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Feral honeybee researchers abuzz about potential breakthroughs
Insects are what make the agricultural systems in the United States and elsewhere in the Western world go ‘round. In particular, our food system relies on the Western honeybee, the most common species of honeybee worldwide. These honeybees’ most profitable and important work isn’t making honey—it’s pollinating crops such as apples in New York, cherries in Washington, squash and pumpkins in the Midwest, cranberries in Massachusetts, and blueberries in Maine.
“We have a lot of great native pollinators,” says Associate Professor of Chemistry Bill Collins. “We have about two hundred fifty species of bumblebees here in North America. Bumblebees in large part can be better than honeybees at pollinating. We have lots of solitary bees. We have flies. We have Lepidoptera. But we have adapted an agricultural system that does not allow for those species. What that means is that you need to bring in pollinators to do the work of the pollination.”
Native pollinators require a fully diverse ecosystem to survive; however, each of these crops exists today in a monoculture. So beekeepers truck their hives to each of these crops in season, and then truck them out again. Beekeeping in this way is a booming business; almond pollination in California each spring requires more than one-third of all managed honeybees in the country.
This way of agricultural existence hinges on the health of the entire honeybee population. But this way of pollinating monoculture agriculture by bringing the bees to the plants means that the bees themselves are becoming at risk.
“People are now starting to think that we have this issue, which is that we have a monoculture of bees,” Collins says. “All of these bees are coming from these few bee breeders, and we’re distributing them across the country. This has happened for the last several decades. As a result, we have greatly diminished genetic diversity of our honey bees. If they have diminished genetic diversity, then they might be more susceptible to all these other things happening to them.”
Talk to any passionate beekeeper—such as Collins, who keeps bees as a hobbyist in addition to the on-campus research apiary—and you’ll hear a list of the things possibly affecting the bees. Infections from the Varroa mite. Immunodeficiency. Changing beekeeping practices. Exposure to pesticides. Malnutrition.
All these factors have been implicated to some degree in colony collapse disorder. CCD is the phenomenon, experienced particularly in the last ten to twelve years, where a majority of a colony’s worker bees disappear and leave behind a queen and a few nurse bees in the hive. Out of the world’s approximately 83 million hives in 2014, according to U.N. FAO data, more than ten million were lost to CCD from 2007-2013.
In short, CCD both poses a threat to our agricultural systems, and remains a mystery that beekeepers and biologists alike are striving to solve. At Fort Lewis College, Collins and his students are researching angles into the genetic diversity and natural immunodefensive systems of the Western honeybee in hopes of promoting honeybee health around the world.
The wild world of feral bees
Collins’ research meets at the intersection of plant chemistry and honeybee health. “They are very intertwined subjects,” he says. “I am interested in how we can use plants to improve honeybee health. And that’s why my students and I are interested in feral bee colonies.”
Here’s the basic background to feral bees, once-domesticated bee colonies that now live in the wild without human support: the western honeybee was brought to North America during colonial times, and the species took well to living in the continent’s various climates. So when a colony would swarm, a portion of the bees set up a new hive in the wilderness.
The problem is that at some point, the Varroa mite jumped from another species of bee to the Western honeybee. The mite—or rather, the viruses it carries—obliterated many of the feral honeybees that were not being treated for the mites.
“The way we think about Varroa mites is like how we think about ticks and Lyme disease,” Collins says. “We don’t fear ticks, but we fear the Lyme disease they transmit. Similarly, these Varroa are transmitting these viruses, which are implicated strongly in colony collapse scenarios.”
The mites have hit feral colonies across the United States, which by definition are not being chemically treated for the parasites. The majority of feral colonies were wiped out, Collins says. But the small percentage that survived and continued to swarm and procreate offer potential remedies for protecting domestic hives from the infections of Varroa mites.
“I'm really interested in the idea that bees have this self-medication thing going on, where they seem to augment their own immune system with these anti-pathogenic, anti-microbial resins that trees produce, and they coat the insides of their colonies with it,” Collins says.
“The two directions our research is going in right now are: First, we’re interested in these plant resins. Can we think of natural, plant-based phytochemicals that might help bees? Because sometimes these synthetic miticides are damaging to bees too. And the other avenue is, do these surviving colonies have interesting attributes that they’ve adapted to their scenarios? Maybe we can learn about them and introduce more genetic diversity into our own colonies.”
