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1. Swan Lake Creek Study Reach Datasets - beaver dams, flowlines, and UAS imagery; Seward Peninsula, Alaska; 2006-2021

   https://doi.org/10.18739/A2FJ29D9X  

   Jones, Benjamin; Tape, Ken; Clark, Jason; Bondurant, Allen; Ward Jones, Melissa; Gaglioti, Benjamin; Elder, Clayton; Witharana, Chandi; Miller, Charles (January 2021, NSF Arctic Data Center)

   Beavers have established themselves as a key component of low arctic ecosystems over the past several decades. The data presented here document the occurrence, reconstruct the timing, and highlight the effects of beaver activity on a small creek valley confined by ice-rich permafrost on the Seward Peninsula, Alaska. We analyzed very high resolution satellite imagery to digitize beaver dams and stream channels from the years 2006, 2011, 2014, 2015, 2017, 2019, 2020, and 2021. We also acquired Uncrewed Aircract System (UAS) imagery on 06 August 2021 and created a 5 centimeter (cm) resolution orthophoto mosaic and a 15 cm resolution digital surface model. Our data show that beaver engineering between 2006 and 2021 caused a systems-level response to a small tundra stream that promoted lateral expansion of the creek valley into an ice-rich permafrost hillslope and development of a diffuse network of stream channels expanding the area of potential beaver engineering in the future. The datasets support the findings presented in this accepted paper - Jones, B.M., K.D. Tape, J.A. Clark, A.C. Bondurant, M.K. Ward Jones, B.V. Gaglioti, C.D. Elder, C. Witharana, and C.E. Miller. Accepted. Multi-dimensional remote sensing analysis documents beaver-induced permafrost degradation, Seward Peninsula, Alaska. Remote Sensing. 

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2. Multi-Dimensional Remote Sensing Analysis Documents Beaver-Induced Permafrost Degradation, Seward Peninsula, Alaska

   https://doi.org/10.3390/rs13234863  

   Jones, Benjamin M.; Tape, Ken D.; Clark, Jason A.; Bondurant, Allen C.; Ward Jones, Melissa K.; Gaglioti, Benjamin V.; Elder, Clayton D.; Witharana, Chandi; Miller, Charles E. (December 2021, Remote Sensing)

   Beavers have established themselves as a key component of low arctic ecosystems over the past several decades. Beavers are widely recognized as ecosystem engineers, but their effects on permafrost-dominated landscapes in the Arctic remain unclear. In this study, we document the occurrence, reconstruct the timing, and highlight the effects of beaver activity on a small creek valley confined by ice-rich permafrost on the Seward Peninsula, Alaska using multi-dimensional remote sensing analysis of satellite (Landsat-8, Sentinel-2, Planet CubeSat, and DigitalGlobe Inc./MAXAR) and unmanned aircraft systems (UAS) imagery. Beaver activity along the study reach of Swan Lake Creek appeared between 2006 and 2011 with the construction of three dams. Between 2011 and 2017, beaver dam numbers increased, with the peak occurring in 2017 (n = 9). Between 2017 and 2019, the number of dams decreased (n = 6), while the average length of the dams increased from 20 to 33 m. Between 4 and 20 August 2019, following a nine-day period of record rainfall (>125 mm), the well-established dam system failed, triggering the formation of a beaver-induced permafrost degradation feature. During the decade of beaver occupation between 2011 and 2021, the creek valley widened from 33 to 180 m (~450% increase) and the length of the stream channel network increased from ~0.6 km to more than 1.9 km (220% increase) as a result of beaver engineering and beaver-induced permafrost degradation. Comparing vegetation (NDVI) and snow (NDSI) derived indices from Sentinel-2 time-series data acquired between 2017 and 2021 for the beaver-induced permafrost degradation feature and a nearby unaffected control site, showed that peak growing season NDVI was lowered by 23% and that it extended the length of the snow-cover period by 19 days following the permafrost disturbance. Our analysis of multi-dimensional remote sensing data highlights several unique aspects of beaver engineering impacts on ice-rich permafrost landscapes. Our detailed reconstruction of the beaver-induced permafrost degradation event may also prove useful for identifying degradation of ice-rich permafrost in optical time-series datasets across regional scales. Future field- and remote sensing-based observations of this site, and others like it, will provide valuable information for the NSF-funded Arctic Beaver Observation Network (A-BON) and the third phase of the NASA Arctic-Boreal Vulnerability Experiment (ABoVE) Field Campaign. 

