This data set contains vessel- and aircraft-based marine mammal surveys in the Chukchi Sea collected from 1989 to 1991. The aerial marine mammal surveys were conducted by EBASCO to determine the response of walrus to drilling operations in the northern Chukchi Sea at the Crackerjack, Burger and Popcorn prospects between June 29 and October 11, 1990 and at the Crackerjack and Diamond prospects between July 29 and October 8, 1991. The vessel-based marine mammal observations data were collected in the Chukchi Sea in 1989 - 1990. Monitoring efforts were implemented in 1989 by Shell to determine effects of exploratory drilling operations on walrus and polar bears. Results were submitted to regulatory agencies in 1990.

This dataset contains vessel- and aircraft-based mammal sightings data and associated environmental data collected in the Chukchi and Beaufort seas during the open water season 2006-2010. The aerial data are derived from marine mammal observers aboard aircrafts flown at 1000 ft to 1500 ft. The data contains marine mammal sightings data and associated environmental data collected during the open water season 2006-2010 (excluding 2009) in Chukchi Sea and Beaufort Sea. In addition, this metadata describes aerial navigational GPS data recorded during observations. Data collection methods changed slightly between years. The metadata for each attribute should be studied carefully before these data are used for analyses.

Whale monitoring biological data was collected from Chukchi Sea by Sea World Research Institute, San Diego, CA. The data was collected over three month period spanning from September 20 to November 3, 1989. The data submitted by Ms. Karen M. McClune has been processed by NODC and is available in F127-Marine Animal Sightings file format.

The aerial surveys of Whales data in this accession were collected from aircraft by Don Llungblad over the Chukchi Sea between September 1987 and October 1988 by Sea World Research Institute, San Diego, CA. The data were submitted by Ms. Karen M. McClune in a tape. The data have been processed and are available in F127-Marine-Animal-Sightings file format of NODC.

Individual Animal and other data were collected using visual observation and other instruments from AIRCRAFT in the Bering Sea, Chukchi Sea, and Arctic Ocean. Data were collected from 02 September 1990 to 07 November 1991 by US DOI; Minerals Management Service in Anchorage (MMS). Data has been processed by NODC to the NODC standard Marine Mammal Sighting and Census (F127) format. The F127 format is used for data from field observations of marine animals. Data may be reported either for individual, random sightings or for sightings made as part of systematic ship or aircraft surveys along specified tracks. These data provide information on animal population densities and distributions, activities, migratory routes and breeding locales. Cruise or survey information, start and end positions, start and end times, and platform speed, direction, and altitude are reported for each observation or series of observations. Position, date and time are reported for each sighting location, along with a code indicating presence or absence of animals and, if present, their distance to the observer, shoreline, and ice edge and heading direction. For each sighting location, animal sighting data are reported by species for all observed species. Species identification, total number of individuals, and counts by age group (adults, subadults, juveniles, unknown) may be reported in summary for all animals sighted or by subgroups distinguished by sex, behavior, markings, or other characteristics. A text record is available for comments.

These data are part of a multi-year baseline environmental studies data set collected as part of the permitting process prior to drilling exploration wells. The objectives of the Chukchi Sea Environmental Baseline Studies Program are: 1. To provide data for pre-exploration and development-related activities 2. To provide data for permit applications 3. To provide input to planning of future operations and associated mitigation 4. To provide additional baseline data that can be used to assess and measure the potential environmental effects of offshore oil and gas exploration and development in the northeastern Chukchi Sea. These data were submitted under Annex 1 of the Memorandum of Understanding between NOAA and the oil companies (NOAA Agreement NOS-MOA-2011-080).

All marine mammals and sea turtles that were visually observed during a marine geophysical survey were recorded to: 1) determine whether a mitigation measure needed to be implemented during the survey; 2) determine the potential number of animals exposed to seismic sounds. During periods when no marine mammals were observed, the vessel location and the environmental conditions were also recorded approximately every 30 minutes whenever a Protected Species Observer was on watch (during daylight hours).