This dataset provides counts of harbor seals from aerial surveys over Iliamna Lake, Alaska, USA. The data have been collated from three previously published sources (Mathisen and Kline 1992; Small 2001; ABR Inc. Environmental Research and Services 2011) and newly available data from the NOAA Alaska Fisheries Science Center and the Newhalen Tribal Council. The survey years range between 1984 and 2013. Counts are reported as summed totals across all identified waypoints in the lake for each survey date. The NOAA National Marine Mammal Laboratory (NMML) (Alaska Fisheries Science Center, Seattle, Washington, USA) conducted aerial surveys of Iliamna Lake between 2008 and 2013. Surveys were conducted as part of annual harbor seal survey effort and in collaboration with local community participants and researchers at the University of Alaska. Surveys were flown using high wing, twin engine aircraft (Aero Commander 680, 690 or a de Havilland Twin Otter). Survey altitude was generally 330 m and at an aircraft speed of 120 kts. Surveys were performed seasonally for most years between 2008 and 2013. Surveys were timed so that one survey was conducted while the lake was mostly frozen (Late March/early April), one during pupping (mid July), and often several during the August molt, when the greatest number of seals typically haul out on shore. Surveys were flown, weather allowing, in the mid- to late-afternoon, when the number of seals hauled out was expected to be highest. Aircraft flight track was recorded by GPS and all seals sighted were digitally photographed using a high resolution digital SLR camera with a telephoto zoom lens (up to 400mm). Time, date, latitude, longitude, and altitude were automatically saved into the image metadata or georeferenced post survey using the GPS track and software. The total number of seals hauled out were counted from the digital photographs and recorded for each identified site. Pups were determined by their smaller size, and close proximity (less than 1 body length; either nursing or laying right next) to a larger seal. Pups were no longer recorded beyond about mid-August when many have been weaned and cannot reliably be distinguished from other non-adult seals. In 2009, a collaborative effort between NMML and researchers from the Newhalen Tribal Council (Newhalen Tribal Council 2009) provided 10 additional surveys and similar techniques were used. The raw survey count data from these surveys was provided to NMML. Aerial surveys were authorized under a Marine Mammal Protection Act General Authorization (LOC No. 14590) issued to the NMML. Between 2005 and 2007, ABR, Inc. Environmental Research and Services conducted a series of aerial surveys for harbor seals in Iliamna Lake (ABR Inc. Environmental Research and Services 2011). In addition, earlier counts from surveys conducted by ADFG (Small 2001) and a 1991 census by Mathisen and Kline (Mathisen and Kline 1992) were incorporated into the dataset to expand the historical reach. Geographic coordinates were provided (or, when not provided, determined based on descriptions or phyiscal maps) for each survey site and these sites were compared and merged with locations identified by NMML. In some cases, sites in very close geographic proximity were combined into a single site.

Aerial surveys of coastal Alaska are the primary method for estimating abundance of harbor seals. A particular challenge associated with aerial surveys of harbor seals is maintaining consistent spatial representation of haul-out locations (waypoints). In some cases, seals aggregate into a single large grouping at a particular area. In other cases, seals aggregate into several smaller groups spread over a particular area. To establish geo-spatial consistency, the Alaska Fisheries Science Center (AFSC) maintains a list of haul-out locations that represent known harbor seal aggregations in Alaska. Haul-out locations were identified through aerial survey efforts and historical knowledge. Locations are assigned a unique alphanumeric identifier, based on the survey unit they fall within, and the spatial data are provided in the geographic (epsg:4326) coordinate reference system. These haul-out locations are used to inform management decisions pertaining to coastal activities (presence/absence of seals in a particular area) and to facilitate AFSC field work that includes both aerial and vessel surveys. Haul-out locations are updated annually based on information obtained from aerial survey observations. This dataset contains Alaska harbor seal haul-out locations that are recorded primarily to support aerial survey efforts in August and (in some areas, June). Harbor seals are known to use various haul-out locations seasonally and, thus, this is likely not a complete collection of harbor seal haul-out locations. Some haul-outs that are close together may be combined and represented as one site or waypoint. Important haul-out locations have been identified in the "status" field of the attribute table and are labeled as "key haulout" if a particular location contains 50 or more harbors seals. A haul-out location containing less than 50 harbor seals is labeled "not key haulout". This number may change as more in depth analysis continues.

