Benjamin Jones UAF

PO Box 755860 FAIRBANKS AK 99775 United States

9074746794 bmjones3@alaska.edu https://orcid.org/0000-0002-1517-4711 Kenneth Tape kdtape@alaska.edu Jason Clark jaclark2@alaska.edu Ingmar Nitze ingmar.nitze@awi.de Guido Grosse guido.grosse@awi.de Jeff Disbrow disbr007@umn.edu Arctic landscapes are in a state of transition due to changes in climate occurring during both the summer and winter seasons. Scattered observations indicate that beavers (Castor canadensis) have moved from the forest into tundra areas during the last 20 years, likely in response to broader physical and ecosystem changes occurring in Arctic and Boreal regions. The implications of beaver inhabitation in the Arctic and Boreal are unique relative to other ecosystems due to the presence of permafrost and its vulnerability associated with beaver dams and inundation. Our study specifically examines the role of beavers in controlling surface water dynamics and related thermokarst development in low Arctic tundra regions. We mapped the number of beaver dams visible in sub-meter resolution satellite images acquired between 2002 and 2019 for a 100 square kilometer study area (12 years of imagery) near Kotzebue, Alaska and a 430 square kilometer study area (3 years of imagery) encompassing the entire northern Baldwin Peninsula, Alaska. We show that during the last two decades beaver-driven ecosystem engineering is responsible for the majority of surface water area changes and inferred thermokarst development in the study area. This has implications for interpreting surface water area changes and thermokarst dynamics in other Arctic and Boreal regions that may also result from beaver dam building activities. This geospatial dataset provides the location of beaver dams in a 430 square kilometer study area encompassing the entire northern Baldwin Peninsula, Alaska. The location of beaver dams were manually digitized using sub-meter resolution satellite imagery mosaics for the years 2010, 2013, and 2019. beavers beaver dams arctic tundra None This work is licensed under the Creative Commons Attribution 4.0 International License. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. 430 square kilometer region encompassing the northern Baldwin Peninsula, Alaska -162.658747 -161.963071 66.946810 66.688542 2010 2019 Benjamin Jones UAF

PO Box 755860 FAIRBANKS AK 99775 United States

9074746794 bmjones3@alaska.edu https://orcid.org/0000-0002-1517-4711 Beaver dams were mapped using high-resolution satellite imagery available from the DigitalGlobe Inc. imagery archive. The spatial resolution of the panchromatic imagery ranged from 40 centimeter to 70 centimeter and the frequent image acquisition dates provided an opportunity for cloud-free observations suitable for identifying beaver dams across the study period (2010-2019). The imagery was orthorectified using the 2 arc-second resolution U.S. Geologic Survey National Elevation Dataset (National Elevation Dataset, 2002) for Alaska and corrected to top-of-atmosphere reflectance to facilitate time series analysis. Beaver dam mapping positions were based on the orthorectification results from the 2019 image to account for subtle differences in image geolocation in prior years. Based on suitable and available imagery, the northern Baldwin Peninsula study region (430 square kilometer) was mapped each year in 2010, 2013, and 2019. Beaver dams were manually mapped in each image in both study areas at a scale of 1:1,000. All individual, apparently active dams were designated as a point feature in the GIS (geographic information system) database in each image. If a dam failed or was abandoned in a subsequent year it was not counted in the latter time series unless it was re-established. Benjamin Jones UAF principalInvestigator Kenneth Tape principalInvestigator Christopher Arp principalInvestigator NSF 1850578 Northern_Baldwin_Peninsula_Study_Area_Beaver_Dams_2010_2013_2019_gdb.zip Geospatial data on beaver dam locations in the northern Baldwin Peninsula region. CRS (Coordinate Reference Systems) is unprojected WGS84. The horizontal coordinate system name is GCS_WGS_1984 Northern_Baldwin_Peninsula_Study_Area_Beaver_Dams_2010_2013_2019_gdb.zip 54602 90dfc7c5cf9a1e23437cfebf604736d42d9d00e6 application/zip https://cn.dataone.org/cn/v2/resolve/urn:uuid:2b635336-0a55-44ab-868a-631e1b5746f7 OBJECTID Object identification Object identification Lat Latitude of the point in decimal degrees. degree real Long Longitude of the point in decimal degrees. degree real Point GCS_WGS_1984