This dataset contains the utilization distributions for all tagged Guadalupe fur seals in 2018-2019, and 2020. In these maps, the red shading represents more intensely used areas, while the yellow shading represents less intensely used areas. This research was funded by the U.S., Commander Pacific Fleet.

As the population of Guadalupe fur seals (Arctocephalus townsendi or A. philippii townsendi) continues to recover, this species, which is listed as threatened in the U.S. and endangered in México, is increasingly common in their historical range extending from central México to Washington State. Relatively little is known about this species compared with other pinnipeds that occur in the California Current System. Accurate and current population estimates are lacking because censuses at the only rookery have been sparse and sporadic, and there is a paucity of data on at-sea movements because few individuals have been tracked using telemetry instruments. Therefore, the goal of this multiyear study was to better understand Guadalupe fur seal abundance, behavior, distribution, and habitat use, and to determine the degree to which this recovering population uses U.S. Navy training and testing ranges in the Northeast Pacific.

As part of this study, censuses were performed at Guadalupe Island, México and San Benito Archipelago, México in summer 2018 and 2019. Satellite-linked time depth recorders were deployed on adult females (n = 30, 15 per year), juvenile females (n = 20, 10 per year) and juvenile males (n = 20, 10 per year) at Guadalupe Island in November 2018 and March 2020, and satellite location-only transmitters were deployed on pups (n = 30) at Guadalupe Island in March 2020.