The Intriguing Mating Dance of Krill in the Southern Ocean
Chase, probe, embrace, flex, push. It’s probably too much information, but that is how krill mate. This fascinating behavior was recorded on a deep-sea camera 500 meters below the surface of the Southern Ocean back in 2011 by Australian Antarctic Division researchers – who then made an animated illustration of this special “dance.”
Krill, tiny shrimp-like creatures, play a crucial role in the marine ecosystem. They can change from adults to juveniles and survive over 200 days of starvation by reducing their size using body proteins rather than molting their exoskeleton. Krill are a vital food source for whales, seals, and penguins and help sequester carbon deep in oceanic waters as their exoskeletons and feces sink to the seafloor.
However, krill populations are at risk due to overfishing, climate change, and ocean acidification. A new project to monitor their population from space was recently announced by researchers from the University of Strathclyde, WWF, and the British Antarctic Survey. This monitoring effort was made possible by the identification of the signal associated with the pigment that turns krill red.
It is estimated that there could be up to 500 million tons of krill swimming (and mating) in the Southern Ocean, equivalent to the biomass of all the cattle or humans on Earth. Despite their significant role in carbon sequestration, a recent study suggested that a greater percentage of their feces might degrade before reaching the seabed, impacting their carbon export efficiency.
Researchers from the Australian Antarctic Division used a seafloor lander to monitor the daily migration patterns of krill using video cameras and echo sounders. They found that krill’s vertical migration is more pronounced in winter when there is less carbon to export, with only a portion of the population migrating over the year.
To aid in long-term subsea scientific research, SubC Imaging announced an enhanced autonomous timelapse camera system with a hibernation mode that conserves battery power, allowing for months or even years of continuous operation. This system can be integrated with various setups, making it suitable for exploring more of nature’s subsea ecology and potentially capturing more of these intriguing krill mating dances.
As researchers continue to study krill populations and their ecological impact, it is evident that there is still much to learn about these tiny yet critical creatures in the vast Southern Ocean.