Not all sharks can "blink."
Fish in general, do not have any kind of an eyelid, or nictitating membrane.
Not all sharks have eye protection called nictitating membranes. Of the 453 shark species worldwide, there are about 15 species that lack this eye protection.
Some species in New England coastal waters without a nictitating membrane are: the white, shortfin mako, porbeagle, thresher, sand tiger, dogfish, and basking shark.