That’s how shrimpfish roll
The fish go vertical but move horizontally
By Susan Milius
Shrimpfish swim forward standing on their heads. And that puts a rare spin on fishy turns.
Long, skinny Aeoliscus punctulatus mostly hang tails-up in the water with their mouths probing the seabed. But they aren’t just holding a pose, as upended trumpet fish do when hiding among sea grasses. The shrimpfish do most of their swimming horizontally in their vertical stance, sliding along the sand like pens in invisible hands.
“They’re absolutely bizarre fish,” says Frank Fish of West Chester University in Pennsylvania, who studies animals’ aquatic motions. A tank of shrimpfish caught his eye at a public aquarium in Eilat, Israel, near where he was on sabbatical in 2014. He and Roi Holzman of Tel Aviv University set up high-powered lights to take detailed video of the fish moves, becoming themselves objects of tourists’ curiosity.