Blue whale behavioral ecology

This collection contains data used in a study of the movement ecology of blue whales in the eastern North Pacific, off central California, USA. The study was published in Ecology Letters in 2022 and is entitled, “Oceanic giants dance to atmospheric rhythms: Ephemeral wind-driven resource tracking by blue whales.” As of this writing, the article does not yet have a DOI. Data include: 1) Acoustic vector sensor (AVS) tracking of blue whale calls Annual periods of blue whale acoustic presence were analyzed across two years to examine the directional distribution of call origin around the MARS cabled observatory. Quality controlled data include the time, bearing, and call index of all manually validated seconds for which the blue whale B-call index exceeded a value of 1.25. These data appear in Figures 4 and 5 of the paper. The files are AVS_2019-2020.RData and AVS_2020-2021.RData. 2) Modeled received levels at the MARS cabled observatory The geographic domain over which received signal is sufficient to reliably estimate the direction of blue whale B-call origin from the MARS cabled observatory was approximated by modeling of acoustic transmission loss. These data appear in Figure 2C of the paper. Model results represent received level (underwater dB) at the MARS cabled observatory, assuming appropriately specified intensity, depth, and frequency of the sound source and oceanographic physical conditions during the time of year when blue whale calling is most active. The file is ModeledReceivedLevel.RData. 3) Animal-borne tag data Data from a biologging tag deployed on a blue whale were used to validate an acoustic vector sensor on the MARS cabled observatory. These data appear in Figure 3 of the paper and include information about whale behaviors (diving, calling, lunge feeding) and surface position from GPS. In addition to identified behavioral events, underlying hydrophone and accelerometer data used to identify behaviors during the period of matchup with AVS data are included. The file is Tag_bw191101-70.RData. 4) Forage species aggregation data The area scattering (sa) within patches in the upper 200 m above the MARS cabled observatory, presented in Figure 5E of the paper, are in the file MARS_sa.RData.