HOLY MOLA: The ocean sunfish can grow to more than two meters in length, with a mass of up to 1,000 kilograms.© ISTOCK.COM/LEOPATRIZI
Off the coast of the French town Banyuls-sur-Mer, dozens of dorsal fins bob up and down in the water. A quick glance may suggest something menacing, but a longer look gives way to an even greater surprise: big, bizarre fish called Mola mola, from the Latin word for millstone. Commonly known as ocean sunfish, these behemoths tip the scales at up to 1,000 kilograms, making them one of the largest bony fishes alive today.
More intriguingly for the researchers who study them, some populations of ocean sunfish seem to be on the rise. “It’s quite striking in the western Mediterranean. I was there diving last spring and there were so many sunfish,” says David Grémillet, an expert on seabirds at the Center for Functional and ...