The acoustic data collected in Glacier bay from 2005 2007 was used to study the link between marine predator (harbor seals) diving behavior to local prey fields in contrasting habitats in a glacial fjord. Standardized acoustic surveys were setup and run monthly throughout the summer and throughout Glacier Bay. Fish species were identified from previous trawl surveys while acoustic data was used to locate prey within the bay and water column in association with Harbor seals. Acoustic equipment were calibrated each month and the data were analyzed by the same qualified acoustician throughout the surveys duration. Seals were identified, enumerated and GIS positioned in association with prey fields found with the acoustics.

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 haulout locations. 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 developed coastal survey units (spatial polygons) throughout the distriubtion of harbor seals in Alaska. Each survey unit was designed to be approximately 10-15 kilometers in coastal length, to faciliate efficient aerial surveys, and to aggregate known harbor seal haulout locations. Each survey unit was assigned a unique alphanumeric identifier and the spatial data are provided in the geographic (epsg:4326) coordinate reference system. The survey units form the spatial foundation for estimation of harbor seal abundance and trend.

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.

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.

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.

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.

This dataset contains information regarding the capture and tagging of northern fur seals on the Pribilof Islands and Bogoslof Island, Alaska, from 1992 to 2017.

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).

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.

In the spring of 2007 and 2008, researchers from the Alaska Fisheries Science Center conducted aerial surveys for ribbon, bearded, and spotted seals in the US sector of the Bering Sea. The surveys were conducted from helicopters based aboard the US Coast Guard icebreakers Healy and Polar Sea. Line transect surveys were conducted between approximately 09:00 and 16:00 (local solar time), which corresponds to the timing of peak seal haul-out probability. By local solar time, we mean that for each 15° of latitude west of 0 degrees longitude, one hour was subtracted; thus, we used UTC minus 11 h for Bering Sea observations which puts the sun overhead at approximately noon at these coordinates. Each flight had two to three observers and was flown at a target altitude of 118m (400 ft) at speeds of 80–95 knots. Only seals hauled out on ice were observed and recorded. The distance from each seal to the helicopter’s track line was calculated using a sighting bar mounted on each observer’s window. In all, 2214 seals were observed during approximately 73 h of survey effort covering 11819 km of survey line on 63 flights. Because ice conditions decayed markedly toward the end of the 2007 surveys, our analysis used only the first 27 flights. The number of ringed seal sightings was low, possibly due to a combination of a preponderance of survey effort away from near-shore areas favored by ringed seals and a greater tendency for ringed seals to be disturbed into the water by the helicopter, and therefore to be missed by observers.