
By Kathleen Wong, UC Natural Reserve System
California’s spring meadows are a treat to the senses. Stands of wildflowers in every hue, from flaming California poppies, to pink checker mallow, to crimson Indian paintbrush, waft come-hither scents across emerald fields. Bees and butterflies hungry for nectar and pollen find these come-hither cues irresistible.
Those pollinators have long included the western bumblebee. Tubby and clad in yellow and black fuzz, Bombus occidentalis was once the most common bumblebee on the West Coast. But over the past 30 years, populations of this important pollinator have cratered. The insect is now a candidate for the federal Endangered Species List.
Scientists are still puzzling over the cause. Some believe a fungal parasite known to parastize bumble bee colonies is the culprit. Others have suggested agriculture and development have crowded wildflowers the bees need to survive.
UC Berkeley Anna Hatzakis plans to devote her summer to the case. “I’m trying to see if patterns exist where declines in those floral species match declines in Bombus occidentalis,” Hatzakis says. “I have a feeling there will be a pretty solid correlation between the two.”

Hatzakis will be able to conduct her research full time thanks to support from a UC Natural Reserve System Field Science Fellowship. She will receive guidance from her fellowship mentors, UC Berkeley Professor of Integrative Biology Michael Boots and his graduate student, Nina Sokolov. The fellowship will not only provide her a stipend, but also enable her to stay at the NRS’s Sagehen Creek Field Station near Truckee to do her field work.
“Sagehen is one of the only sites in the state where we’re finding Bombus occidentalis, and to travel back and forth from Berkeley for weeks at a time would be a challenge.”
At Sagehen, Hatzakis hopes to observe which flowers the bumblebee prefers to visit, and possibly gather pollen grains stuck to their bodies to obtain a more complete picture of its foraging preferences. She is already compiling a list of local flowers complete with images of their pollen to prepare. Eventually, Hatzakis will compare what she collects to pollen on specimen bumblebees in museums.
Hatzakis and her advisers are among three UC undergraduates and their faculty partners who were awarded Field Science Fellowships in 2023. The fellowship is designed to enable undergraduates, especially those from underrepresented backgrounds in the field sciences, to undertake full time field research, while also encouraging them the development of mentoring relationships critical to professional success. Each team will receive $5,000 for the undergraduate and $1,000 for project costs.
Launched in 2020, the NRS Field Science Fellowships are funded by the Samuelsen Conservation Scholars Initiative, which supports NRS diversity and inclusion efforts. The initiative honors the first director of the NRS, J. Roger Samuelsen.
Without the Field Science Fellowship, Hatzakis says she would normally spend her summer juggling multiple jobs. A first-generation re-entry student, she has worked since age 14 as a freelance artist, a nanny, retail clerk, and even a farm hand.
The fact that Hatzakis is majoring in both integrative biology and conservation and resources at Berkeley is particularly remarkable given her background. Homeschooled since she was a child, her lessons never included chemistry, physics, or key foundational concepts of biology. In community college, she initially struggled to overcome these educational gaps.
These challenges have made Hatzakis particularly appreciative of the fellowship. “I cannot express how excited I am to be able to devote my entire summer to this project and not have anything else on my plate that’s too pressing,” she says.

How a hybrid becomes a new species
UC Riverside undergraduate Danielle Marcelin-Stone will also use her Field Science Fellowship to observe flowers and pollinators. But Marcelin-Stone plans to zero in on the flowers, not the bees. The biology major will decipher how two species of wild Penstemon have managed to produce a hybrid third species with guidance from her fellowship mentor, UC Riverside Professor Kate Ostevik.
Over spring, Marcelin-Stone propagated the two parental species plus their hybrid in a campus greenhouse. She’ll plant them at the NRS’s Box Springs Reserve, located on a peak behind campus.
“It’s really important for us to use Box Springs because they have the perfect environment factors that will benefit our plants that are native to California. Box Springs is also close to our facilities in Riverside which will make transporting plants easier and reduce the risk of damage,” Marcelin-Stone says.

Once the plants are in their native habitat, she’ll observe how the hybrid manages to stay reproductively isolated from its parents—the prerequisite for becoming its own species. She’ll note whether it flowers at a different time of day from its parents and whether it is visited by different pollinators. She’ll also create her own hybrid from scratch, dusting pollen from one to the other by hand. She’ll know the cross is successful if the “mother” of the two parent plants produces a fair amount of seeds.
Raised in a low-income household, by a mother who has long battled breast cancer, Marcelin-Stone hasn’t let life’s hurdles slow her down. Indeed, her mother’s diagnosis is what led to her interest in genetics.
“I think I was 11 when I was in the genetic counselor’s office where he was explaining things what it means to have the breast cancer or BRCA gene, and what kinds of factors could have possibly created such a mutation. It made me want to learn more about it coming into college,” she says.
Receiving the Field Science Fellowship, Marcelin-Stone says, is a vote of confidence in her future. “You have so many obstacles as a person of color. People don’t think that you can achieve much. But this fellowship shows me that I can keep achieving until I reach my ultimate goal.”

The fate of plankton after poison
Rather than spending her time in meadows, UC Irvine undergraduate Soffia Ramsey will be immersing herself in high elevation lakes. The food web in many of the Sierra’s naturally fishless lakes has been upended by the introduction of trout. The fish devour zooplankton that normally keep algae under control. This can cause limpid lake waters to turn murky green.
Sequoia and Kings Canyon National Parks want to control the fish with a poison called Rotenone. The worry is that the treatment will harm the very plankton it is supposed to restore.
Ramsey’s mentor, UC Irvine Professor Celia Symons, has been monitoring the abundance and types of plankton in three park lakes for the past six years. One has always been fishless, one is in transition, and the third will eventually be treated with Rotenone.
“We’re basically going to be taking samples from the water column and monitoring the abundance of the zooplankton communities. Once the Rotenone is added, then we can document the effects of the treatment,” Ramsey says. While out on the water, she’ll also pull sediment cores from the bottom of each lake.

Ramsey will accompany the Symons lab to the NRS’s Sierra Nevada Aquatic Research Laboratory in Mammoth Lakes this summer. Located near Ramsey’s study lakes, the lab also has facilities enabling her to identify and count plankton in the samples, and potentially conduct additional experiments in tanks.
Ramsey has been shoring up her plankton identification skills since she started volunteering with the lab this winter. She’s also been ensuring she can do the tasks she’s asked to perform at those high-elevation field sites. “I actually started running and hiking more this quarter to prepare,” Ramsey says.
The fellowship project will be very different from Ramsey’s previous summer jobs. “The past internships that I’ve held, they’ve all been remote work on the communication side of science. This time I actually get to go out there and get my hands dirty.”
Currently in her third year of college, Ramsey suspects this summer of field work will help guide her future. “I think this experience is going to be a deciding factor in what I do after graduation.”
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