Flowers of the snow gum. Flickr photo by John Tann.

Martha takes me out to scout the bloom a couple of times. It’s basically a tree road [...]]]> In her second installment about beekeeping in Australia’s Outback, Maggie tells about scouting the eucalypt bloom and the threat of the Asian honey bee, Apis cerana.

Flowers of the snow gum. Flickr photo by John Tann.

Martha takes me out to scout the bloom a couple of times. It’s basically a tree road trip. We’re sizing up snow gum, blue gum, stringy bark, red gum, and ribbon gum that wears its loose bark like a boa. We observe that 70% of the grey box are 80% budded. I’m not exactly sure what this means, but Martha is pleased by the news. The car ride is a six-hour excursion, and in between tree trips Martha tells me about the impending invasion of Apis cerana.

Martha has served the beekeeping industry in several capacities, holding executive office in various apiary associations, even lobbying Parliament in Melbourne. She is a well-connected leader in a tight-knit industry, and so she recognizes emerging threats, and she understands their implications. Cerana is a problem, she explains.

The first arrival

Bark of the ribbon gum. Photo by plantthis.com.au.

Cerana has been known to swarm up to 10 km every 2-3 weeks, and it establishes small colonies that are difficult to spot. Currently, the Department of Primary Industries (DPI) coordinates a containment program in Cairns where volunteers beeline from bait stations, monitor rainbow bird and bat feces for evidence of bees, and maintain a 100 km x 30 km containment zone. However, funds are too short for full-scale eradication, and commercial beekeepers anticipate its inevitable spread.

A threat to honey bee exports

The invasion of Apis cerana poses several difficulties for Australia, not least of which is its alarming tendency to nest in mailboxes. According to the beekeepers I interviewed, cerana is aggressive toward native bees and other honey bee species. It recently robbed out 2,000 managed mellifera hives in the Solomon Islands. Cerana is also considered to be a poor pollinator for human purposes. Furthermore, a cerana-mellifera cross might endanger Australian export of packages and queens.

Apis cerana. Wikimedia Commons photo by Azman.

Because Australia’s bee season coincides with the California almond bloom, Australia sends loads of bees to the U.S. every January and February. The invasion of cerana endangers this partnership because California cannot import bees that might have hybridized with an invasive species.

The invasive Asian bees in Australia are of Indonesian origin, though they came over from New Guinea. Actually, they were brought to New Guinea when authorities were trying to make good for displaced native populations, but that’s another story.

This invasion may sound like another case of globalization run disastrous, but in the scheme of things, the situation could be much worse. Let’s keep this in perspective: the cerana invasion is inconvenient by our standards because it poses a threat to the livelihoods supported by mellifera—a well-established but (let’s not forget) equally invasive species, introduced to Australia in the 1820s.

Most importantly, the parent swarm that established in Cairns did not bring Varroa with it, so Australia remains a sort of beekeeping oasis, where big, healthy bees still bubble out of boxes with a rigor that continues to impress my American eyes.

Maggie
HoneyBeeSuite

Invasion of Apis cerana could disrupt Australia’s honey industry. Photo by Maggie.

For more information, check out this recent report conducted by the Asian Honey Bee Program in Cairns: http://asianhoneybee.net.au/wordpress/wp-content/uploads/2012/02/AHB-Behavioural-analysis-report.pdf

I was out in the woodshed this morning splitting logs when I heard the faintest scritch, scritch sound coming from the walls. The woodshed has three sides, all made from cedar, and when I put my ear to the wall it sounded as if [...]]]>

Yellowjacket pheromone lure vs cedar shed: the shed wins

I was out in the woodshed this morning splitting logs when I heard the faintest scritch, scritch sound coming from the walls. The woodshed has three sides, all made from cedar, and when I put my ear to the wall it sounded as if the noise was inside the boards. Curious, I set aside the splitting maul and went in search of the scritch, scritch.

What I found surprised me at first. The outside wall was inhabited by half a dozen yellowjackets that seemed to be licking the boards. They weren’t queens, but probably the first progeny of a new queen. At first I was confused until I remembered that yellowjackets chew wood into a pulpy material and use it to build their nest. The cedar—being unfinished—was a perfect material to chew into a paste. The sound was made by their mandibles ripping the wood fibers.

I decided to kill them—after all, either I kill them or they kill my bees. It took all of about 90 seconds to find my butterfly net but by then they were gone. Annoyed that I lost them, I went on a hunt. By circling the house a few times, I was able to net two queens under the eaves within about five minutes. At least I assume they were queens because it is early in the season and they were monster yellowjackets—about twice the size of the workers I had just seen.

This was a good catch as it may have saved me from having to deal with two voracious hives by fall. This is just a reminder to watch out for those ladies in yellow. What looks like just two or three annoying wasps today may be two or three thousand even more annoying wasps later in the year.

By the way, did I mention there is a fresh (as of yesterday) yellowjacket pheromone lure hanging three feet away from the shed? Believe me, they were totally unimpressed.

Rusty
HoneyBeeSuite

In [...]]]> A small parasitic fly, Apocephalus borealis, may turn out to be one player in the failing health of honey bee colonies in North America. The parasite, a type of phorid fly, has long been known to parasitize bumble bees and paper wasps, but recent research shows that it may also attack honey bees.

In an article published yesterday in the journal PLoSOne, researchers explain that the tiny adult female fly lands on a honey bee abdomen and lays eggs by placing her ovipositor into the bee. The entire process takes two to four seconds. Seven days later the adult phorid larvae emerge from the area between the bee’s head and thorax. One to thirteen larvae emerge and leave the dead bee behind. The larvae then pupate elsewhere.

