UC Davis and University of Reno faculty teams work together to understand the relationship between butterfly abundance and climate change, land use and pesticides

Climate change is affecting Sierra butterflies studied on land areas not exposed to human interaction, according to a recent study led by Chris Halsch, a doctoral candidate in the ecology, evolution and conservation biology program at the University of Nevada, Reno.  Halsch’s findings indicate that the changing natural environment—not direct human contact—is causing these effects, although butterflies are not always perfectly isolated from human contact.

         Halsch aided in writing the recent paper detailing these results, including a review of previous literature as well as new findings in the most recent observations of butterflies. The review consisted of findings from previous studies on the topic, which had no less than 10 years of continuous sampling, examined at least 10 species and took climate change into consideration, according to the study. 

The new findings were from a long-term time series that Dr. Art Shapiro, a professor in the UC Davis Department of Evolution and Ecology, started. Shapiro visited 10 sites across North Central California every other week for over 40 years to look for butterflies. It could be one of, if not the longest, insect-monitoring study in North America, according to Halsch.

         Over the past four years, Halsch collected butterfly data at higher-elevation mountain sites. He and his advisor, Matt Forister, are responsible for those sites and have provided the data from recent time series of the study to add to Shapiro’s observations.

         Shapiro is responsible for the creation of the Shapiro Transect, a series of 10 locations across North Central California where Shapiro monitors a variety of butterfly species activity. It benefits from the butterfly season occuring all year round at sea level, according to Shapiro.

         “At an interval of two weeks, I walk the transect and record everything I find,” Shapiro said.

         According to the data, changes in fauna and timing of butterfly activity were found to correlate with climate change. Each site included in the Shapiro Transect is matched to a long-term weather station and contains chronological data available on changing weather patterns. The Shapiro Transect is very important to the study, according to Halsch.

“It is one of the two best data sets we have in the world for understanding insects decline,” Halsch said.

         The other site referenced is overseen by the United Kingdom butterfly monitoring team. They have monitored hundreds of sites in their country for decades, while the Shapiro Transect mostly consists of Shapiro conducting the observations. Including the U. K. butterfly monitoring team eliminates the potential of an observer effect, which is a scenario where the observer has more impact on the findings than what the site has to offer.

         Butterflies have been the source of Shapiro’s research for the past 50 years.

         “They have certain advantages in this type of research,” Shapiro said.

         Butterflies are large enough to study with the naked eye and do not require special equipment to see them. They are also small enough to raise in large quantities in a laboratory setting, according to Shapiro.

         The conclusion of the study is that climate change negatively affects generalist butterflies—butterflies that can live in different environments— the most. The number of generalist butterflies, also called the weedy species by Shapiro, are declining in the mountains, and there are fewer moving up its slope. 

This is counterintuitive, according to Shapiro, because most people would think that specialist species, ones that can only survive in one type of environment, would have the most trouble with climate change. The colonization of the mountain depends on immigration from below, but there have been observations of long-term declines in butterflies generally in low elevations in California.

         The pesticide neonicotinoid, chemically related to nicotine, is an insecticide produced naturally by plants and is suspected to play a part in butterfly decline, according to Shapiro.

“Reducing the impacts of climate change is a societal problem, and it’s going to take so much work, but making an effort to plant better plants, reduce use of pesticides, not immediately remove weeds that might be good for butterflies will reduce impacts of other stressors because the threat of climate change is only increasing,” Halsch said.

The study of butterflies being negatively affected by climate change is part of a variety of other studies that include different insects that are also declining in population. Even when not all insect populations are declining, the phenomenon is widespread, according to Shapiro.

“The vast majority of insects are not pests, and the vast majority deliver important ecosystem services,” Shapiro said. “We should be concerned if insects are in decline, and we should try as good citizens to find what we as individuals could do to help.”
Written by: Francheska Torres —science@theaggie.org

Minimizing intensive energy operations in water systems can reduce water usage and costs comparable to current energy efficiency programs

In an innovative time where power and energy have evolved tremendously in the past few decades, efficiency and conservation have become new focal points, constantly being optimized in balance with costs. A study conducted by UC Davis’ Center for Water-Energy Efficiency illuminates the possibility of saving not only water but also energy and greenhouse gas emissions through water conservation programs.

