2017-2018 USAP Field Season
Foraging behavior and ecological role of the least-studied Antarctic krill predator, the Antarctic minke whale (Balaenoptera bonaerensis)
Dr. Ari Seth Friedlaender
University of California Santa Cruz
Supporting Stations: ARSV Laurence M. Gould
Researchers will measure the underwater behavior of minke whales to better understand how they exploit the sea-ice habitat. They will use video-recording motion-sensing tags to determine where and when the whales feed and unmanned aerial systems (UAS) to determine how much time whales spend in sea ice versus open water, and how their behavior changes between those two habitats. They will also use scientific echosounders to characterize the prey field that the whales are exploiting and will investigate the differences in krill availability in and out of the ice. The acquired information will help better understand the ecological role of Antarctic minke whales so that better predictions can be made regarding impacts of climate change, not only on these animals, but on the structure and function of the Antarctic marine ecosystem.
Field Season Overview
In the 2017-18 season the researchers will locate aggregations of minke whales in the Joinville Island vicinity. As a contingency plan, if weather conditions do not allow access to Joinville Island in the 2017-18 season, the science team will travel instead to the Gerlache Strait, Wilhelmina Bay, Andvord Island Bay, and Crystal Sound area. Team members will place multi-sensor suction cup tags on whales and will conduct focal animal follows while the tags are attached. Tags are designed to remain on the whale for up to 24 hours, after which time they release passively and float to the surface where they are retrieved using a hand-held radio receiver. The team aims to deploy 10 tags per season. Concurrent to this, a second small boat will launch with a transom-mounted Simrad echo sounder system to map prey in close proximity to the tagged whale. During this time, the LMG will conduct bay-scale prey mapping surveys with a second set of echo sounders that will be brought on board. The science team will conduct net tows in each bay or location to generate a stratified length-frequency distribution estimate of the krill prey field. The science team will require the use of two small boats as well as a 1-meter net tow, standard CTD (no water samples), and underway systems to collect environmental data. It is also planned to collect data via Unmanned Aerial Systems (UAS) while whales are present.
Deploying Team Members