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Aerial surveys were conducted during 1983–2006 in the Ketchikan, Sitka, Kodiak, and Bristol Bay areas of Alaska to estimate trends in abundance of harbor seals.

The Bureau of Ocean Energy Management (BOEM), formerly the Minerals Management Service (MMS), and its precursor, the Bureau of Land Management, funded aerial surveys in the Beaufort, Chukchi, and Bering seas from 1979 to 2019. In 2008, through an Interagency Agreement between MMS and the Alaska Fisheries Science Center (AFSC, National Marine Fisheries Service, National Oceanic and Atmospheric Administration [NOAA]), the Marine Mammal Laboratory (MML, a division of AFSC), formerly the National Marine Mammal Laboratory assumed co-management responsibilities for these surveys. Throughout the history of the surveys, they were referred to as the Bowhead Whale Aerial Survey Project (BWASP) and the Chukchi Offshore Monitoring in Drilling Area (COMIDA) marine mammal aerial surveys, both of which are described in more detail below. In 2011, a new Interagency Agreement between BOEM and NMML was established to authorize NMML to continue the BWASP and COMIDA studies under the auspices of a single study, Aerial Surveys of Arctic Marine Mammals (ASAMM). In 2020 and 2021, aerial line-transect surveys for bowhead whales and other marine mammals were funded and co-managed by the North Slope Borough (NSB) through contract 2021-069 with the Cooperative Institute for Climate, Ocean, and Ecosystem Studies (CICOES), a part of the University of Washington, with collaboration from AFSC, NOAA Fisheries. Consistent survey protocol has been in effect on surveys conducted since 1982. Data collected from 1979 to 1981 were not vetted as carefully as data from 1982 to 2021, and should generally not be used for most analyses. WESTERN BEAUFORT SEA Aerial surveys in the western Beaufort Sea (south of 72 degrees N, 140-157 degrees W) have been conducted each year since 1979. MMS personnel and contractors conducted the surveys from 1979 to 2007. From 2008 to 2019, the surveys were conducted by MML. In 2020 and 2021, surveys were conducted by NSB. The primary goal of the project, also known as BWASP through 2010, ASAMM from 2011 to 2019, and NSB Autumn Aerial Surveys in 2020 and 2021, was to document bowhead whales (Balaena mysticetus) during their fall migration through the western Beaufort Sea, although data were also collected for all other marine mammals that were sighted during the surveys. The surveys were typically conducted during the months of September and October, when offshore drilling and geophysical exploration were feasible and when the fall subsistence hunt for bowhead whales takes place near Kaktovik, Cross Island (village of Nuiqsut), and Utqiagvik (formerly Barrow), Alaska. Additional surveys were conducted in the western Beaufort Sea during spring and summer 1979-1986, during summer 2011-2019, and from approximately 15 September to 15 October in 2020 and 2021. The emphasis of surveys in the Beaufort Sea was to conduct broad-scale surveys to assess shifts in the migration pathway of bowhead whales, and to coordinate effort and manage data necessary to support seasonal offshore drilling and seismic exploration regulations. The selection of survey blocks to be flown on a given day was nonrandom, based primarily on criteria such as observed and predicted weather conditions over the study area and offshore oil industry activities. From 2016 to 2019, to incorporate the area near Liberty prospect, all transects in survey block 1 were extended inshore of the barrier islands to the shoreline. From 19 July through 20 August 2016, transects extended north beyond the usual BWASP study area into study blocks 8, 9, and 10, and north of blocks 11 and 12 (beyond 72 degrees N) to survey Eastern Chukchi Sea (ECS) beluga habitat. In 2017, a coastal transect 1 km offshore between Point Barrow and Demarcation Bay in the Beaufort Sea was added. Otherwise, the project attempted to distribute effort evenly east-to-west across the entire study area. Aerial coverage favored inshore survey blocks because bowhead whales were rarely sighted north of blocks 2, 6, and 7

