Research is still ongoing to identify the cause of the colony loss reported in early 2025 — elsewhere, new methods look to help beekeepers monitor their colonies’ health
By KATELYN BURNS— science@theaggie.org
Project Apis m. reported massive colony loss in early 2025, estimating around 1.6 million colonies lost in a report from April — a large number considering the National Agricultural Statistics Service (NASS) estimated the total number of United States colonies is 2.7 million. While there have been continuous losses of 30 to 50% in previous years — such as a colony collapse disorder first noted in 2006 — the recent losses have been especially drastic, drawing concern regarding food security, among other things.
While research to identify the cause of this most recent colony loss is ongoing, past research shows that bee decline is often driven by pests, pathogens, pesticides and poor nutrition.
Dr. Elina L. Niño, the director of the E.L. Niño Bee Lab and an extension specialist for the University of California working primarily with beekeepers, commented on the bee decline and the role of beekeepers.
“What we have come across in the past, and the reason why we started the California Master Beekeeper program, is that people get excited and want to help but don’t get the education,” Niño said.
For example, Varroa mites, a parasitic pest found in bee colonies, are one of the challenges that beekeepers have to manage. If beekeepers aren’t properly educated, their hives could become a breeding ground for these mites resulting in “mite bombs,” high numbers of Varroa mites that can end up spreading to neighboring hives and contributing to colony collapse. Varroa mites can also vector viruses to bees, such as the deformed wing virus.
“What we do know, from prior research, is that proper nutrition is really important to be able to deal with a lot of different potential issues,” Niño said.
Past research has shown that proper nutrition has helped bee colonies recover. Natural spaces, like public forests or federal and state lands, often have a lot of forage for bees. Additionally, planting flowers — which produce either nectar, pollen or both — are beneficial to bee colonies. Planting in ways so that they will bloom at different times of the year is beneficial for all pollinators, including honeybees, and this is especially important in places like California, where the mild weather year-round means that bees don’t fully go dormant. The UC Davis Bee Haven is a model for what a pollinator-friendly garden could look like in Northern California.
Regarding forage, the biggest concern is pesticide use. Surprisingly, the largest “misusers” of pesticides are actually urban gardeners — or “backyard gardeners” — or any gardeners not agriculture-related. Pesticides are easily purchasable at any local Lowes or Home Depot, but “backyard gardeners” aren’t necessarily taught the importance of following the labels.
An experienced beekeeper can detect these problems. For example, some diseases can even be smelled. However, while an experienced beekeeper is irreplaceable since human senses are usually able to pick up on things that machines cannot, technology continues to develop.
“One of the biggest costs for beekeepers is labor,” Niño said. “So, if there’s any way to reduce costs in that way, that would probably be beneficial for the beekeepers.”
In a paper published in early 2025 in the Association for Computing Machinery Transactions on Knowledge Discovery from Data journal, a team developed a system utilizing low-cost sensors to predict problems in the hive.
The team included Shamima Hossain, a Ph.D. candidate in the Electrical and Computer Engineering Department at UC Riverside, Dr. Christos Faloutsos, a professor in the Computer Science Department at Carnegie Mellon University, Dr. Boris Baer, a professor of entomology at UC Riverside, Dr. Hyoseung Kim, an associate professor in the Electrical and Computer Engineering Department and the chair of the computer engineering program at UC Riverside, and Dr. Vassilis Tsotras, a professor in the Electrical and Computer Engineering Department at UC Riverside, discussed their system and their decision to focus on temperature.
The system uses the hive health factor, which is computed from their Electronic Bee-Veterinarian Plus (EBV+) model using the environmental temperature and the hive temperature as inputs.
“The health factor is how close the actual temperature is to the ideal temperature of 35 [degrees Celsius],” Faloutsos said. “The bees can operate like an air conditioner or a heater.”
If the temperature is close to ideal, the bees are considered strong and healthy, and they can take care of themselves. If the temperature is off, indicating the bees are not thermoregulating, there might be problems in the hive — such as pests, pathogens, pesticides or poor nutrition.
“We already know that if bees have certain diseases, they can create social fever,” Tsotras said. “It’s very similar to your own body — if you have an infection in your body, the temperature of your body is increased to activate your immune system, [and] bees do the same — they use temperature as an immune defense.”
The system gave flags, changes that didn’t drop below the thresholds and warnings, alerts that occurred when changes caused the health factor to drop below the threshold. In the paper, they noted temperature changes resulting in flags or warnings following stressors or unexpected events, such as hive openings, sensor rechanging or replacements and mite treatments.
This paper used temperature changes to quantify general hive health, but the team hypothesized that eventually identifying specific activities or issues could also be possible.
“We basically quantified how healthy the bees are solely by temperature,” Kim said. “We are currently working on distinguishing different activities just using temperature, […] because [our hypothesis is] that different activities actually have a different pattern in the temperature changes.”
The system can allow beekeepers to remotely monitor many hives. Only when the warning is raised do beekeepers have to take action, decreasing the frequency of manual inspections.
A reason for focusing on temperature was that temperature sensors are generally much cheaper than other sensors and require less power to run.
“Accessibility and cost efficiency is really important for deploying these technologies across different kinds of beekeepers,” Kim said.
While a cheap device using off-the-shelf components was developed to better help beekeepers keep costs low, their research wasn’t focused on the sensors themselves.
“We developed a method [that] can be integrated with any temperature sensor found in the market,” Hossain said.
They are continuing to improve upon the system, working with several associations of beekeepers operating in Southern California and organizing conferences to give updates and receive feedback.
“This is something that the beekeepers are engaged with and they can give feedback,” Baer said. “The beekeepers are really excited about this.”
Written by: Katelyn Burns— science@theaggie.org