Edward Spang—an assistant professor at UC Davis’ food science and technology department who played a pivotal role in starting the Center for Water-Energy Efficiency—explains the findings of a previous statewide study following the urban water conservation mandate back in 2015. Due to the mandate, all urban water utilities were required to reduce water usage by 25%. 

“We found that the cost [of water conservation programs] was competitive with direct energy efficiency programs,” Spang said. “That is to say that you can actually save water and energy at the same cost as saving just energy alone.”

In his most recent study, Spang conducted a case study on the Los Angeles Department of Water and Power (LADWP), a major water utility that has implemented water conservation programs, and by working with an individual public utility company, he reaffirmed the broad findings from his previous statewide study. 

“The study found that LADWP saved a considerable amount of energy through its water conservation programs,” according to a UC Davis press release. “Across the various scenarios, the estimated energy savings secured through water conservation programs (e.g., high-efficiency washing machines, toilets/urinals and irrigation systems) was cost-competitive with LADWP’s energy efficiency programs (e.g., more efficient lighting, HVAC and refrigeration systems).”

Though the findings offer a remarkably optimistic duality in saving energy and water, they highlight the complexity in measuring costs and energy savings purely due to water conservation programs—as Spang describes from a systems perspective—which, in turn, could be why many utilities have yet to adapt these programs.

“We’ve been working for a while to try to come up with methodologies to measure the amount of embedded energy in water systems,” Spang said. “This meant looking at a particular volume of water delivered to a customer, how much energy did it take to extract that water from groundwater, convey that water to a treatment plant, treat the water and then distribute it to the customer. You can actually trace the pathway of these water sources and come up with an energy footprint to deliver a particular quality of water to a particular location.”

Katrina Jessoe, an associate professor in the agricultural and resource economics department, offers an economist’s point of view as to why it can be difficult to adopt water conservation programs. 

“What the engineers find can differ from what the economists say,” Jessoe said. “The engineers tell us there are these huge savings from these programs, but the economist comes and looks at it, and finds that maybe that is not the case because behavior matters. Some water conservation instruments may yield energy savings, while some may not.”

Despite the many barriers and limitations that establishing water conservation programs may bring, the LADWP is a model that future conservationists and economists can follow to better understand and optimize energy and resource conservation in the future. 

According to Spang’s broad vision of what the future may hold for energy efficiency, California has done such a remarkable job with its programs that transitioning to another level of optimization of energy, and costs will be the next challenge.

“California, we have done such a good job that there’s not much low-hanging fruit as there used to be for these programs,” Spang said. “For example, changing out lightbulbs: We’ve done a really good job with that. And there are still lightbulbs we still need to change out, but at a certain point, we need to move onto the next phase of energy efficiency, which is a little bit more difficult. You can think of another analogy where you go from a lightbulb to the whole house, where you’re looking at window glazing and insulation.”

Indeed, water conservation may have opened a new door to this “whole house.” Jessoe highlights a holistic approach on water conservation, looking at agricultural users rather than just residential users, which may even further expand Spang’s findings.

“One thing we focus a lot on is residential water conservation. In California, urban users account for 20% of human water use while agricultural users account for 80%. The marginal cost of trying to wring out that last drop of water out of residential users is really high. So you might be able to, for the same cost, get a whole lot more conservation out of agricultural users.”

Written by: Brandon Nguyen – science@theaggie.org

Study reveals counties with increased number of cannabis dispensaries have decreased rates of opioid-related deaths

As COVID-19 continues to dominate public health concerns, another epidemic still remains prevalent in the background—the opioid crisis. According to the Centers for Disease Control (CDC), the U.S. saw the highest number of deaths within a 12-month period during the pandemic due to overdoses, the primary driver being synthetic opioids. Recent research conducted by Greta Hsu, a professor of management at the UC Davis Graduate School of Management, sheds light on a potential direction for researchers to take in addressing opioid misuse. 