These data were used by Kuhn et al. (2015) to investigate how conclusions about predator-prey relationships change with increasing temporal disparity between predator tracking periods and prey surveys. Northern fur seals (n = 20) from St. Paul Island (Alaska, USA) were equipped with satellite tracking transmitters and time-depth recorders from July to October 2006. Fur seal dive and movement metrics were examined in relation to the relative abundance of the fur seals’ primary prey, walleye pollock (Gadus chalcogrammus), reported from the annual eastern Bering Sea groundfish survey. Relationships between foraging behavior metrics and prey abundance were examined within the Bering shelf survey grid cells at three time scales: within 2 weeks of the prey survey, within 1 month, and over the northern fur seal reproductive season (>4 months).

Floating glacial ice serves as a haul-out substrate for a significant number (10-15%) of Alaskan harbor seals, and thus surveying tidewater glacial fjords is an important component of statewide efforts to estimate seal abundance. Surveys conducted during pupping suggest that glacial haul outs have higher than average productivity and thus may serve as important source populations statewide. The availability of ice for hauling out varies with seasonal glacial dynamics, but over decades of climate change most tidewater glaciers are now retreating toward eventual grounding with many already ceasing to calve ice into the water. Compounding glacial retreat and thinning is the trend at most of these sites toward increasing tourism and a low compliance of tour vessels to seal approach guidelines and regulations. It is thus important to track glacial populations over the long-term especially as various impacts may degrade seal habitat leading to fewer glacial seals and potential impacts to the population state-wide. There are currently 28 glacial sites that have at least one actively calving tidewater glacier and in turn seals that haul out on the ice during the seals’ molting period, when most surveys have occurred. Due to concerns about vessel disturbance, Disenchantment and Icy Bays have been surveyed during molting almost annually between 2001-2011 (ex 2003); surveys occurred during pupping and molting in 2004 and 2005, and have occurred just during molting apx. every other year since 2011. Johns Hopkins Inlet in Glacier Bay has been surveyed annually using these methods since 2007, with surveys occurring during both pupping and molting. The remaining 25 sites have been surveyed on an opportunistic schedule (based on weather and aircraft availability), which for most sites equates to about every 2-3 years. Some of the smallest sites have been surveyed on a 4-5 year schedule. These schedules will likely continue with more abundant sites in Prince William Sound (e.g., College Fjord and Columbia) and Southeast Alaska (Tracy Arm, Endicott Arm, LeConte Bay, and Glacier Bay) having higher priority and contingent on management concerns.

This dataset supports efforts to estimate the abundance and trends in population size of Alaska harbor seals. Annual surveys of harbor seal populations are fundamental to estimation of seal abundance, distribution, and trends, which in turn are essential for stock assessment, conservation, and management. The most feasible approach to determining harbor seal distribution and abundance is to use aircraft to count seals when they haul out of the water and are visible. Harbor seals in Alaska occupy a geographically extensive range from approximately long. 172ºE to 130ºW (over 3,500 km east to west) and from lat. 51ºN to 61.5ºN (over 1,000 km north to south). Estimation of the abundance of harbor seals statewide requires broad-scale aerial surveys and these surveys have been conducted by NOAA Fisheries, the Alaska Department of Fish and Game, and other collaborators since the early 1980s. This dataset reflects counts of harbor seals from surveys conducted between 2003 and 2011. This dataset differs from earlier datasets in a few key areas: 1) records generally correspond to a count of the number of harbor seals within a single, geo-referenced digital photo, 2) photographs were not taken when no seals were present so additional analysis of survey effort and flight tracks was required to determine 0 counts.

