Pompano Beach, Florida–Reportedly, a softball-size eyeball was discovered on the sandy beach in Pompano Beach, Florida last Wednesday according to a CNN report. At first investigators say that the big blue eyeball was cut out of a squid. But expert examination revealed that the eyeball came from a half-ton swordfish.
According to a statement from Joan Herrera, curator of collections at the agency’s Fish and Wildlife Research Institute in St. Petersburg, its size (softball), color (blue) and structure (presumably swordfishy) produced the final determination.
Based on straight cuts on the bone around the eyeball, Herrera said, experts think an angler cut it out of a swordfish and tossed it overboard. The half-ton fish are frequently found in the Florida Straits off South Florida at this time of year, according to the statement. DNA testing is being done to confirm the finding, the agency said.
There is however, another reason one might find the eye of a swordfish in sand close to a large ocean.
First of all, it’s important to point out that the eye of a swordfish can be diameters of up to 90 mm; in other words 3.54 inches in diameter. So a solfball-size eye is about the largest an eye of these species will get.
Swordfish, along with some species of shark, have special organs next to their eyes to heat their eyes and brain. Temperatures of 10 to 15 °C above the surrounding water temperature have been measured. The heating of the eyes greatly improves their vision, and consequently improves their ability to catch prey. Out of the 25,000+ fish species, only 22 are known to have a mechanism to produce heat. These include the swordfish, marlin, tuna and some sharks.
Depending on diving depth, temporal resolution can be more than ten times greater in these fishes than in fishes with eyes at the same temperature as the surrounding water. The enhanced temporal resolution allowed by heated eyes provides warm-blooded and highly visual oceanic predators, such as swordfishes, tunas, and sharks, with a crucial advantage over their agile, cold-blooded prey.
Although there are no reports of unprovoked attacks on humans, swordfish can be very dangerous when harpooned. These sea creatures are vigorous, and powerful fighters. When hooked or harpooned, they have been known to dive so quickly that they have impaled their swords into the ocean bottom up to their own eyes. This therefore is another possibility as to why one might find the eye of a swordfish on a sandy beach in Florida. Although there are no reports of unprovoked attacks on humans, swordfish can be very dangerous when harpooned.
Contributor D. Chandler
Contributor D. Chandler