When I was at Andros South a couple weeks ago, one of the excellent guides on staff, Ellie, showed me something about a bonefish that I had never before noticed. I was getting ready to release another flawless Bahamian specimen that calls the flats of South Andros home and he told me to rub my finger over the fish’s eye. I did so and much to my surprise, I felt a slick case, almost like a lens of sort, covering the eye of the bonefish. This lens is transparent so it would be nearly impossible to notice without first feeling it but there was no doubt a thin case over it’s eye. After releasing the fish, Ellie explained why the bonefish had adapted such a trait.
As the bonefish feed, some of the time they will burrow their heads deep into the sand to chase down their prey. They have even been known to dredge down into the mud before blowing water out of their mouth to help expose shrimp and crustaceans (photo below). This clear lens serves as a case protecting their eyes as they dig into the sand. The lens starts thin near the nose of the bonefish before building to cover the eye, then smoothly tapers back down towards its gill. It allows protection to the eye of the fish without compromising the profile (aka speed) of the prized flats target. I have caught plenty of bonefish before but never knew about this cool adaptation until just weeks ago. Next time you have the privilege of holding a bonefish, be sure to check out its glasses!
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