RMBL research used for new article on changing climate cues

Predicting the future of wildflowers, birds, others in the East River Valley

[  By Katherine Nettles  ]

They say timing is everything, and a newly published paper based on collaborative research studies at the Rocky Mountain Biological Laboratory (RMBL) demonstrates how that is certainly the case in the high alpine environment of the East River Valley. A lupine flower will open at a precise point in time, for example, based on cues from the climate around it—and that lupine will rely on other biological organisms, such as pollinators, receiving related cues at the same time for both to thrive and propagate. 

Studying these cycles, or phenology, was the driver of a project to collect data from RMBL researchers and results have indicated that changing climate cues might alter and challenge the synchronicity of certain flora and fauna, including the renowned wildflowers and overall ecosystem of the North Valley. 

The paper, titled “Current and lagged climate affects phenology across diverse taxonomic groups” was published in the prestigious science journal Proceedings of the Royal Society B by lead author Dr. Rebecca Prather and more than a dozen co-authors. 

 As RMBL director Dr. Ian Billick summarizes, “One of the advantages of bringing scientists from around the world to work at RMBL is that they can integrate individual research projects to generate collective insights.” He says scientists have always collaborated at RMBL, and “We’re hearing from scientists that they want more cross pollination.”

The paper brings together many of those scientists to describe how wildflowers, birds, beetles, salamanders, ground squirrels, butterflies and other species found in the East River Valley are responding to cues from the changing climate to change their own seasonal activity. 

The massive effort combined data from 15 scientists who have worked at RMBL for as long as 52 years, representing 30 plant, 25 insect, one amphibian, two mammal, and 16 bird species, and 10,812 phenological events across up to 45 years from 1975-2020. The project also used climate data from Gothic and Crested Butte to explore how responses to climate cues differ among class, family or species and whether climatic variables from past growing seasons can be good predictors of future timing.  

One of the paper co-authors is Dr. David Inouye, a long-time RMBL researcher specializing in wildflowers. “I’ve spent essentially my whole career working at RMBL and was fortunate enough to start some of my projects in the mid 1970s…so that makes it a valuable record,” he says. His longest running study, the timing and abundance of flowering wildflowers, began in 1973.

“The reason we were interested in studying flowers back then was hummingbirds and bumblebees,” says Inouye. “Nobody was really thinking about climate change that far back. It was just fortuitous that we had those records.”

He says one of the somewhat unusual characteristics of RMBL is that it has fostered several long-standing projects such as marmot and wildflower studies. He also notes the variety of researchers. “There are a number of other people, including other co-authors of this paper, who also have long term records about the organisms that they study, including butterflies, salamanders, other things,” says Inouye. 

This wide variety of data is where Prather came in. A post-doctoral candidate in ecology and evolutionary biology at the University of Oklahoma at the time, RMBL hired Prather to help with the daunting task of integrating individual research projects from different scientists at RMBL over the past 50-plus years.  

“We asked her to try to pull together whatever she could on phenology,” says Inouye. “It involves such long-term work and it involves such a diversity of species, because of all these different researchers at RMBL are doing their own thing but in our shared environment. We haven’t collaborated closely in the past. But here we could find a common element which affects the subject of climate change. It gives us more of a landscape overview of, ‘how are the plants and animals changing in this area?’”

Prather recalls seeing the job posting, having never been to the area while growing up in Texas and pursuing her education in the south. “I heard it was a great field station,” she said, and quickly came to the same conclusion when she visited in 2020. 

RMBL hired her to work in equal parts on data synthesis and flower phenology, living at the field station in Gothic from May through August in 2021 and 2022. 

“I started talking to the researchers before I got there, but then living at the field station, and having means to make those connections makes all the difference. It is rare that so many people have been collecting long-term data in the same location. To collect and draw conclusions from that was neat.

“It was a lot of work. But I really like data, so it was fun,” says Prather. “I think the challenge was that a lot of these researchers started their research not to study phenology, so datasets varied in range, type, etc.”

While some data sets were usable right away, she said some were more challenging, such as scanned PDFs. “And a lot of it is just talking to project investigators, getting to know them and what they study,” she says.  

