On Thursday 20 October 2016, the House of Representatives Standing Committee on Agriculture and Water Resources resolved to conduct an inquiry into a matter arising from the 2014-15 annual report of the Department of Agriculture, namely the biosecurity of the Australian honey bee industry.
The Committee held a roundtable discussion on honey bees and biosecurity on 24 November 2016. The roundtable was attended by the Department of Agriculture and Water Resources (DAWR), CSIRO, the Australian Honey Bee Industry Council (AHBIC), and Plant Health Australia (PHA).
The Committee approached the roundtable as an opportunity to better understand the biosecurity threats the beekeeping industry faces and assess the adequacy of Government risk mitigation strategies. This report will summarise the evidence received at the roundtable and will outline the conclusions the Committee has reached based on that evidence.
There are a variety of bee species, both native and imported, that live in Australia. Amongst them are:
the European honey bee (Apis mellifera, referred to throughout as the honey bee), an imported species that has spread throughout Australia and is present both in the wild and in hives managed by beekeepers (the honey bee is the main focus of this report);
the Asian honey bee (Apis cerana) which is native to south-east and mainland Asia, and which has recently become established in northern Queensland;
diverse species of native bees, which are found throughout Australia; and
bumble bees (Bombus terrestris), which are present only in Tasmania.
Honey bees in Australia may be referred to as ‘managed’, which means they live in hives kept by bee keepers. They may also be called ‘wild’ or ‘feral’, which means they live in the environment without human intervention. According to the CSIRO, Australia’s population of feral honey bees is amongst the highest in the world due to the prevalence of high-pollen tree species like eucalypts and proteas.
Role and value of honey bees
The economic value of honey and other hive products produced by managed honey bees in Australia is comparatively small at an estimated $100 million per year.
However, honey bees make an enormous indirect contribution to Australia’s economy through the pollination services they provide. Pollination of crops and plants involves the fertilisation of flowering plants via the transfer of pollen between them. Many fruit, nut, vegetable, legume and seed crops cannot bear fruit or seeds without being pollinated. Although a range of insect species can pollinate plants, honey bees play a vital role in pollinating many horticultural crops.
In addition to pollinating crops, honey bees can also assist the grazing industry by improving the yield and persistence of common fodder crops such as clovers. This can reduce agricultural input costs and may also have environmental benefits by reducing graziers’ need to use fertilisers or other chemicals.
Though their value to Australia’s economy is difficult to quantify, AHBIC estimates that pollination services provide approximately $4 billion per annum in value to the agricultural industry. In 2014 the Senate’s Rural and Regional Affairs References Committee’s honey bee report noted estimates of $1-4 billion per annum in value. Honey bees therefore provide substantial value to Australia’s agricultural industry and the Australian economy more generally.
The honey bee industry and biosecurity
At the roundtable, representatives from AHBIC painted a mostly optimistic picture of the honey bee industry but also drew the Committee’s attention to a range of biosecurity threats which could have a severe impact on honey bees and the pollination services they provide in the near future.
Australia has been historically fortunate in that its physical isolation has enabled it to remain free of many of the worst plant and animal pests and diseases. However, the risk of invasive pests or diseases arriving here has become more acute due to growing trade links with the rest of the world and increasing international travel.
The Australian honey bee industry is not immune to these risks and faces a range of biosecurity threats. These include invasive bee species such as the Asian honey bee, which has become established in northern Queensland in recent years, and a range of bee pests. However, the discussion of biosecurity threats at the roundtable overwhelmingly focused on the threat posed by the Varroa mite.
The Varroa mite
Varroa mites are small parasites that feed on the haemolymph (a fluid equivalent to blood) of larval and adult bees. There are two primary species of Varroa: V. destructor and V. jacobsoni. Most strains of V. jacobsoni can only target the Asian honey bee and it is therefore regarded as less of a threat to the Australian honey bee industry. V. destructor, which can affect honey bees, has spread to every beekeeping country in the world except Australia. On its website, DAWR describes Varroa as follows:
[The] Varroa mite, Varroa destructor, is a small mite, around 1 mm in diameter, that parasitises species of bees in the genus Apis, such as Apis cerana, the Asian honey bee, and Apis mellifera, the species that includes the European honey bee. In the 20th century two strains of V. destructor moved hosts from the natural host, the Asian honey bee, to the European honey bee. The K strain of Varroa destructor (K stands for Korea, the country in which the strain is thought to have originated) has spread world-wide and is regarded as the major challenge facing beekeeping internationally.