This dataset contains aerial survey data from the surveys described below. The Bureau of Ocean Energy Management (BOEM), formerly the Minerals Management Service (MMS), and its precursor, the Bureau of Land Management, funded aerial surveys in the Beaufort, Chukchi, and Bering seas from 1979 to 2019. In 2008, through an Interagency Agreement between MMS and the Alaska Fisheries Science Center (AFSC, National Marine Fisheries Service, National Oceanic and Atmospheric Administration [NOAA]), the Marine Mammal Laboratory (MML, a division of AFSC), formerly the National Marine Mammal Laboratory, assumed co-management responsibilities for these surveys. Throughout the history of the surveys, they were referred to as the Bowhead Whale Aerial Survey Project (BWASP) and the Chukchi Offshore Monitoring in Drilling Area (COMIDA) marine mammal aerial surveys, both of which are described in more detail below. The surveys were conducted under the auspices of a single study, Aerial Surveys of Arctic Marine Mammals (ASAMM). In 2020 and 2021, aerial line-transect surveys for bowhead whales and other marine mammals were funded and co-managed by the North Slope Borough (NSB) through contract 2021-069 with the Cooperative Institute for Climate, Ocean, and Ecosystem Studies, a part of the University of Washington, with collaboration from AFSC, NOAA Fisheries. Consistent survey protocol has been in effect on surveys conducted since 1982. WESTERN BEAUFORT SEA Aerial surveys in the western Beaufort Sea (south of 72 degrees N, 140-157 degrees W) have been conducted each year since 1979. MMS personnel and contractors conducted the surveys from 1979 to 2007. From 2008 to 2019, the surveys were conducted by MML. In 2020 and 2021, surveys were conducted by NSB. The primary goal of the project, also known as BWASP through 2010, ASAMM from 2011 to 2019, and NSB Autumn Aerial Surveys in 2020 and 2021, was to document bowhead whales (Balaena mysticetus) during their fall migration through the western Beaufort Sea, although data were also collected for all other marine mammals that were sighted during the surveys. The surveys were typically conducted during the months of September and October, when offshore drilling and geophysical exploration are feasible and when the fall subsistence hunt for bowhead whales takes place near Kaktovik, Cross Island (village of Nuiqsut), and Utqiaġvik (formerly Barrow), Alaska. Additional surveys were conducted in the Beaufort Sea during spring and summer 1979-1986, and during summer 2011 to 2019, and from approximately 15 September to 15 October 2020 to 2021. EASTERN CHUKCHI SEA Aerial surveys in the eastern Chukchi Sea (68-73 degrees N, 157-169 degrees W) were conducted by MMS (now BOEM) contractors from 1982 to 1991. From 2008 to 2019, the surveys were conducted by MML. In 2020 and 2021, the surveys were conducted by NSB in collaboration with CICOES and MML and used a similar methodology to the surveys conducted in previous years. Starting in 2014, surveys were expanded south to 67 degrees N. The goal of the surveys, also known as the Chukchi Offshore Monitoring in Drilling Area (COMIDA) through 2010, ASAMM from 2011 to 2019, and NSB surveys in 2020 and 2021, was to investigate the distribution and relative abundance of marine mammals in the Chukchi Sea Planning Area (CSPA) during the open water (i.e., ice-free) months of June to October, when various species are undertaking seasonal migrations through the area. However, from 1979 to 1984, surveys were also conducted during spring. In 2020 and 2021, NSB Autumn Aerial Surveys in the Chukchi Sea from approximately 15 September to 15 October, were prioritized only when weather conditions were not conducive to surveying the western Beaufort Sea. NORTHERN BERING AND SOUTHERN CHUKCHI SEAS Aerial surveys in the northern Bering and southern Chukchi seas (63-68 degrees N, east of the International Date Line) were conducted by MMS (now BOEM) contractors from 1979 to 1985. The goal

