Several species from the family Antherinidae are found in Cayman waters, although the hardhead silverside, Antherinomorus stipes dominates.
Four inches in length when fully mature, these fish will densely pack together in wrecks, caves, or deep-cut canyons, forming a seemingly impenetrable wall or mirror. It’s a great moment for divers who enter the ‘barrier’, which will part and then engulf them.
Occasionally, a large predator like a tarpon (seen in the image) will just miss you, heading in the opposite direction.
The real danger is bumping into a fat lionfish.
Tom Byrnes is the owner/operator of Cayman Marine Lab. He acquired his Coast Guard Captain’s Licence when he was a teenager and worked as a commercial fisherman in his youth. He got his first diving certificate in 1974 with the YMCA. He has worked in the local dive industry for more than 35 years and has a PhD in marine biology.