The North Pacific right whale (NPRW) was heavily hunted between the 17th and the 20th centuries. Protection was supposedly afforded by international treaties in the 1930s and 1940s, but the illegal capture of hundreds of individuals by the Soviet Union, primarily in the 1960s drastically impacted the recovery of the species. Currently, only a small remnant of this population (estimated at approximately 30 individuals) inhabits the southeastern Bering Sea (SEBS). There is an increasing body of evidence suggesting that the middle shelf domain constitutes the primary habitat of NPRWs in the SEBS during the summer. Despite substantial observation effort from various sources in some other areas, the only region in the Bering Sea where NPRWs have been consistently seen is the middle shelf. Vessel surveys were conducted in the summers of 2007 - 2011 in the EBS mostly within the NPRW critical habitat boundary (located on the middle shelf of the SEBS). A total of eight NPRW individuals were identified from photographs taken during the survey.

This dataset is a compilation of line-transect data collected on surveys in the Aleutian Islands, Bering Sea, and western and central Gulf of Alaska, 2001 - 2010. All the surveys were conducted with similar methods using line-transect protocols, allowing effort to be quantified, but there were differences in transect design in some years (some surveys were systematic, some were not). Sighting information for all cetacean and at-sea pinniped species was collected. The database was compiled with the intent of including all surveys with sighting data on killer whales, in order to assess killer whale population biology in this region. Surveys included in this database are 2001 - 2007, 2009 and 2010 NMML killer whale surveys.

The Minerals Management Service (MMS), previously Bureau of Land Management, has funded fall bowhead whale aerial surveys in this area each year since 1978, using a repeatable protocol from 1982 to the present. Bowhead monitoring by MMS Environmental Studies Section, Alaska Outer Continental Shelf (OCS) Region, normally overlaps the September-October "open-water" season when offshore drilling and geophysical exploration are feasible and when the fall subsistence hunt for bowhead whales takes place near Kaktovik, Nuiqsut, and Barrow, Alaska. The primary survey aircraft was a de Havilland Twin Otter Series 300. The aircraft was equipped with three medium-size bubble windows that afforded complete viewing of the track-line. Geographic positions of the aircraft were logged onto a laptop computer from a Global Navigation System (1982-1991) or a Global Positioning System (1992-2000). Prior to 1992, many surveys in Block 12 (See Browse Graphic) were conducted from a Grumman Turbo Goose Model G21G. All bowhead (and beluga) whales observed were recorded, along with incidental sightings of other marine mammals. Particular emphasis was placed on regional surveys to assess large-area shifts in the migration pathway of bowhead whales and on the coordination of effort and management of 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. Otherwise, the project attempted to distribute effort fairly evenly east-to-west across the entire study area. Aerial coverage favored inshore survey blocks (See Browse Graphic), since bowheads were rarely sighted north of these blocks in previous surveys (1979-1986). Surveys were flown at a target altitude of 458 m in order to maximize visibility and to minimize potential disturbance to marine mammals. Flights were normally aborted when cloud ceilings were consistently less than 305 m or the wind force was consistently above Beaufort 4. Daily flight patterns were based on sets of non-repeating transect grids computer-generated for each survey block. Transect grids were derived by dividing each survey block into sections 30 minutes of longitude across. One of the minute marks along the northern edge of each section was selected at random then connected by a straight line to a similarly selected endpoint along the southern edge of that same section. This procedure was followed for all sections of that survey block. These transect legs were then connected alternately at their northernmost or southernmost ends to produce one continuous flight grid within each survey block. Gridlines were occasionally lengthened to cover both an inshore block and the block north of it. Lines were occasionally truncated due to extended poor visibility or to avoid potential interference with subsistence whaling activities. For bowheads encountered "on transect", the aircraft sometimes circled for a brief (< 10 min) period to observe behavior, obtain better estimates of their numbers, and/or determine whether calves were present. Any new groups sighted when circling were recorded as "on search".

This dataset describes marine bird and mammal surveys conducted in August 2012-2014 in the North Pacific Ocean and Bering Sea. Data were collected to document the at-sea distribution and abundance of marine birds and mammals, and were conducted using standard strip width transect protocols (Gould and Forsell 1989). One observer and one recorder identified and counted birds on transect at all times. Surveys were recorded using a DLOG system and exported into a .csv file. This dataset contains survey data consisting of: date, time, latitude, longitude, record number, data type, species, count, behavior, distance, observers, observer conditions, trip ID, beaufort, transect type, transect width (m), and comments.