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Beaver dams are gaining popularity as a low-tech, low-cost strategy to build climate resiliency at the landscape scale. They slow and store water that can be accessed by riparian vegetation during dry periods, effectively protecting riparian ecosystems from droughts. Whether or not this protection extends to wildfire has been discussed anecdotally but has not been examined in a scientific context. We used remotely sensed Normalized Difference Vegetation Index (NDVI) data to compare riparian vegetation greenness in areas with and without beaver damming during wildfire. We include data from five large wildfires of varying burn severity and dominant landcover settings in the western United States in our analysis. We found that beaver-dammed riparian corridors are relatively unaffected by wildfire when compared to similar riparian corridors without beaver damming. On average, the decrease in NDVI during fire in areas without beaver is 3.05 times as large as it is in areas with beaver. However, plant greenness rebounded in the year after wildfire regardless of beaver activity. Thus, we conclude that, while beaver activity does not necessarily play a role in riparian vegetation post-fire resilience, it does play a significant role in riparian vegetation fire resistance and refugia creation.

North American beavers ( Castor canadensis ) build dams and ponds that alter streamflow, enhance floodplain water storage, and provide refugia during droughts and wildfires. However, drivers of pond area variability remain poorly understood. Here, we quantified the influencing factors that drive pond area and dam length variations using an explanatory modeling approach, after mapping surface water area of beaver ponds and creating beaver pond complexes. Mapped area correlated well with manual delineations (r 2  = 0.89), and additive pond area and dam length across 87 complexes followed a significant log-log scaling relationship. Dam length was the strongest covariate of pond area, while woody vegetation height and stream power index were also influential; together, these covariates explained 74% of the variation. Our results provide an empirical foundation to inform site selection and prioritization for beaver restoration, supporting watershed management, climate resilience and ecological conservation strategies in regions with comparable data availability and landscape characteristics. Dam length, woody vegetation height, and stream power index explain 74% of the variation in pond area, providing a foundation for beaver restoration and watershed management in the western US, according to a modeling approach after mapping surface water area of beaver ponds and creating beaver pond complexes.

Beaver‐based restoration is emerging as a cost‐effective conservation and climate adaptation strategy, but efforts are constrained by limited knowledge of pre‐colonial beaver distribution and their long‐term ecosystem impacts. Here, we apply sedimentary ancient DNA (sedaDNA) techniques to investigate the history of beaver occupancy at three lakes in Grand Teton National Park, Wyoming, over the last ~10,000 years, as well as interactions with the local plant community. We document a dynamic history of beaver presence in two subalpine lakes (Taggart and Jenny Lakes) and demonstrate no history of beaver occupancy at the higher elevation alpine lake (Lake Solitude). Beavers were first detected at Jenny Lake around 7200 years BP and intermittently thereafter. At nearby Taggart Lake, beavers were first detected at ~5900 years BP and continuously from 5200 years BP onward. Vegetation metabarcoding revealed a shift in plant community coinciding with beaver establishment in these two subalpine lakes, as well as an increase in taxonomic diversity. These changes coincide with regional trends toward wetter conditions. Notably, beavers persist at Taggart Lake during inferred droughts, indicating a potential role in maintaining wetlands through extended periods of climatic stress. Our results demonstrate sedaDNA as a powerful, novel technique for reconstructing robust time series data of historical beaver occupancy dynamics.

As climate changes and global temperatures rise, we are faced with unique new challenges to our land, ecosystems, livelihood, and infrastructure. One way of dealing with the impacts of climate change is to build climate resiliency - or the ability to resist or recover from climate change-driven disturbances. This dissertation explores two avenues for building climate resiliency in a warming world. Chapters 2 and 3 focus on the physical earth and creating resilient landscapes through the natural impacts of beaver damming. Chapter 4 focuses on building a more diverse geoscience workforce to creatively tackle the challenges presented by climate change. In Chapter 2 I investigate one potential consequence of beaver-related water storage in the landscape - drought buffering. Using remotely sensed Normalized Difference Vegetation Index (NDVI) and modeled evapotranspiration (ET) data, I compare riparian areas with beaver to riparian areas without beaver on two creeks in semi-arid Nevada during both seasonal and multiyear droughts. The beaver-dammed riparian areas had ET and NDVI signatures more similar to that of irrigated cropland than to riparian areas without beaver. This suggests that the drought-buffering is likely stemming from the unique storage and distribution of water in beaver-dammed landscapes. In Chapter 3 I push the bounds of beaver-driven climate resiliency determine whether or not beaver wetlands are uniquely resistant to wildfire. To do this, I use remotely sensed NDVI data to quantify the riparian vegetation response during five large wildfires along creeks that have variable amounts of beaver damming. Through comparison of NDVI before, during, and after fire in riparian areas with beaver damming to riparian areas without beaver damming, I show that beaver-dammed riparian areas are uniquely resistant to wildfire. In Chapter 4 I explore a different approach to building climate resiliency and focuses on the people solving climate issues, not the impacts of climate change on the physical earth. My research establishes that even infrequent training on accessibility and inclusivity can measurably change undergraduates' feelings of inclusion and connection to their academic department. That inclusion and connection is an integral component of retaining these students throughout their undergraduate careers.

