Part of the UC Davis Natural Reserve System (NRS), Stebbins Cold Canyon Reserve is set in a steep inland canyon of the California Inner Coast Range, just west of Winters, California. The reserve is one of only two or three UC Davis field stations open to public recreation, and its trails are the first I visited after moving to California in 2019. I remember being struck that spring by the Barney-like green of the Vaca Mountains, which looked fantastical from a distance and were a sharp contrast to the agricultural flatlands of Davis and Winters. Stebbins burned in 2020 as the Lightning Complex Fires tore through the area, and I’ve returned to the canyon often since then to watch it recover. 

A year ago, when I started working at the Institute of the Environment, I heard a cheerful voice with a distinct South African accent down the hall from my office. I was delighted to learn the speaker was Paul Havemann, manager of Stebbins Cold Canyon Reserve. I’ve been curious about Stebbins’ unique identity among the wider network of the UC Natural Reserve System. When my colleagues and I saw haunting photos of Stebbins covered in snow earlier this year and wanted to share them more widely, we decided that was as good an excuse as any to interview Paul about the reserve:

How long have you been managing Stebbins, and what were you doing prior to joining UC Davis to be part of the NRS team?

I started as a steward working at Quail Ridge, Stebbins, and Jepson Prairie natural reserves in April 2013. The four years prior to that were spent settling into my new life in the U.S.

During the first year, I worked as a seasonal worker for the Nevada Department of Agriculture’s Entomology Department. I spent the summer of 2009 traversing every far-flung corner of Nevada collecting samples of insects and sometimes undertaking other dubious activities such as Mormon cricket control. Winter was spent sorting and pinning specimens in the lab.

A somewhat enjoyable first year in the U.S., we lived on the outskirts of Reno in the eastern Sierra foothills, which was nice! We moved to Davis in 2010, when my wife started working at the U.S. Fish and Wildlife Service’s Pacific Southwest Research Headquarters, and I became blissfully unemployed for the next three years as a stay-at-home dad. During that time, I finished up my master’s degree.

Prior to coming to the U.S., I managed a section of the Isimangaliso Wetland Park World Heritage site in South Africa for three years, and prior to that I was an assistant manager of the Hluhluwe-iMfolozi Park for 16 years. I worked for the conservation agency Ezemvelo KZN Wildlife for most of my post-school years, did three years in the private game farming industry, and spent a year with the South African National Parks as an intern following completion of my national service, which was in the navy.

Last year, NRS acquired nearly 500 acres of oak woodlands and chaparral communities from the Land Trust of Napa County to incorporate into the Stebbins Cold Canyon Reserve. How does your job change when you have 500 more acres to steward?

The main changes include taking responsibility for monitoring what transpires on the new acreage, the maintenance of a couple of miles of backcountry road, and the responsibility to be the NRS conduit to one private landowner. The changes are immensely exciting from an ecological standpoint, as the new Spencer property has created a contiguous link to Quail Ridge, which elevates the significance the NRS has in guiding conservation practices in the area. It provides new opportunities for Stebbins to up its research ante because it has vehicular access and could impact our understanding of what the benefits of having a low-use buffer around a heavily used public trails area might be for the reserve. Although not necessarily unique, it is a beautiful, wild, and uniquely biodiverse addition to the NRS inventory.

Can you share some examples of research conducted at Stebbins?

For the most part, we host more survey-type work and classes than the conventional field station-type access we are used to at other reserves, like Quail Ridge, next door.

For example, we have recently collaborated with large groups of UC Davis restoration ecology students on some pretty neat “minimum tool” water infiltration methods and structures along the trails. I would love to see more focus on using these opportunities to increase our knowledge about backcountry restoration.

For another project, we’ve set up several motion-sensor cameras to capture wildlife in the area during the day and night. The Stebbins Camera Trap program forms part of the reserve's citizen science initiative with Davis High School to monitor local biodiversity. We’ll use data from this project to determine the frequency and spatial distribution of the species found in the photos and track changes in animal presence as the landscape recovers from the fires that ravaged it in August 2020. We are working on a vision for Stebbins that embraces the citizen science community and students of every discipline to promote research and democratize the collection of environmental monitoring data. We could have an entire conversation about that work alone.

Stebbins is unique in that it’s a field station that’s also open to public recreation. Does this create challenges for research?

At Stebbins, we battle to meet our research mission because of the enormous public aspect of use out there and the fact that it is generally not very conducive to research. And with Quail Ridge just over the valley, with everything and more to offer researchers, it is all the harder to sell Stebbins as a great space for research. However, with a uniqueness leaning toward the social sciences, a heavily used ecological resource like Stebbins has the potential to expand conventional (wildlands) natural science interests to combine the social-ecological impacts and benefits that transpire there.

What’s the untapped potential of Stebbins as a field station? What are some of your goals for the reserve?

The untapped potential for Stebbins is two-fold: 

1. Focus on meeting more of our primary NRS mission to facilitate research. Our openness to public users offers tremendous opportunities to facilitate a citizen science program and to expand conventional wildlands research disciplines to include the social sciences. This is the main purpose of the docent program which was created to engage the public, UC Davis, and K-12 students in establishing more environmental monitoring projects. We’d like to engage the UC Davis community even more.
2. Promote research areas specific to Stebbins, including:
   • Minimum tool restoration and remediation methods and effectiveness for Stebbins’ trails system. Stebbins is unique in that everything that gets done there is done in the absence of any motorized assistance. Conventional restoration methods, for example, assume that the replanting of a disturbed area will be facilitated through the use of irrigation systems that will improve the chances of plant starts surviving beyond an establishment period. At Stebbins, our vision of restoration practices and approaches does not include water availability, and we therefore do not practice conventional restoration because of it. We focus rather on facilitating the ecological regeneration of a site through the application of “minimum tool” practices, such as the harvesting of local materials onsite to build water traps and infiltration structures that will speed up the regeneration process.
   • We potentially have a grad student who will be doing a project based on a reestablishment methodology they call “seed bombing.” The concept of seed-bombing was pitched to me as a potential remediation tool for Stebbins that would give us the added opportunity of plant reestablishment that does not require conventional irrigation methods associated with plant starts. Hypothetically, materials for Stebbins seed balls (clay, dirt and seeds) would be sourced within the locality of a given restoration site, shaped into a seed ball, dried, and carried to site where they are inserted into a regeneration sites’ sediment trap zone. There is a minefield of protocol that we would need to have in place to do this, but in principle, this opens a new door on improving our capacity for effective backcountry restoration.
   • Promote opportunities for research-with-motorized-access to both the new Spencer Ranch property and the Cahill Riparian Reserve to the east of Stebbins.
   • Developing a model for the remote monitoring of mammals, birds, and bats in off-the-grid settings. 

For more information about Stebbins Cold Canyon, please visit the reserve’s webpage. You can also sign up for educational walks at Stebbins, which cover topics like the history of California newts and wilderness photography here.

Jullianne Ballou is the associate director of strategic initiatives at the Institute of the Environment.