US surveys were conducted of the Bering Sea pack ice for bearded, spotted, ribbon, and ringed seals using digital cameras and thermal imagers mounted in the belly ports of two fixed-wing aircraft from 6 April to 23 May 2012 and 4 April to 9 May 2013. U.S. flights were flown at a target altitude of 1,000 ft (300 m) to maximize the area surveyed while maintaining the required imaging resolution and minimizing the chance of disturbance to seals and other wildlife. A NOAA Twin Otter (N56RF) aircraft housed three FLIR SC645 thermal imagers, which recorded continuous data in the 7.5-13.0 µm wavelength. Each thermal imager was paired with a Canon Mark III 1Ds digital single-lens reflex camera fitted with a 100-mm Zeiss lens. All six instruments were mounted in an open-air belly port. The combined thermal swath width was approximately 1,500 ft (470 m) at an altitude of 1,000 ft. A contracted Aero Commander aircraft carried two sets of paired thermal imagers (SC645) and digital SLR cameras (Nikon D3X) and surveyed a maximum swath width of approximately 900 ft (280 m). Color cameras collected images at a 1-1.2 second interval. In 2013 the two aircraft flew a total of 36 surveys covering more than 17,000 nmi (32,090 km) of trackline and collected about 913,000 images. Combined with the 2012 survey effort, the U.S. BOSS team covered 31,000 nmi of trackline and collected 1.8 million images.

Bearded seals (Erignathus barbatus) are one of the most important subsistence resources for the indigenous people of coastal northern and western Alaska, as well as key components of Arctic marine ecosystems, yet relatively little about their abundance, seasonal distribution, migrations, or foraging behaviors has been documented scientifically. Ice-associated seal populations may be negatively impacted by offshore oil and gas development as well as by climate change. During a cooperative effort between scientists and subsistence hunters in October 2004, 2005, and 2006, 13 female and 13 male juvenile (i.e., age <2) bearded seals (Erignathus barbatus) were tagged with satellite-linked dive recorders (SDRs) in Kotzebue Sound, Alaska. While the focus of this study was on young bearded seals, an additional three female spotted seal (Phoca largha) pups and two adult spotted seal males were captured and deployed with satellite telemetry devices. The data files within this dataset represent the 'raw' data obtained from the Wildlife Computers data portal. Each deployment (unique tag id + animal id combination) is provided as a zipped archive. The root folder also includes additional documentation. The various files and detailed column descriptions are described in the 'Spreadsheet-File-Descriptions.pdf' which was downloaded from Wildlife Computers (https://wildlifecomputers.com/support/downloads/). The '00_kotzeb04_get_data.Rmd' file is an RMarkdown file that provides code and documentation of the data retrieval process. The corresponding '00_kotzeb04_get_data.hml' file is generated from the RMarkdown file.

US surveys were conducted of the Bering Sea pack ice for bearded, spotted, ribbon, and ringed seals using digital cameras and thermal imagers mounted in the belly ports of two fixed-wing aircraft from 6 April to 23 May 2012 and 4 April to 9 May 2013. U.S. flights were flown at a target altitude of 1,000 ft (300 m) to maximize the area surveyed while maintaining the required imaging resolution and minimizing the chance of disturbance to seals and other wildlife. A NOAA Twin Otter (N56RF) aircraft housed three FLIR SC645 thermal imagers, which recorded continuous data in the 7.5-13.0 µm wavelength. Each thermal imager was paired with a Canon Mark III 1Ds digital single-lens reflex camera fitted with a 100-mm Zeiss lens. All six instruments were mounted in an open-air belly port. The combined thermal swath width was approximately 1,500 ft (470 m) at an altitude of 1,000 ft. A contracted Aero Commander aircraft carried two sets of paired thermal imagers (SC645) and digital SLR cameras (Nikon D3X) and surveyed a maximum swath width of approximately 900 ft (280 m). Color cameras collected images at a 1-1.2 second interval. In 2013 the two aircraft flew a total of 36 surveys covering more than 17,000 nmi (32,090 km) of trackline and collected about 913,000 images. Combined with the 2012 survey effort, the U.S. BOSS team covered 31,000 nmi of trackline and collected 1.8 million images.