A team of researchers has captured some epic footage of a sailfish hunt—from the perspective of the sailfish. The researchers from Nova Southeastern University Guy Harvey Research Institute designed a tag with high-tech sensors and a Go Pro-like video camera. After catching sailfish while fishing from Tropic Star Lodge in Panama, they tagged and released their catches. The research was initially meant to show how sailfish recovered from being caught by fishermen but instead, the researchers shifted their focus to sailfish predation.
According to the study’s authors, relatively little is known about the hunting patterns of sailfish, which are considered the fastest fish on the planet. The most commonly-known type of sailfish hunting occurs when the apex predators group up and attack baitfish, using their sharp bills to slash and stun their prey. These predation events are easily seen by people because they occur entirely at the surface level of the ocean. But the recent research looked at what happens when sailfish hunt alone.
“Most of the day they dive back and forth between the surface and the thermocline layer, where the water gets cold. The thermocline can concentrate prey that don’t want to enter the cold water, so it looks like the sailfish might be using this to its advantage,” lead author Ryan Logan told Phys.org. “Most of what you see in the videos is just a lot of blue water, but when I saw the sailfish start to swim really fast toward the surface, I knew something was up.”
The researchers captured footage of a 100-pound sailfish blitzing the surface of the ocean from a depth of 200 feet in pursuit of a small tuna. The sailfish charges the tuna several times, each time splashing at the surface of the water, before successfully killing the tuna. Researchers say that the footage, along with measurements of metabolic rates of sailfish, is a step towards understanding previously unknown aspects of sailfish biology such as how often they need to eat.
“While the energetic gains from this predation event were substantial compared to what was expended during the pursuit, the amount of energy burned in search of prey over the course of the day and night was considerable,” wrote the researchers. “The approach we have taken could be used as a starting point to inform future energetic and trophic models and improve our understanding of the role of these pelagic predators in our oceans.”