In this episode of the "How to Protect the Ocean" podcast, host Andrew Luen discusses a remarkable predation event that occurred in 2014 in the Barents Sea off the coast of Norway. During this event, approximately 2 million Atlantic cod consumed around 10 million capelin, which is nearly 50% of the capelin population present at the time.

The episode highlights how this massive predation event was observed using advanced technology, specifically the Ocean Acoustic Waveguide Remote Sensing System (O-A-W-R-S). This system allowed scientists from MIT and Norway to detect and analyze the behavior of the fish during the capelin's spawning season. As the capelin swam deeper to avoid sunlight, they formed a large bait ball, which measured about 10 kilometers long and contained around 23 million fish.

The podcast emphasizes the significance of this event as it represents one of the largest predation interactions ever recorded. The coordinated attack by the cod and the formation of the bait ball illustrate the complex dynamics of predator-prey relationships in marine ecosystems.

Additionally, Andrew discusses concerns regarding the impact of climate change on these fish populations and their spawning behaviors. He raises questions about the sustainability of such large predation events in the future, considering the potential effects of environmental changes on both capelin and cod populations. The episode concludes with a call for listeners to engage in discussions about ocean conservation and share their thoughts on this fascinating topic.

Link to article: https://www.theinertia.com/environment/oceans-largest-predation-event-ever-seen-recorded-by-oceanographers/