“Given how serious the epidemic of opioid misuses and drug overdose deaths has become, we thought this was an important public health question worth investigation,” Hsu said via email.

When Hsu and her collaborator Balazs Kovacs, an associate professor of organizational behavior at the Yale School of Management, began looking at the increased prevalence of legal cannabis stores, they realized that looking at cannabis dispensaries on a county-level could shed light on whether the availability of legal cannabis had any implications on opioid misuse. 

They found that counties with a higher number of cannabis dispensaries were associated with reduced opioid-related mortality rates. Hsu elaborated that this was the case for both medical dispensaries, which only serve patients with a physician’s recommendation, and recreational dispensaries, which cater to any adult 21 years and older. 

Naileshni Singh, an associate clinical professor in the department of anesthesiology and pain medicine at UC Davis Medical Center, explained that opioids are commonly used in pain management, such as for cancer-related pain, acute pain and post-surgery pain. While the substance used to be the primary treatment for chronic pain in the mid 1990s and early 2000s, according to Stephen Henry, an assistant professor of general medicine at UC Davis Medical Center, present-day clinicians know that the long term use of opioids may not necessarily be better or safer compared to alternative treatments such as anti-inflammatory medicine or exercise-based treatments. Singh also emphasized the need for clinicians to understand more about how to treat pain with non-opioid based methods. 

“It’s not just prescribing a medication, but it’s encouraging patients to exercise, to engage in physical therapy, to engage with family members, to try other medications that are not opioid based, to lose weight, to get on a healthy noninflammatory diet,” Singh said. “There’s a lot of things that patients can do other than take medication to alleviate their pain.”

For the past couple of years, Singh has been incorporating more opioid education into the medical school curriculum so students can have more knowledge when prescribing and using opioids for medical cases. She believes opioids are an important aspect of pain management and have many benefits such as helping patients be more functional and less socially isolated. However, it is important for medical students to understand the balance between the risks and benefits of its use. In some cases, opioid use could result in respiratory depression, constipation, osteoporosis, unintentional overdose or death.

“You need to understand what the opioids can do, what the opioids can’t do and how it’s one piece of the bigger pain management puzzle,” Singh said. “So if the benefits appear to outweigh the risks, then it could be an appropriate therapy.” 

Henry explained that one of the barriers patients and primary care clinicians face when dealing with effective pain management is having difficult conversations about opioids and chronic pain, often involving mutual mistrust. Such barriers make pain treatment difficult in a climate where opioid prescriptions for pain are already strongly discouraged. 

“In some of my research, I found that many times primary care physicians can have a very difficult emotional conversation with a patient about opioids that leads them to be suspicious of all patients who are taking opioids for chronic pain, even though the majority of patients just want to get better treatment for their pain,” Henry said. “On the other hand, patients often have experience being stigmatized or mistrusted by primary care physicians and so can be on guard and suspicious of clinicians.”

He expressed that although opioid use disorder and opioid overdose are major public health problems, the vast majority of patients who are taking opioids for pain management only take low doses for short periods of time. He stated that it is important to be able to identify high risk patients, such as those with a history of a substance use disorder, in order to minimize opioid misuse. 

Hsu explained her study cannot demonstrate whether there is a causal relationship between increased prevalence of cannabis dispensaries and reduced opioid-related mortality rates, but may be able to help inform public health policies. While Henry stated that there haven’t been many studies looking at cannabis as a potential pain treatment option, he hopes regulations guarding it may be reduced for more research to be conducted with the substance. Singh also named cannabidiol (CBD) oil and tetrahydrocannabinol (THC) related products as possible alternatives. 

“Overall, we believe greater understanding [of] the public health outcomes of cannabis legalization on opioid misuse is needed so that policymakers can properly weigh the potential benefits versus harms of promoting cannabis legalization,” Hsu said via email. 
Written by: Michelle Wong —science@theaggie.org