of both native plants and crops including mangos and lychees.

The scientists tested the bees' response to common insecticides and heat stress.

"Effects of insecticides could be reduced if bees avoided foraging on flowers contaminated with insecticides. But our work revealed no consistent avoidance of the insecticides by the bees.

"We also found the bees had diminished tolerance of heat stress after non-lethal exposure to the insecticides," said Ms Farnan.

"Even bees exposed to miniscule amounts of insecticide, certainly not enough to kill them, were more susceptible to the effects of heat."

She said climate projections suggest global warming of less than 1°C will cause tropical regions to experience extreme conditions sooner than other regions of the globe.

"The combination of heat stress and insecticide exposure may put this stingless bee at increased risk of decline," said Ms Farnan.

See original article here

Scientists uncovered how honeybees organise their collective defence in response to predators and used computational modelling developed at the University of Innsbruck to identify potential evolutionary drivers of the behaviour.

When a honeybee colony is attacked by a predator or seriously disturbed by a human who - accidentally or intentionally - got too close to the hive, the bees of the colony launch a coordinated counterattack to defend the colony and to scare off the trespasser. An important stimulus for them to start chasing and stinging the intruder is the presence of an alarm pheromone, which the bees carry on their stinger. In the event of an attack, the pheromone is dispersed either actively - by guard bees - or automatically upon stinging - by recruited soldiers. Thus, it carries information not only about the presence of an attacker, but also about the extent of the colony's counterattack. "The more bees have stung the intruder, the more alarm pheromone has been released with each sting and the higher its local concentration," clarifies Dr Morgane Nouvian, a biologist from Konstanz and joint-lead author of the study together with Andrea López-Incera from the University of Innsbruck.

To understand how individual bees from the hive may use this information to make the ultimate decision to sting and possibly die for the good of the colony, the scientists observed individual stinging responses of Western Honeybees (Apis mellifera) from three colonies. Using different concentrations of natural and synthetic alarm pheromones and a dummy predator, they revealed that the aggressiveness towards the dummy - measured as the stinging likelihood - initially increases with the concentration of the alarm pheromones until it reaches a peak. However, at high concentrations, the aggressiveness drops back to a low level. This is the first time decreasing aggressiveness at high pheromone concentrations has been demonstrated under controlled experimental conditions. "One possible function of this 'stopping' effect of high concentrations of the alarm pheromone could be to avoid over-stinging and unnecessary sacrifice when attacking an already defeated intruder," Nouvian suggests.

Artificial intelligence reveals evolutionary processes

In social insects, be they honeybees or other social species such as army ants, individuals often coordinate their actions for the benefit and survival of the colony. For this reason, evolutionary selection processes in these insects acts on the group rather than the individual level. "Normally, if an organism dies, it cannot pass on its genes to the next generation anymore. In a bee colony, however, it is the queen that is responsible for reproduction. If another bee dies defending the hive but saves the queen in the process, the colony will continue to reproduce," Nouvian exemplifies. Because the bee colony functions as a single 'superorganism,' the behaviours of the belonging individuals can only be understood through the collective outcome to which they contribute.

To further analyse their experimental results and address this peculiarity of the evolution of collective behaviours, the scientists used computational modelling based on so-called Projective Simulation, an approach originally developed by co-author quantum physicist Hans Briegel and his colleagues at the University of Innsbruck. In their agent-based model, each agent or "bee" has a very limited set of percepts - the concentration of the alarm pheromone and a signal that the predator is leaving - and actions - to sting or not to sting - relevant to the defence behaviour. "Based on this approach we have developed a model that is realistic but not too complex," explains Andrea López-Incera from the team of Hans Briegel: "In our computer simulation, each agent was called in turn to perceive the current level of the alarm pheromone. When a 'bee' stings, the concentration of the pheromone increases and the decision of the next 'bee' is based on a new pheromone level."

A second important aspect of the model is that it includes a learning component: Neither the responses of individual bees nor the rules of interaction between them are predetermined. Instead, they "evolve" over many cycles of the simulation or, in other words, over many generations of the collective. "If decisions made by individual agents are beneficial to the collective under certain environmental pressures, they are positively reinforced. This increases the likelihood that the next generation will act similarly under identical conditions", Andrea López-Incera clarifies. Taken together, the agent-based approach with reinforcement learning at the group-level allowed modelling of the observed defensive behaviour of honeybees from the perspective of both, the individual bees and the collective.

Putting the model to the test

Using the model and different parameter combinations, several predictions could be made about the possible influence of environmental pressures on the defensive behaviour of bees. For example, the simulations suggest that colonies adapt to the strongest predator they encounter. This means that colonies that primarily encounter weak predators, such as mice or toads, are less likely to sting at high pheromone concentrations than colonies that more frequently encounter strong and difficult-to-deter predators, such as bears. "For the survival of the colony, it makes perfect sense to be able to cope with the worst predator around, even if that means over-stinging some of the weaker predators," Nouvian describes.

The scientists also applied their model to the case of the notoriously aggressive "African bee", a subspecies of the Western honeybee. It has previously been suggested that the highly aggressive behaviour of this subspecies evolved in response to higher predation rates in the tropics and to highly specialized, hard-to-deter predators, such as honey badgers. Indeed, the simulation predicted that bee populations suffering from a high predation rate and predators that take a high number of stings before stopping their attack - as a model for the African bee - develop stronger defence responses than those that do not.

"We were quite happy to see that our model supports the current hypotheses on how the higher aggressiveness of 'African bees' might have evolved. One of the next steps will be to collect empirical data from real bees in Africa to verify the results," Nouvian gives an outlook. Another step for the future is to model a more diverse population of bees. As mentioned before, there are at least two different types of bees involved in the defence attack of a real hive: guards and recruits. "In the current model, each bee in the collective followed the same decision-making process. Training a model with two different types of agents and comparing it with experimental data will be very interesting," Müller adds. In general, the modelling approach is highly versatile and can be applied to other tasks and species, providing a valuable new tool for studying the evolution of collective behaviour.

The research was financially supported by the Austrian Science Fund FWF and the Volkswagen Foundation, among others.