Krill swarms detected with active acoustic EK80 onboard small boat surveys in Palmer Deep Canyon, Antarctica during January-March 2020

These data include identified krill swarms observed by a hull-mounted SIMRAD EK80 single-beam, single frequency (120 kHz) echo sounder (Kongsberg Maritime) hereby referred to as “EK80”. Data were collected in Palmer Deep Canyon, Antarctica during January-March 2020. Small boat surveys were conducted twice weekly over known penguin foraging areas. EK80 data were processed using Echoview software and backscattering zooplankton were identified as krill when within a target strength of -70 dB to -30 dB.

The EK80 survey was designed in concert with the ACROBAT, HFR and mooring observations to provide a wholistic view of the food web. Observing the distribution of krill swarms and their correlation with other ecosystem variables is important for understanding how the Palmer Deep ecosystem, and other coastal ecosystems globally, respond to complex coastal ocean currents and ways this system may be resilient to rapid warming. The collection and processing of these data was headed by Ashley Hann and Dr. Kim Bernard.