麻豆视频

CU Boulder entomologist studies how to protect nature鈥檚 most important pollinators from deadly parasites

Samuel Ramsey, an assistant professor of evolutionary biology at the 麻豆视频, is renowned for his expertise and effervescent enthusiasm for everything related to bugs. He's made a cicada music video on his 鈥淒octor Buggs鈥� YouTube channel and appeared on CBS Mornings to warn the public about spotted lanternflies, a destructive invasive species.

But perhaps Ramsey鈥檚 most important contribution to science has been his groundbreaking research on deadly parasites causing a steep decline in the honey bee population. Through his public appearances and nonprofit, the Ramsey Research Foundation, he鈥檚 also raising awareness about how we can change our international response to help nature鈥檚 most important pollinators survive.

The importance of bees to life on Earth can鈥檛 be overestimated. Through pollination, they help sustain the life cycles of wildlife habitats and produce one-third of the global food supply, including apples, coffee, nuts and potatoes.

鈥淲ith the sheer number of people and the amount of food that we want to grow on a regular basis, it requires us to dramatically increase the efficiency of agricultural systems, and that is what honey bees are built for,鈥� Ramsey says. 鈥淚t鈥檚 important for how we do life.鈥�

Studying a deadly parasite

Ramsey made his first splash in the scientific community when he was a doctoral candidate at the University of Maryland, where he researched the deadly bee parasite听Varroa destructor. Entomologists had long held that听痴补谤谤辞补听fed on bees鈥� blood, but Ramsey realized that this picture of听痴补谤谤辞补鈥檚听feeding habits was incomplete.

鈥淢y path to studying honey bees is a bit circuitous because I became obsessed with the听Varroa听mites before I became obsessed with honey bees,鈥� Ramsey says. 鈥淧art of what drew me to them was the fascinating history of how they got here and how they became such a dominating parasite on this planet.鈥�

When Ramsey finished his dissertation, he presented a new picture of听Varroa: Imagine a tick as large as a Frisbee lodged onto your body, transmitting crippling viruses; but instead of sucking your blood, it dissolves and feasts on your liver. This is what the听Varroa destructor听mite does to honey bees, and the mites have spread from Southeast Asia to the rest of the globe in a matter of just decades.

鈥淭here was a time where听Varroa听was restricted to just a tiny region of the world. But there was a host shift several decades ago when people started sharing brood from听Apis cerana听(the Eastern honey bee) with听Apis mellifera听(the Western honey bee) to make the Western honey bee colonies 鈥渟tronger鈥� in the area, Ramsey says.

鈥淪outheast Asia is the only region of the world where every single honey bee species exists. That's the cradle of civilization for them, except for the Western honey bee, which was brought back in鈥� by humans, Ramsey explains. When the Western honey bee branched off and evolved outside of Southeast Asia, 鈥渢hey lost a lot of their parasite suppression genes.鈥�

The Western honey bee now lives听on every continent except Antarctica as a domesticated insect. 鈥淎nd so now听Varroa, as of last year, fully has a cosmopolitan distribution by having finally reached Australia,鈥� Ramsey says. The losses have been devastating: Last year, North America lost 48% of its honey bees, with听痴补谤谤辞补听as the main driving force.

Ramsey鈥檚 discovery of听痴补谤谤辞补鈥檚听food source being bees鈥� fat body tissue, and not their blood, helped generate a new understanding of how听痴补谤谤辞补听thrives across the globe, which could chart new paths to protecting Western honey bees.

A new mite emerges

Since his dissertation, Ramsey鈥檚 research has shifted to a new parasite threatening听痴补谤谤辞补鈥檚听global dominance over bees鈥攐ne that is even faster and more efficient in invading colonies and reproducing its species:听Tropilaelaps.

尝颈办别听Varroa,听罢谤辞辫颈濒补别濒补辫蝉听was originally contained in Southeast Asia until it jumped hosts from听the giant honey bees to Western honey bees.听It听emerged later than听Varroa听and is currently spreading around the planet in a similar pattern.

鈥淭he possibility that听罢谤辞辫颈濒补别濒补辫蝉听can take over is quite substantial,鈥� Ramsey says. 鈥淲hile honey bee losses for some countries they鈥檝e entered were around 2% or 4% per year, those losses have now gone up higher than 64%. That is really devastating for the beekeeping industry, economy and ecology of those areas.鈥�

础濒迟丑辞耻驳丑听罢谤辞辫颈濒补别濒补辫蝉听poses a new threat to the global honey bee population, many nations have shown reluctance to tracking its spread.