Varroa infestation can have catastrophic consequences on honey bee colonies. While bee hives with low numbers of Varroa mites can continue to function normally, mite numbers will tend to rise over time and cause a range of increasingly serious problems, culminating in the collapse of the hive:
Heavy Varroa mite infestations can build up in 3–4 years and cause scattered brood, crippled and crawling honey bees, impaired flight performance, a lower rate of return to the colony after foraging, a reduced lifespan and a significantly reduced weight of worker bees. Colony symptoms, commonly called parasitic mite syndrome, include an abnormal brood pattern, sunken and chewed cappings and larvae slumped in the bottom or side of the cell. This ultimately causes a reduction in the honey bee population, supersedure of queen bees and eventual colony breakdown and death.
A V. destructor incursion in Australia is regarded as a serious threat to both the beekeeping and horticulture industries. It would most likely decimate Australia’s feral bee population while making it significantly more difficult to operate managed hives. This could have a substantial disruptive effect on Australia’s horticulture industry. Australia’s preparedness for a V. destructor incursion is discussed in Chapter 2.
The ongoing risk of bee pests like Varroa arriving in Australia is high. Lindsay Bourke from AHBIC indicated that there are ‘between three and four’ detections of pest bees or bee pests at the border each year.
Australia’s biosecurity controls are focused on detecting these kinds of pests arriving at Australian ports and have so far been successful. However there is an additional risk that pests could arrive in Australia on bees that have been smuggled into the country:
There have been two cases prosecuted in Australia for smuggling. Both of them were for improved genetics … [T]here is work going on overseas to breed bees resistant to Varroa, so that is an incentive to bring them in. In those cases where we had the importation protocol for queen bees [the bee keeper] just did not want to go through that, so they tried to bring them in. One was through the post and the other one was the famous one that came in biros—in pens—and was intercepted.
Dr Paul de Barro from the CSIRO noted that the risk of Varroa becoming established in Australia is much higher if it arrives on smuggled bees:
We get smuggling of queen bees through the mail, and those bees may well have Varroa on them. Of course, they are going to be put straight into hives so it is in fact likely that establishment is much higher … [It is] a major issue, because it circumvents all our surveillance. The surveillance assumes a port of entry. But, of course, if you are getting bees smuggled in they are going to go into towns and cities, and will probably be well established before you actually have a chance of detecting them.
Two major bee biosecurity incursions have occurred in recent years. These are the arrival and establishment of the Asian honey bee in far north Queensland, and the recent detection of V. jacobsoni in Townsville.
The Asian honey bee was detected in Cairns in 2007 and an eradication program was begun which included:
attempts to destroy Asian honey bee colonies;
restrictions on the movement of managed bee hives and equipment; and
a notification system to more effectively locate Asian honey bee colonies.
However, the eradication program did not succeed. The Asian honey bee breeds rapidly, frequently relocates its nests and can travel long distances. It proved too difficult to locate and destroy all Asian honey bee hives, especially in remote terrain. Consequently, the eradication effort ceased and biosecurity authorities transitioned to a containment and management strategy with respect to the Asian honey bee. Information on the Asian honey bee management program can be found on the DAWR website.
The second major bee biosecurity incursion was the June 2016 detection of V. jacobsoni in a colony of feral Asian honey bees near the port of Townsville. While V. jacobsoni is considered to be the less threatening variant of Varroa, the detection nevertheless set off a substantial biosecurity response. Dr Kim Ritman from DAWR outlined the response:
The detection is reported to me, to my office, within 24 hours of it being detected. That then triggers a meeting of the Consultative Committee on Emergency Plant Pests, which includes the relevant industries—so, AHBIC in this case—and other industries, the state governments and the federal government … In the case of the jacobsoni, we react immediately and convene a committee to look at the technical feasibility and cost beneficiality of eradication. The combatant state— in this case, in Townsville, Queensland—puts together a response plan, which then goes for consideration to the National Management Group, which is heads of agencies and industry around the country, to okay the money to pay for it. In this case, it was $2.5 million or so to undertake that response.
