If you’ve ever been out on a boat and watched fish gliding or jumping along in the wake, you know they’re pretty darn fast.

But which one is the fastest?

The answer is the billfish, which are saltwater predators with large, pointy bills.

The fastest of the swifty billfish is the sailfish, but there is some debate over whether or not the bluefin tuna could knock them off their throne.

Sailfish have to be able to swim fast in order to hunt. A member of the marlin family, they’re 10 feet from tail to bill and are known by their large dorsal fin, which resembles the sail of a boat.

There are two species, the Atlantic sailfish and and Indo-Pacific sailfish. In the 1940s, scientists believed they could swim up to 67 miles-per-hour, but a 2015 study suggests this number was never accurate.

They believe they would top out at around 22 miles-per-hour, at most, and that they can’t sustain those speeds for prolonged periods of time. Like a cheetah, they have bursts of speed to allow them to hunt and catch prey, but most of the time, they’re “walking” at much slower speeds.

A 2015 project by the Central American Billfish Association claims to have recorded a tracked sailfish accelerating at a G-force of 1.79 G. If it was able to maintain that speed for only a few seconds, it would be the equivalent of 78 miles-per-hour.

The Large Pelagics Research Center countered this with a similar study on bluefin tuna, and found they can accelerate at 1.8 times the sailfish record – 3.27 G.

To be clear, these were just bursts of speed, and more study is needed to understand how long the fish maintain this activity – it might not even be for the 2 assumed seconds.

If you’re curious, the cheetah does take the land speed record among animals.

Sarah, a cheetah at the Cincinnati Zoo, was clocked at 61 miles-per-hour in 2012. She currently holds the recorded world record.

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