Unlocking the Secrets of Antarctic Krill from the Ocean Floor

Antarctic krill may be small, but they play an outsized role in one of the planet’s most important ecosystems. To better understand their behaviour throughout the year, the Australian Antarctic Division (AAD), together with CLS Oceania and technology partner Develogics, has deployed KOMBI landers on the seafloor beneath Antarctic waters, collecting valuable data in conditions that are otherwise inaccessible to researchers.

We spoke with Bryan Murphy, Oceanographic Technician & Sales at CLS Oceania, about why krill matter, the scientific objectives behind the project, and the challenges of conducting research in one of the most extreme environments on Earth.

A cornerstone of the Antarctic ecosystem

“Krill is a fundamental part of the Antarctic ecosystem and is considered to have the greatest biomass of any non-domestic animal on Earth,” explains Bryan.

These small crustaceans form the foundation of the Antarctic food web. Feeding on diatom phytoplankton, krill provide a vital link between microscopic marine life and many of Antarctica’s most iconic species, including fish, whales, seals, penguins and seabirds.

Their importance extends beyond the Southern Ocean ecosystem. Krill also play a significant role in the global carbon cycle. Diatoms absorb carbon dioxide through photosynthesis and are then consumed by krill. As krill feed and produce waste, carbon is transported to the deep ocean, where it can remain locked away for thousands of years.

“Although each individual krill only processes a tiny amount of carbon, their immense populations collectively perform an incredible service for our planet,” says Bryan.

Studying krill year-round beneath the ice

Much of what scientists know about Antarctic krill comes from research conducted during the austral summer, when vessels can access ice-free waters using acoustic surveys and trawling methods. However, the harsh Antarctic winter remains largely unexplored.

“The challenge is that research ships can only operate in the region during summer,” explains Bryan. “Once winter sea ice forms, access becomes extremely limited.”

To overcome this limitation, the Australian Antarctic Division deploys KOMBI landers on the seafloor during the summer season. The autonomous systems then remain in place throughout the Antarctic winter, continuously collecting data before being recovered the following year.

The landers are equipped with a suite of scientific instruments, including an acoustic Doppler current profiler (ADCP) with echosounder capabilities for estimating krill biomass, stereo high-definition cameras to observe krill and other marine species, oceanographic sensors measuring temperature and salinity, and underwater acoustic recorders that capture the calls of whales and seals that depend on krill as a food source.

Perhaps most importantly, the KOMBI landers provide a completely new perspective on Antarctic ecosystems.
“Traditional krill biomass estimates typically focus on waters shallower than 250 metres,” says Bryan “The KOMBI systems collect observations from depths down to 1,500 metres, allowing us to understand what’s happening much deeper in the water column.”

Operating in one of the world’s harshest environments

Deploying scientific equipment thousands of metres below the ocean surface in Antarctica requires careful planning and patience.
Because access to the region is restricted to a short summer window, each deployment is effectively a year-long commitment. A lander deployed one season is not recovered until the next.

“If a deployment or recovery opportunity is missed because of weather or logistical constraints, we may have to wait another full year,” explains Bryan. “Ship time in Antarctica is extremely limited and therefore very valuable.”

The success of every mission depends on ensuring that the landers can withstand months of isolation in deep, freezing waters while continuing to collect data reliably until recovery.

Collaboration driving Antarctic science

The project highlights the importance of collaboration between scientific institutions and technology specialists.

The Australian Antarctic Division brings world-leading expertise in Antarctic research, supported by its state-of-the-art icebreaking research vessel, RSV Nuyina. CLS Oceania contributes extensive experience in metocean services and oceanographic instrumentation, while Develogics provides the KOMBI lander platform itself.

“Together, we adapted the system specifically for Antarctic conditions and equipped it with the instruments needed to support krill research,” says Bryan.

The partnership continues to evolve. Building on lessons learned from the first generation of landers and their deployments, CLS Oceania has recently delivered the KOMBI Mk2 system to the AAD. The upgraded version incorporates improvements to the camera and lighting systems, a new acoustic recorder, and enhanced recovery features designed to maximize the chances of successful retrieval after a year on the seafloor.

“Recovering a lander and the valuable data it contains after a year in the deep ocean is a challenge in itself,” notes Bryan. “Every improvement helps ensure that these unique observations make it back to the scientists who depend on them.”

By combining scientific expertise, innovative technology and long-term commitment, the Australian Antarctic Division and its partners are helping unlock new insights into Antarctic krill and the ecosystems that depend on them, advancing our understanding of one of Earth’s most critical and least accessible environments.