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3. Ecophysical dynamics of beaver ponds in Arctic Alaska: Implications for permafrost, aquatic habitat, and water quality

   https://doi.org/10.1002/ecs2.70371  

   Glass, Thomas W; Tape, Ken D; Clark, Jason A; Johnston, Sarah Ellen; Jones, Benjamin M; Kehoe, Paige; Loranty, Michael M; Maio, Christopher V; Rangel, Rodrigo Correa; Zavoico, V Sebastian (September 2025, Ecosphere)

   Abstract Beavers (Castor canadensis) are rapidly colonizing the North American Arctic, transforming aquatic and riparian tundra ecosystems. Arctic tundra may respond differently than temperate regions to beaver engineering due to the presence of permafrost and the paucity of unfrozen water during winter. Here, we provide a detailed investigation of 11 beaver pond complexes across a climatic gradient in Arctic Alaska, addressing questions about the permafrost setting surrounding ponds, the influence of groundwater inputs on beaver colonization and resulting ponds, and the change in surface water and aquatic overwintering habitat. Using field measurements, in situ dataloggers, and remote sensing, we evaluate permafrost, water quality, pond ice phenology, and physical characteristics of impoundments, and place our findings in the context of pond age, local climate, permafrost setting, and the presence of perennial groundwater inputs. We show beavers are accelerating the effects of climate change by thawing permafrost adjacent to ponds and increasing liquid water during winter. Beavers often exploited perennial springs in discontinuous permafrost, and summertime water temperatures at spring‐fed (SF) beaver ponds were roughly 5°C lower than sites lacking springs (NS). Late winter liquid water was generally present at pond complexes, although liquid water below seasonal ice cover was shallow (5–82 cm at SF and 5–15 cm at NS ponds) and ice was thick (median: 85 cm). Water was less acidic at SF than NS sites and had higher specific conductance and more dissolved oxygen. We estimated 2.4 dams/km of stream at sites on the recently colonized (last ~10 years) Baldwin Peninsula and 7.4 dams/km on the Seward Peninsula, where beavers have been present longer (~20+ years) and groundwater‐surface water connectivity is more common. Our study highlights the importance of climatic and physiographic context, especially permafrost presence and groundwater inputs, in determining the characteristics of the Arctic beaver pond environment. As beavers continue their expansion into tundra regions, these characteristics will increasingly represent the future of aquatic and riparian Arctic ecosystems. 

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4. Permafrost thaw depth measurements at beaver pond locations in Northwestern Alaska, 2022-2026

   https://doi.org/10.18739/A2DN3ZX65  

   Tape, Ken; Glass, Thomas; Jones, Benjamin (January 2023, NSF Arctic Data Center)

   This dataset contains permafrost thaw depth measurements at Alaskan beaver ponds collected as part of the Arctic Beaver Observation Network and NSF ANS #1850578. The Arctic Beaver Observation Network is a 5-year project (2021-2026) funded by the National Science Foundation. The natural science part of the project uses remote sensing to observe the progress and impacts of beaver engineering in the Arctic, starting in Alaska and extending into Canada and Eurasia. The project also establishes field sites at tundra beaver ponds to study the implications of beaver engineering on hydrology and permafrost, as well as pond evolution documented using Unmanned Aerial Systems (UAS). Remote sensing work will map beaver ponds over time. Field measurements at tundra beaver ponds are made in August and late March. Data generated by field measurements include water level and temperature from pressure-transducers, subsurface imaging from ground-penetrating radar, sonar measurements for beaver pond bathymetry, tabular data associated with water quality measurements, and ice thickness and water depth (in winter). Data is also posted from UAS surveys: annual visible and multi-spectral surveys, as well as snow depth. This dataset comprises thaw depth measurements along transects near beaver ponds, to document permafrost impacts over time. 

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5. Increase in beaver dams controls surface water and thermokarst dynamics in an Arctic tundra region, Baldwin Peninsula, northwestern Alaska

   https://doi.org/10.1088/1748-9326/ab80f1  

   Jones, Benjamin M.; Tape, Ken D.; Clark, Jason A.; Nitze, Ingmar; Grosse, Guido; Disbrow, Jeff (June 2020, Environmental Research Letters)

   Abstract Beavers are starting to colonize low arctic tundra regions in Alaska and Canada, which has implications for surface water changes and ice-rich permafrost degradation. In this study, we assessed the spatial and temporal dynamics of beaver dam building in relation to surface water dynamics and thermokarst landforms using sub-meter resolution satellite imagery acquired between 2002 and 2019 for two tundra areas in northwestern Alaska. In a 100 km²study area near Kotzebue, the number of dams increased markedly from 2 to 98 between 2002 and 2019. In a 430 km²study area encompassing the entire northern Baldwin Peninsula, the number of dams increased from 94 to 409 between 2010 and 2019, indicating a regional trend. Correlating data on beaver dam numbers with surface water area mapped for 12 individual years between 2002 and 2019 for the Kotzebue study area showed a significant positive correlation (R²= 0.61; p < .003). Beaver-influenced waterbodies accounted for two-thirds of the 8.3% increase in total surface water area in the Kotzebue study area during the 17 year period. Beavers specifically targeted thermokarst landforms in their dam building activities. Flooding of drained thermokarst lake basins accounted for 68% of beaver-influenced surface water increases, damming of lake outlets accounted for 26%, and damming of beaded streams accounted for 6%. Surface water increases resulting from beaver dam building likely exacerbated permafrost degradation in the region, but dam failure also factored into the drainage of several thermokarst lakes in the northern Baldwin Peninsula study region, which could promote local permafrost aggradation in freshly exposed lake sediments. Our findings highlight that beaver-driven ecosystem engineering must be carefully considered when accounting for changes occurring in some permafrost regions, and in particular, regional surface water dynamics in low Arctic and Boreal landscapes. 

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