While the data Prather collected may have at times seemed like apples and oranges, “I worked to make everything apples,” she says, and focused on when each particular species was doing the specified biological activity, “just the timing of those events.”

Although Prather is now in Florida working  as a USDA post-doctorate fellow, she says her time in Gothic was very rewarding and she much prefers the summers in Colorado.

“It was amazing to be at a field station with so many people and different scientists and cutting-edge science happening. It was a new experience. It felt like I was at summer camp, honestly.”

Findings: longer fall and earlier spring

Prather and her co-authors found several notable results, such as how, since 1975, the average summer temperature at the study site has increased by 0.4° Celsius each decade, while fall temperatures have increased by 0.2 °Celsius per decade; snowmelt dates are trending earlier over time by 2.4 days per decade; and the first spring activity has advanced significantly with earlier snowmelt dates across all the species examined except migratory birds (a RMBL memo notes that this makes sense because bird migration is determined by cues along their travel and not just by their breeding grounds here in the Gunnison Basin).

 “Something I heard a lot was that snowmelt is earlier, and driving phenology. This paper looked at many environmental drivers, like fall temperatures, fall precipitation. While snowmelt and spring temperature are important, other climate factors are equally important and driving activity of different organisms,” Prather summarizes. “For example, fall is getting longer and spring is starting earlier. It can disrupt the synchrony of all these different groups. I think everything is more complicated than it seems.”

Some inconsistent responses to changing climate cues may have long-term implications, like how prior summer precipitation delayed the first activity of some insects but advanced activity of some amphibians, mammals, and birds. 

“The fact that not all species are responding identically to the changing climate means that in the future some current interactions, such as those between particular wildflowers and pollinators, may no longer occur. 

“Migratory hummingbirds may no longer arrive while glacier lilies are in bloom. Correspondingly, new kinds of interactions will characterize the future East River valley ecosystem as new species move in and current species change their activity periods,” according to a co-author synopsis of the paper.  

The synopsis also makes clear that more work is needed to learn which cues drive the whole spectrum of seasonal activities rather than just their beginning. “For example, the first date of flowering by a wildflower may not be a good predictor of its peak flowering,” it states. 

The project also found that there were more important climate drivers of timing cues than previous studies have found, that the most important cues could differ among species, and that the previous season’s climate could have a significant influence on those of the future.

As Billick puts it, “It’s difficult to predict what happens with these ecosystems in the future.” But he notes that bluebells are moving higher in elevation, and butterflies are at times passing over areas they once visited.

Family ties and future projects

RMBL is the subject of continued scientific interest not only for its newest paper but also for other elements to the work being done in Gothic. One of those is the Inouye family. In addition to David and many others who contributed to the paper are two co-authors from David’s own family. “I’m fortunate that two other people on that paper are my son and his wife, who started to do research in Gothic about 10 years ago as well,” he says. 

Inouye’s granddaughter Miyoko has grown up spending her summers in Gothic and attending the science camps they offer. She is now in middle school and helps her parents and grandfather when in Gothic. “She knows a heck of a lot of biology. She helps me catch hummingbirds,” says Inouye, among other tasks. The family connection will be the subject of an upcoming feature in National Geographic this spring. 

Billick says there is also a permanent installation coming soon to display historic Ute scientific methods, a nod to the Ute’s native history in the area. And there is always the search for continued financial support, whether from federal, state, regional or local investors in science.

“I don’t think this paper could have happened without an anonymous donor to RMBL who wanted to support this work,” says Prather. The hope is that post-doctorates like her can continue to visit the field station and keep up the collaborative data sharing, as well as other research opportunities. 

RMBL has also received grants from the National Science Foundation to host other researchers. “It helps keep that work going,” says Inouye. “It’s something that every taxpayer should be proud of…out of all the taxes they pay, a small fraction goes to the National Science Foundation. And then a small portion of that comes to Colorado, and a small portion of that comes to Gunnison County and to RMBL.”

For more information on RMBL, visit www.rmbl.org and to find the new publication, visit royalsocietypublishing.org/doi/full/10.1098/rspb.2022.2181.