People with disabilities are chronically underrepresented in many geoscience departments across the country. There are a number of proposed reasons why this underrepresentation persists, one of which is lack of instructor training in designing accessible curriculum and making high-quality accommodations. This not only puts students with accessibility needs at a disadvantage academically but also creates an unwelcoming environment. We determined through a broad survey of the instructors and undergraduate students that the geology department at a large research-focused university lacked sufficient instructor training on accessibility-related topics. We designed and implemented a scenario-based training at the university department scale to begin correcting the lack of training. Our training was designed for and given to teaching assistants (TAs), and we assessed the effectiveness of our training by measuring TA knowledge gain and retention throughout the fall 2017 semester; comparing the number of students approaching TAs with accessibility needs in the training year to years prior to the training; and gauging undergraduate feelings of inclusion throughout semester via a series of minute-paper style surveys. Our results show an increased baseline understanding of universal design and semester-long retention of that knowledge. The number of students approaching TAs with accessibility needs increased compared to years prior to the training, and undergraduates reported overall feeling that their TAs had a genuine interest in their learning as individuals. We conclude that our results merit the inclusion of an accessibility focused TA training in the annual training schedule.

Beaver-based restoration is emerging as a cost-effective conservation and climate adaptation strategy, but efforts are constrained by limited knowledge of pre-colonial beaver distribution and their long-term ecosystem impacts. Here, we apply sedimentary ancient DNA (sedaDNA) techniques to investigate the history of beaver occupancy at three lakes in Grand Teton National Park, Wyoming over the last ∼10 ka, as well as interactions with the local plant community. We documented a dynamic history of beaver presence in two sub-alpine lakes (Taggart and Jenny Lakes) and demonstrate no history of beaver occupancy at the higher-elevation alpine lake (Lake Solitude). Beavers were first detected at Jenny Lake around 7.2 ka and intermittently thereafter. At nearby Taggart Lake, beavers were first detected at ∼5.9 ka and continuously from 5.2 ka onwards. Vegetation metabarcoding revealed a shift in plant community coinciding with beaver establishment in these two sub-alpine lakes, as well as an increase in taxonomic diversity. These changes coincide with regional trends towards wetter conditions. Notably, beavers persist at Taggart Lake during inferred droughts, indicating a potential role in maintaining wetlands through extended periods of climatic stress. Our results demonstrate sedaDNA as a powerful, novel technique for reconstructing past beaver occupancy dynamics.

Beavers are famous for building extensive damming complexes1, which can extend over kilometer-scale distances2 and persist for centuries3. Dams have major impacts on their surrounding environment, including effects on the hydrology, geomorphology, and ecosystems of the area4. Current understanding of how the environment in turn affects beavers’ building activity centers on the single auditory cue of running water, based primarily on captive studies14,15. Observational challenges have limited a more detailed picture of the full feedback loop between beavers and their environment. Here we describe the detailed progress of new construction by 20 beaver colonies in northwest Montana, through field studies using drones to obtain surveys with spatial and temporal resolution each three orders of magnitude finer than typically reported5-13. We show that both the timing and location of beaver construction activity are influenced by environmental factors. Initiation of trail clearing, a stage preceding dam building, was associated with a narrow range of stream flow rates. Beavers preferentially built in locations associated with preexisting canals. These results emphasize the importance of non-dam elements in the beavers’ construction and its coordination across the colony, and point to environmental feedback processes that may span across years and unrelated colonies.