Antarctica’s southern Weddell Sea is the place to find a mate, if you’re a icefish.
A group of scientists recently discovered about 60 million icefish nests in the seafloor.
As Live Science reports, Autun Purser of the Alfred Wegener Institute and his team of researchers on the RV Polarstern were monitoring the area for marine life when graduate student Lilian Böhringer called up to the bridge. She had been keeping a close eye on the video feed of the seafloor of the Weddell Sea, taken from the Ocean Floor Observation and Bathymetry System (OFOBS), a one-ton camera pulled behind the ship.
Böhringer was seeing fishnests as far as the camera could pick up light.
“The camera was moving [across the seafloor] and it just didn’t stop. They were everywhere,” Böhringer told Live Science.
“We found fish nest after fish nest for four hours,” Purser said. “Nothing but fish nests.”
A majority of the nests were watched over by a single adult fish, and contained about 1,700 eggs, a pattern which repeated in divots across the seafloor for 93 square miles, the largest ever recorded.
According to Axios, researchers have previously only found groups of several dozen icefish nests at a time. So, why have a million times that shown up in the southern Weddell Sea?
One theory is that warmer currents could be easier to navigate, and when flowing together essentially funnel the fish into a single massive breeding colony.
Whatever brought the icefish en masse to the southern Weddell Sea is a boon to local predators and the environment, Purser and team wrote in their study, published in Current Biology.
“Historical and concurrently collected seal movement data indicate that this concentrated fish biomass may be utilized by predators such as Weddell seals,” the study reads. “Numerous degraded fish carcasses within and near the nesting colony suggest that, in death as well as life, these fish provide input for local food webs and influence local biogeochemical processing.”
Since the colony was discovered, efforts are now underway to designate it a Marine Protected Area under the international Commission for the Conservation of Antarctic Marine Living Resources.
Learn more in the video below.