The recovery of endangered fish species requires a careful evaluation of some key elements, such as abundance, size structure, and spatial distribution. Such evaluation usually involves comparing unfished areas with unprotected sites.
"But most such marine protected areas are too small and 'young' (established a few decades ago, at most) to provide information on 'pristine' conditions," Guidetti and colleague Fiorenza Micheli, a professor of marine ecology at Stanford's Hopkins Marine Station, wrote in the current issue of Frontiers in Ecology and the Environment.
To look farther back into the grouper's history, the researchers examined hundreds of Etruscan, Greek, and Roman paintings and mosaics depicting fishing scenes and fish.
At the end, they focused on 23 mosaics which represented groupers. In 10 of the 23 mosaics, dating from the 1st to 5th centuries, groupers were portrayed as being very large.
Indeed, the ancient Romans might have considered groupers some sort of "sea monsters" able to eat a fisherman whole, as shown in a 2nd century mosaic from the Bardo National Museum in Tunis.