• Description

Intermediate-duration archival tags were attached to eight blue whales (Balaenoptera musculus; four females, three males, one of unknown sex), and five fin whales (B. physalus; two females, one male, two of unknown sex) off southern California, USA, in summer 2014 and 2015. Tags logged 1-Hz data from tri-axial accelerometers, magnetometers, and a depth sensor, while acquiring Fastloc GPS locations. Tag attachment duration ranged from 18.3 to 28.9 d for blue whales and 4.9–16.0 d for fin whales, recording 1,030–4,603 dives and 95–3,338 GPS locations per whale across both species. Feeding lunges (identified from accelerometer data) were used to characterize "feeding bouts" (i.e., sequences of feeding dives with

Scales of Blue and Fin Whale Feeding Behavior off California, USA, With Implications for Prey Patchiness