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Tracking Data for Pacific Walrus (Odobenus rosmarus divergens)

July 8, 2022

This metadata document describes the data contained in the "processedData" folder of this data package. This data package contains all data collected by the Argos System from 921 satellite transmitters attached to adult Pacific walruses in the Bering and Chukchi Seas, in U.S. and Russian waters, 1988-2019. The raw data were processed to accomplish two goals: flag implausible location estimates and decode raw sensor data. Very few transmitters (n=5) also carried GPS receivers. Because the GPS locations were communicated through the Argos System, a time series of Argos (Doppler) tracking data for those 5 transmitters also exists and is included. Four Comma Separate Value (CSV) tables are included in the "processedData" folder of this data package: 1) the "GPS_filteredLocations" table contains one record for every GPS location obtained, accompanied by a binary flag that denotes an algorithm's plausibility check (based on a speed threshold of 35 m/s); 2) the "diag_filteredLocations" table contains one record for every Argos location estimate collected, accompanied by a binary flag that denotes an algorithm's plausibility check (based on distance, turning angle, and rate thresholds). Each record in both the GPS and Argos filtered-location tables also includes a 'Tracking_Status' variable that denotes whether the location was collected from a live animal, a dead animal, or shed transmitter, 3) the "decodedSensor" table contains decoded sensor data such as the transmitter's temperature, battery voltage, and motion (activity), and 4) the "deploymentAttributes" table contains one record for each transmitter deployment in a CSV formatted table. The deployment attributes file contains information such as when the transmitter was attached to the animal, when tracking of a live animal ended, and a variety of variables describing the animal and transmitter. This table is identical to the "deploymentAttributes" table in the "rawData" folder of this data package. This metadata document describes the data contained in the "rawData" folder of this data package. This data package contains all data collected by the Argos System from 921 satellite transmitters attached to adult Pacific walruses in the Bering and Chukchi Seas, in U.S. and Russian waters, 1988-2019. Five data files are included in the "rawData" folder of this data package. Two data files (with identical content) contain the raw Argos DIAG (Diagnostic) data, one in the legacy verbose ASCII format and one in a tabular Comma Separated Value (CSV) format. Two other data files (with identical content) contain the raw Argos DS (Dispose) data, one in the legacy verbose ASCII format and one in a tabular CSV format. The fifth file, "deploymentAttributes", contains one record for each transmitter deployment in a CSV formatted table. The deployment attributes file contains information such as when the transmitter was attached to the animal, when tracking of a live animal ended, and a variety of variables describing the animal and transmitter. This table is identical to the "deploymentAttributes" table in the "processedData" folder of this data package.

Publication Year 2022
Title Tracking Data for Pacific Walrus (Odobenus rosmarus divergens)
DOI 10.5066/F7FQ9TP6
Authors Chadwick V Jay, Anthony S Fischbach, Anatoly A. Kochnev, Susan Hills, David C Douglas
Product Type Data Release
Record Source USGS Digital Object Identifier Catalog
USGS Organization Alaska Science Center