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 data layer represents the 12 uniquely identified stocks of harbor seals found in Alaskan waters. Stocks were identified by NMFS and their co-management partners, the Alaska Native Harbor Seal Commission, in 2010 based largely on genetic structure. Given the genetic samples were not obtained continuously throughout the range, a total evidence approach was used to consider additional factors such as population trends, observed harbor seal movements, and traditional Alaska Native use areas in the final designation of stock boundaries. The 12 stocks of harbor seals currently identified in Alaska are 1) the Aleutian Islands, 2) the Pribilof Islands, 3) Bristol Bay, 4) North Kodiak Island, 5) South Kodiak Island, 6) Prince William Sound, 7) Cook Inlet/Shelikof Strait, 8) Glacier Bay/Icy Strait, 9) Lynn Canal/Stephens Passage, 10) Sitka/Chatham Strait, 11) Dixon/Cape Decision and 12) Clarence Strait.

These data sets were used by Zeppelin et al. (2015) to model northern fur seal foraging habitats based on stable isotope values measured in plasma and red blood cells, and satellite-linked tag measures of locations and diving behavior. Foraging habitat models were developed using blood isotope samples collected from 35 adult female fur seals on three breeding colonies in Alaska during July-October 2006. Satellite location and dive data were used to define habitat use in terms of the proportion of time spent or dives made in different oceanographic/bathymetric domains. Stable isotope samples, dive data, and GPS location data collected from 15 females during August-October 2008 validated model use across years.

Aerial surveys were conducted to produce abundance estimates for the three Alaska stocks of harbor porpoise. Surveys occurred from May to July 1997 for the Southeast Alaska stock, May to July 1998 for the Gulf of Alaska stock, and June to July 1999 for the Bering Sea stock. Two primary observers observed from bubble windows on the left and right side of the plane. A belly window observer with a view directly down along the trackline collected sightings that were matched to the side observers and used to estimate a correction factor for perception bias that was specific to harbor porpoise in Alaskan waters.

This dataset contains GIS layers that depict the known spatial distributions (i.e., ranges) and reported breeding areas of spotted seals (Phoca largha). It was produced as part of a U.S. Endangered Species Act status review, which included delineating the species in question and assessing its risk of extinction within the foreseeable future throughout all or a significant portion of its range. Its boundaries are based on previously published range maps and/or descriptions of the species' distribution in published or unpublished accounts. All boundaries should be considered approximate.

The National Marine Fisheries Service (NMFS) has conducted aerial counts of Cook Inlet beluga whales (Delphinapterus leucas) from 1993 to 2012, 2014, 2016, 2018, 2021, and 2022. Nearly all counts were conducted during the month of June. The routine nature of these counts and the consistency in research protocol lend themselves to inter-annual trend analyses. Beginning in 2005, an aerial survey was added during the month of August to document calving groups within the upper Inlet (north of East and West Foreland). Research protocol has been based on paired observers on the shoreward side of the aircraft and a single observer and computer operator on the offshore side independently searching for marine mammals. Data on environmental conditions, time, location, species, and inclinometer angle were collected for each sighting. The counting protocol included multiple passes near each beluga group while simultaneously collecting video footage. The counting system and observer performance has been tested through paired, independent observational effort. Information about the Cook Inlet beluga whale projects conducted at NOAA can be found here: https://www.fisheries.noaa.gov/species/beluga-whale#science.

This dataset contains GIS layers that depict the known spatial distributions (i.e., ranges) of the two subspecies of bearded seals (Erignathus barbatus). It was produced as part of a U.S. Endangered Species Act status review, which included delineating the species in question and assessing its risk of extinction within the foreseeable future throughout all or a significant portion of its range. Its boundaries are based on previously published range maps and/or descriptions of the species' distribution in published or unpublished accounts. All boundaries should be considered approximate. The approximate North American boundary between the two sub-species was changed to 130W (from 112W), based a re-analysis of the genetic data.

NOAA Fisheries Alaska Regional Office and Alaska Fisheries Science Center’s Auke Bay Laboratories designed the Nearshore Fish Atlas of Alaska (NFA) to provide access to available data on the distribution, relative abundance, and habitat use of nearshore fishes in Alaska. The NFA is a spatially explicit, unified database of numerous nearshore catch datasets collected by various agencies and organizations in Alaska over the past several decades. The compiled datasets are from dozens of studies with different objectives and gear types (e.g., beach seines, purse seines, and trawls). The online NFA application has spatial and tabular tools for extensive searching, filtering, and downloading fully attributed data.