Dr Ritman noted that on-the-ground eradication efforts commenced immediately and were underway in parallel with these administrative processes:
We had officers from the department collecting the bees, sending them off to CSIRO for analysis of viruses and inspecting them for Varroa … What is found is destroyed. Queensland immediately applies within its powers quarantine and movement restrictions so that you do not get managed hives being moved out of the area.
Trevor Weatherhead from AHBIC elaborated on the processes involved in the eradication effort:
The response when they first find the Varroa is to send the bees off for identification checking, and then they do delimiting surveys. They check to see if there are any more around. They have processes, one of which is called floral sweeping. This is where they go out and check the flowers, and if they find Asian bees—because the Asian bee is the vector for this particular Varroa—on flowers they then do what they call beelining. They convert the bees over to sugar and water, and then they watch where the bees go. They can follow them back and find the nest and destroy the nest in those situations.
Mr Weatherhead also noted the major role members of the public can play in an eradication program:
The biggest help is the public. A lot of publicity went out. As the officers were going through the streets, checking all the floral sources—the flowers—they would drop little notes in the letterboxes. Most of the detections—we are up to 10 now—have come through the public reporting the activity of bees.
The eradication effort with respect to V. jacobsoni in Townsville is ongoing.
Current biosecurity arrangements
In response to the high level of biosecurity risk, the Australian Government has established a strong suite of biosecurity protections. DAWR indicated that Australia is working very hard to mitigate the biosecurity risk it faces:
Australia has a world-class biosecurity system with robust processes in place across the continuum to mitigate the risks of exotic pests and diseases.
Australia’s biosecurity framework is risk-based, meaning that resources and effort are concentrated at points where the biosecurity risks are considered to be most acute. The determination of risk is made by scientific methods, according to DAWR:
The assessment of biosecurity risk is based on scientific analysis and is applied to vessels and cargo across import pathways. All vessels arriving and cargo imported into Australia must be reported to the department and are profiled for biosecurity risk. Vessels or cargo of potential concern may be assessed on documents, inspected or sent for mandatory treatment, depending on the nature of the biosecurity risk. Measures are also applied to manage non-cargo-related risks such as hitchhiker pests—and bees are included as hitchhiker pests.
In relation to honey bees, Australia employs a range of strategies to try to prevent biosecurity incidents. These include activities beyond, at, and behind Australian borders:
We have annual surveys in the Solomons, Papua New Guinea and Timor Leste, and also in the Torres Strait, which targets pest bees and bee pests. That gives us heads-up intelligence about what is in those locations … we have inspections of cargo and material coming into Australia … We then have the National Bee Pest Surveillance Program, administered by Plant Health Australia. That is targeted at ports of entry, with sentinel hives, lures, traps and so forth to try to get them. We have awareness onshore through industry and good relations with industry—sharing information on interceptions and detections so that any report can then trigger response processes … So we have a multifaceted approach.
In addition to DAWR's activities beyond and at the borders, Australia also has measures in place which aim to discover any bee pests which evade biosecurity detection. In relation to honey bees, this role is filled by the National Bee Pest Surveillance Program. (NBPSP).
The NBPSP is an early warning system designed to detect incursions of exotic bee pests and pest bees. The aim of the program is to ensure that any incursion of bee pests is detected quickly to give authorities the best chance of eradication or containment. The program targets bee pests such as Varroa mites, Tropilaelaps mite, and Tracheal mites, while also targeting exotic bee species like the Asian honey bee, the giant honey bee, and exotic strains of the European honey bee. It also works to prevent the spread of regionalised pests already present in Australia.
Although the NBPSP employs a range of surveillance methods, its key means of detection are sentinel hives and catchboxes. The hives and boxes are placed at high-risk locations around Australian ports and monitored regularly for invasive species and bee pests. In remote areas, catchboxes may be fitted with solar-powered sensors and cameras that can transmit data, enabling biosecurity authorities to monitor a wider range of areas at less expense.
Should an incursion be detected, Australia’s response plan is set out in the Emergency Plant Pest Response Deed (EPPRD). The deed is an agreement between PHA, the Australian government, all State and Territory governments and national plant industry bodies. It sets out arrangements for the management of an incursion beyond Australia's borders, and lays out processes which should occur when an incursion is detected with the goal of ensuring the eradication of the biosecurity threat.
In case of a detected incursion, measures taken in response will include scientific testing and identification checking, 'delimiting' surveys to uncover the extent of the incursion, detection of pest hives though on-the-ground checks and via public reports.