Pronghorn & Solar Development: The Case for Peer Review

Solar energy is expanding fast across the American West, and our understanding of how it affects wildlife hasn’t kept pace.

Pronghorn are one of the most iconic and ecologically significant species in the landscape and have become a key to understanding how large animals respond to utility-scale solar development. Researchers hypothesized that if pronghorn were adverse to solar facilities, they would see a long-term trend of avoidance of areas near active facilities, but so far, the data indicate otherwise. Below, Aaron Facka and Kevin Smith dig into what their research is showing, the important role of peer review in sharing findings in a new field, and what questions are still waiting to be answered.

Can you tell us a bit about the research so far?

Kevin Smith: During the first three years of our project, we have been busy collecting heaps of data to help us understand the impacts of solar development on pronghorn and other wildlife.  Our project has two major field components: GPS collars deployed on pronghorn to track their locations and movements, and a suite of non-invasive surveys to track other wildlife and give us information on uncollared pronghorn. We now have over two full years of data with both data types. That equates to over 5 million trail cam photos, 1 million GPS locations, and thousands of tracks, sign, and visual records recorded!  Overall, it’s a staggering amount of data, but, of itself, data provides limited value. I once read a sign hung proudly on a professor’s door that read ‘science is not finished until it’s communicated’. The first major step in communicating scientific endeavors is to subject them to peer-review and to, hopefully, have them published.

This project is one of the first of its kind to study how solar development affects pronghorn and other wildlife at an active facility. Why does that make the peer-review process especially important here?

Aaron Facka: For many the concept of peer-review publication may seem like a highbrow endeavor that is intended only for other researchers – far removed from the on-the-ground realities of solar development. Some may even question if such publications are needed because the data collected should tell the real story. It’s true that the data, our observations, provide the core of our inference, the knowledge we gain, and the decisions we make with that newfound knowledge.

“I once read a sign hung proudly on a professor’s door that read ‘science is not finished until it’s communicated’. The first major step in communicating scientific endeavors is to subject them to peer-review and to, hopefully, have them published.”

Yet, data that is poorly collected, analyzed in inappropriate ways, or that is attributable to false mechanisms can be more dangerous than not having collected data at all. The peer-review process is one step that helps to minimize bias and to weed out poor research design and analysis. More than that, peer-reviewed work should document the entire research process, making it accessible and transparent.  Effectively, good science should not just demonstrate what you know but also how you know it. This process, ideally, makes knowledge repeatable, replicable, and ultimately reliable.

Kevin Smith:  Because research on wildlife-solar interactions is still nascent, our methods and observations need the highest degree of scrutiny we can subject them to. Poorly collected or analyzed data can be easily skewed to reflect our own biases and these biases can then be transmitted to recommendations or practices at other sites or situations. Observations made at one location may be inconsistent with those at another because of differences in methods or underlying conditions and such errors are more likely when our work is not subjected to critical review. Consequently, we view peer-reviewed papers as the first step in communicating our research and the foundation for developing robust recommendations that incorporate wildlife into solar siting and design.

Walk us through what the research is working toward and where things stand now.

AF: One goal of our research is to identify and minimize the impacts of USSE facilities on wildlife through proper siting and to develop mitigation strategies that can be used by developers, land managers, wildlife agencies, and regulators. Our first research priority was to quantify, using GPS collars, how pronghorn used the areas near solar construction during and after it was built. In collaboration with Conservation Science Partners, we have used the first 1.5 years of data to evaluate the numbers and frequency of pronghorn in relation to San Juan Solar in northwestern New Mexico to evaluate its potential impact on space-use, resource selection, movement, and behavior during both the construction and post-construction periods.

We hypothesized that pronghorn would preferentially select areas farther from the facility, that high-use habitat closest to the solar facility would decline over time, and that pronghorn would show different behaviors in areas closer to the facility than further away if they perceive it as a risk. To accomplish this, we developed resource selection functions that help us to predict locations that pronghorn are likely to select, irrespective of solar. This information provides a baseline for comparison and one way to evaluate the effects of solar. This manuscript has been submitted and is currently under peer review in the Journal Ecosphere. This paper provides the first layers of knowledge about pronghorn and their patterns, but it is only one level of information meant to set the table for other work.

KS: Our second manuscript will focus on pronghorns’ use of inter-array passages.  As we described in a previous post, passages between individually fenced solar arrays are thought to facilitate movement through facility footprints, but this has remained largely untested.  San Juan Solar has nine individually fenced arrays and one battery storage facility, and our data suggests all of the passages between arrays have been used to varying degrees by pronghorn.  This manuscript will examine factors such as passage size relative to use, allowing a better understanding of what pronghorn are more likely to move through or use. This information may be critical for the design of projects at new sites, and puts additional emphasis on the need to site projects such that they minimize obstruction of existing connectivity. This paper is in its early stages, and we hope to be able to submit it later in 2026.

AF: A secondary objective for this project is to help test and develop tools that allow wildlife managers, developers, or tribes to assess wildlife and the effects of solar without having to collar animals. In our project development, we specifically identified noninvasive methods that could provide similar types of information as our GPS collars without the higher cost. Noninvasive methods also have the advantage of the ability to detect and monitor multiple species at the same time.

KS: Thus far we have only just begun to evaluate patterns of use and change in use for pronghorn using these methods, which we can compare to our GPS data, but we are also beginning to quantify rates of use for other common mammals.  In the fall of 2025, we attended the Renewable Energy Wildlife Institute’s Solar Wildlife & Ecosystems Research meeting, where we presented a paper on such an analysis. This analysis has led to a thirdmanuscript where we will examine these non-invasive survey data, comparing the effectiveness of different survey methods, the effort required to achieve comparable results, and their relative costs. This paper will provide a strong foundation for how to provide recommendations on how to survey for wildlife before siting and how to monitor once a project has been designed.

You’re sitting on a substantial dataset. What feels most unresolved, and where do you see this research needing to go?

AF: We could probably make a list of dozens of potential papers and avenues of research to explore with our existing data. For example, we have yet to fully use all our data from our Southern Project Area, where we expected solar to be developed.  Even without a solar facility, research done in this area is an important comparison point that helps us to quantify patterns of use and changes in use that have nothing to do with solar. New solar facilities are being built where we have existing data from all research.

This is to say nothing of research dealing with other species we have documented with all our noninvasive surveys, sub-replication within sampling units, optimal setup for noninvasive surveys relative to critical times of year or to existing terrain or trails, or how proximity of solar to other terrain or human features affect movements or behaviors of animals. Not all ideas become papers, and some ideas simply become parts of larger topics. In part, these decisions are shaped by the process of review, revision, and resubmission.

Ultimately, even these are only one component of sharing our research and trying to have wildlife be more directly considered as we humans develop new ways of producing energy.