Krill are small crustaceans—shrimp-like animals—found in all the world’s oceans, including Antarctica. Krill mostly feed on marine algae, and sometimes on zooplankton, which are microscopic ocean animals.
The Krill and Oceanography Research Program focuses on the link between prey production, prey availability, and climate variability in relation to predator and fishery demands. Penguins, seals, whales, and other seabirds prey on krill, which is a significant food source for these predators.
Human demand for krill is increasing, driving the krill fishery to catch more and more krill. Penguins, seals, and fishermen may compete for krill in the same areas. Our studies help decide how much krill fishermen are allowed to catch in areas where penguins and seals feed while raising their young.
Historically we studied krill using ship-based net and acoustic technology that estimated krill abundance. Beginning in austral summer 2018 to 2019, this research program began to use autonomous long-duration acoustically equipped gliders and moorings to conduct surveys that allow for a more focused look at predator-prey relationships and has allowed us to continue to monitor trends in krill abundance over time. This shift towards autonomous instrumentation also serves as a unique pilot for moving NOAA Fisheries towards the integration of this instrumentation into other fisheries programs.
Our gliders are deployed in the waters of Antarctica for three months every year, and are piloted by staff located in La Jolla, California.The gliders not only collect data on krill location and abundance but also collect oceanographic data such as temperature and salinity, which help us understand how changes in the ocean may affect krill populations.
We also deploy stationary moorings that sit far underwater in areas where penguins and seals feed. Moorings use sound to “see” krill drifting over them. Moorings tell us how and in what directions krill move through areas where penguin and seals feed, which helps us understand the “supply” of krill to meet the demands of hungry predators.