鈥淣o one wants to be blamed for听罢谤辞辫颈听mites going from their country to another. So, for some of these regions, it has been difficult to convince people to do proper reporting of whether those parasites have been in their borders. They might not be able to trade bees and bee products freely to other countries because of the concern,鈥� Ramsey says. 鈥淭here are geopolitical concerns that are all pulled into that.鈥�

Another major obstacle to international research听has been the hesitance of wealthier nations to invest resources in other countries to study and manage the transmission of听Tropilaelaps.

鈥淪o little research was conducted on this organism when it was transiting through what we call 鈥榙eveloping nations,鈥� which is not my favorite term in the world, because these organisms were not impacting major economies,鈥� Ramsey says. 鈥淯nfortunately, that particular way of looking at things reduces people down to just their GDP. It doesn鈥檛 account for the importance of those human beings, their livestock and their bees.鈥�

奥丑别苍听罢谤辞辫颈濒补别濒补辫蝉听reached Pakistan about three decades ago, the country experienced a 100% loss of its western honey bee population. 鈥淲e have ignored it knowing it has the capacity to do that kind of damage,鈥� Ramsey said at the 2023 American Beekeeping Federation Conference.

Making research progress

Despite these challenges to international research on听Tropilaelaps, Ramsey and other entomologists have made recent headway in conducting research on the mite in Thailand. With donations to the Ramsey Research Foundation, Ramsey was able to fund his investigation into the behaviors of听罢谤辞辫颈濒补别濒补辫蝉听inside highly protective honey bee brood cells. This work is currently in review for publication.听

鈥淚nside the colony, there are these hexagonal cells that can be used to either store food or store the developing bees,鈥� Ramsey says. 鈥淣urse bees will create a wax covering over the cells when their larva reaches a certain age and starts to transition towards being a pupa. It鈥檚 at that time that听罢谤辞辫颈听mites are able to smell the age of the immature bees and jump into the cell.鈥�

Once inside the wax-sealed cells, mites are protected 鈥渇rom basically everything,鈥� including pesticides and the adult bees themselves. 鈥淚 quickly realized anything that won鈥檛 penetrate that wax capping is not going to be effective at controlling those mites,鈥� Ramsey says.

鈥淪o we started looking at different forms of treatments that could penetrate the capping and go after them, Ramsey says, adding that in the United States, a substance called formic acid has been shown to reduce the mite鈥檚 population substantially.

Ramsey and other scientists have been experimenting with other possible treatments that include applying heat to the brood cells to control听Tropilaelaps. 鈥淚t could potentially be a promising nonchemical means of treating this set of organisms,鈥� Ramsey says. 鈥淲e鈥檒l have to see more data.鈥�

Learning pandemic lessons

Although Ramsey thinks the international response has been timid in solving the growing crisis, perhaps some lessons have been learned from the COVID-19 pandemic.

鈥淲hen COVID-19 hit, I think it laid bare just how unprepared many of us have been for something like this,鈥� Ramsey says. 鈥淪o, thankfully, groups like the United States Department of Agriculture APHIS (Animal & Plant Health Inspection Service) and National Geographic have partnered with me, noticing that I have a lot of passionate for this subject and optimism that we can win this time! I鈥檝e already built out infrastructure in my research apparatus in Southeast Asia to study these things, so all the pieces are there.鈥�

Those partnerships support research about these organisms and contribute data to emergency response plans, Ramsey says. 鈥淲e鈥檝e picked up the pace and I think before the听罢谤辞辫颈听mites arrive, we will have a solid emergency response plan in place.鈥�

Much remains unknown about听Tropilaelaps, but Ramsey is currently raising funds through his Fight the Mite Initiative to conduct more research on the parasite across the globe. The Ramsey Research Foundation shares critical data with experts and the public alike to help stop this mighty mite.

鈥淲e are working really hard to make sure the general public has greater access to this kind of information,鈥� Ramsey says. 鈥�(I try) to do everything I can to make sure that I鈥檓 holding the door for others.鈥�

鈥淚t is my sincere hope that as we try to make research more broadly available, as we try to find funds to build up these communities, more and more of the general public will be behind us in these initiatives and provide their support whenever possible.鈥�

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Ramsey is the Marvin H. Caruthers Endowed Chair for Early Career Faculty at CU Boulder. You can learn more about his research and initiatives at the Ramsey Research Foundation.