Oddly, honey bees parasitized by the phorid flies are attracted to light. Individuals are found to abandon their hives at night and fly toward sources of light where they remain until they die. In fact, it was large numbers of dead honey bees around lights on the campus at San Francisco State University that lead to the discovery of phorid fly activity in honey bees. Also of interest is the fact that many of the phorid flies were found to test positive for Nosema ceranae and deformed wing virus—pathogens often associated with dead colonies.

The authors of the paper speculate that the native phorid fly has recently evolved to accept the non-native honey bee as a host. If the fly had long been a parasite of honey bees, adult phorid flies, their larvae, or accumulations of dead bees around lights would have been noticed before now. As they point out, the honey bee is one of the most studied creatures on earth so it is doubtful this fly would have escaped detection.

If the fly has indeed shifted hosts, it is bad news for beekeepers. Unlike bumble bees and paper wasps—creatures without huge populations—a honey bee colony can provide a vast breeding ground for the flies. And at one to thirteen larvae per bee, it wouldn’t take long for the flies to overwhelm a colony. Furthermore, this tremendous population of flies could leave the hive and harm bumble bees and perhaps other wild bees as well. Scary stuff, great material for horror flicks.

I urge you to click on the link to the original article and enlarge the photo of a phorid larva leaving a bee. But I warn you, the image is graphic. It is enough to make me sick.

Rusty
HoneyBeeSuite

To kill the moths, you must monitor both time and temperature. For example, the Mid-Altantic Apiculture Research and Extension Consortium (MAAREC) publishes the following guidelines to kill both species [...]]]> Contrary to popular hearsay, freezing will kill all life stages of both the greater wax moth (Galleria mellonella) and the lesser wax moth (Achroia grisella).

To kill the moths, you must monitor both time and temperature. For example, the Mid-Altantic Apiculture Research and Extension Consortium (MAAREC) publishes the following guidelines to kill both species of wax moth:

20 degrees F for 4.5 hours or

5 degrees F for 2 hours.

Similarly, the Department of Primary Industries in Victoria, Australia advises

-6.7 degrees C for 4.5 hours or

-12.2 degrees C [10 degrees F] for 3 hours or

-15 degrees C for 2 hours

These numbers convert exactly. Nevertheless, beekeepers come up with all kinds of wild stories about freezing them for weeks on end, only to have the caterpillars start crawling around when the frames thaw. Don’t believe it.

Here are some points to consider if you freeze your frames for wax moth control:

• Check your freezer temperature with a reliable thermometer–don’t depend on the dial.

• Measure times from the point when the frames, combs, wax, or super reaches the desired temperature. Don’t start timing from the moment you put them in the freezer.

• Remember: if you return thawed frames to a super that was not frozen, re-infection can occur immediately.

• The same is true if you return frames to an area that contains adult wax moths, such as a storage building or honey house.

• If you wrap frames tightly in plastic wrap before freezing–and leave them wrapped afterwards–you can protect them from re-infestation. Wrapping also keeps condensation from forming on the combs and frames while they return to ambient temperature.

Freezing times don’t have to be exact as long as you meet the minimums. For example, my freezer is 9 degrees F. I just wrap my frames in plastic and freeze overnight . . . or over 30 nights. There’s no need to create an ordeal.

One reason the myth persists is that some beekeepers have reported that wax moths survived the winter in their hives in spite of the fact it was less than 20 degrees for weeks on end. This is most likely true because it is not 20 degrees inside a healthy beehive. The cluster keeps the wax moths warm and cozy all winter long. But as long as the colony remains healthy and strong, it will destroy most of the moths as it expands in spring.

So just remember, wax moths are not an inexorable pest destined to take over the world–they are both predictable and manageable. When the day comes that they can drop me in the freezer, then I’ll start to worry.

Rusty

HoneyBeeSuite.com

Dave at Georgia Wildlife Services, Inc. wrote to [...]]]> After Monday’s post on yellowjackets I learned a lot about wasps. A representative of the Rescue Corporation–the people who make those plastic yellowjacket traps that I love–sent a positive i.d. on my nest: Vespula vulgaris. These are known as common wasps or, in North America, yellowjackets.

Dave at Georgia Wildlife Services, Inc. wrote to say the nest and surrounding envelope is called a carton. The nest is made from chewed wood mixed with saliva. Although it looked like wood shavings to me, it disintegrated when I touched it. So now this all makes sense.

When I went back up the hill the next day to look at the nest again, it was gone. Some of the wood and saliva material was still stuck to the branch but the rest had disappeared. I’m assuming the brood is especially yummy to things like opossums, raccoons, birds, or many of the other critters that live here in the Northwest woods. It’s no surprise that we don’t often see things like a fallen nest–what is a catastrophe for one species is a windfall for another. Such is nature.

A special thanks to everyone who helped with words of wisdom and species identification. I learned a lot from you all.

Rusty
HoneyBeeSuite.com

Other things can cause an occasional case of deformed wings [...]]]> Deformed wing virus (DWV) is one of the viral diseases associated with Varroa mite infestations. Although the disease is also found in colonies not infected with Varroa, it appears to be both more common and more destructive in colonies where mites are well established.

Other things can cause an occasional case of deformed wings and a diagnosis is impossible without laboratory tests. However, if you see a young bee with distorted, misshapen, twisted, or wrinkled wings, there is a good chance you are seeing the results of deformed wing virus.

In untreated hives, the Varroa mite population skyrockets in late summer and early fall. The mites had all spring and early summer to build up and now, when the drones are being evicted and the honey bee population is shrinking, the number of mites may overwhelm the number of bees. When the viruses also become concentrated in the remaining bees, symptoms are more likely to be apparent to beekeepers.

Bees with deformed wings do not live very long. The one shown below wandered out of the hive this morning and was fluttering her misshapen wings and running in a circle when I found her.

Rusty

A honey bee with severely deformed wings