A taste of their own medicine
In order to conduct research on feral bee colonies, Collins and his students first had to trap a feral bee colony. “Fortunately, we realized that Fort Lewis sits at a very unique position where we have a large amount of wilderness area,” Collins says.
So using a system of pheromone-baited swarm traps, they were able to relocate some bees from the undeveloped land around Durango to the 18-hive research apiary on campus.
"If we're ever to try and re-establish the health of the honeybee, we need to look towards things like what the feral colonies are able to do by themselves in their natural state.”
“The way you can do this is, when the bees swarm in the spring, the colony will divide, and they’ll try to find another tree to inhabit,” Collins explains. “So half the colony will stay in the tree, and the other half will leave and they’ll form a new queen.”
Next, they allowed both the offspring of the feral colony and the managed colonies to collect resins for the propolis in their hives. Propolis, also called “bee glue,” is a resinous mixture of saliva, beeswax, and these resins collected from various plants. The colony uses this propolis to close up holes in the hive.
But it appears to have other purposes, as well. “It actually suppresses and lowers their immune functions,” Collins says, “which sounds counterintuitive. But when you think about it, when you’re sick, the energy that it takes to get your immune system going is costly for any organism. So if bees are being constantly hit up by a bacteria or a virus, the thinking goes, maybe they put this propolis envelope in the hive as their immune system, so they actually have to expend less energy fighting the bacteria and they can do more things like forage.”
So the question Collins and his students posed is this: Do surviving feral colonies have a genetic disposition to collect plant resins that help them survive a parasitic infestation and stave off CCD?
By giving the feral colony and managed colonies the same availability of resources, these researchers found that the propolis produced by the two types of hives was distinctly different, both in composition and in concentration. Using gas chromatography and mass spectrometry, they can isolate specific active molecules for further research into their efficacy against particular parasites.
“It suggests what other people are seeing, that perhaps on a genetic level feral colonies are able to find and collect these prophylactic plant resins differently than managed colonies can,” Collins says. “If we're ever to try and re-establish the health of the honeybee, we need to look towards things like what the feral colonies are able to do by themselves in their natural state.”
Bee students
Not only does the wilderness surrounding Durango enable Collins to conduct feral bee research more easily than his peers in other locations, but at FLC, his students are able to engage in the entire research process as undergraduates.
“My students are actively involved in maintaining the research apiary,” Collins explains. “Everyone needs to learn how to do beekeeping as part of it. You have to keep these colonies going. But then, the research is two-part.”
Where the students participate depends on their interests. Some of them go out and find feral colonies by using historic beelining techniques. In turn, these same students are helping to set the traps where colonies are likely to swarm.
Other students are doing strictly lab work. “I had two students, both freshman going to sophomores now, who isolated a whole bunch of Varroa mites by pulling them off of bees, basically,” Collins says. “Then they actually take the molecules that we know we’re interested in, synthesize them in the lab, and coat the mites with them to see how many live. We’re essentially looking at mortality rates for the Varroa.”
Student researchers also tested the components of the propolis against a newly discovered bacteria strain from Wisconsin that might be implicated in colony collapse, as well. And other students worked with other faculty members conducting bee research. For instance, students work with Associate Professor of Biology Steven Fenster to do a genetic analysis of the different bees, and with Assistant Professor of Biology Ryan Schwarz on bee gut microbiomes and bee pathogens.
As for his own research, Collins is particularly excited about the results they’re seeing about the molecules in the feral colony’s propolis; he’s hoping to publish the research, with one of his research students as a co-author, in the near future.
“We have found a class of molecules that are very effective against Varroa mites, which is good because the pipeline for any kind of chemical treatment against Varroa mites is actually dwindling right now. A lot of the synthetic variants have some deleterious effects. They hurt the colony in other ways. So maybe a molecule derived from a plant, something bees would be collecting anyways—that is the center of the idea. We wanted to search from this class of molecules that the bees were already in contact with. Maybe we could find something that, if we just gave the bees more of it, could be used to affect Varroa health.”
There’s further research to be done, of course. For instance, Collins says he’s partnered with the USDA to test how the bee colonies themselves respond to different concentrations of these natural molecules. But the results so far have him feeling optimistic, and he’s thrilled that students get to be involved in all of his research.
“Everything I do has got students,” he says. “I think the most exciting part at Fort Lewis is getting students excited, exposing students to what real research is. Some students think research is kind of like a class. But it’s much more open ended than that. There’s no necessarily right answers. There’s a lot of failure. But getting people really excited about getting into science and doing research is easily the most important part of what I do.”