A recently described species of pupfish, Cyprinodon desquamator, was previously reported to have rapidly and sympatrically evolved lepidophagy (scale eating) on San Salvador Island, The Bahamas. Although lepidophagy is known from a variety of marine and freshwater fish species, the effects of this mode of predation on prey species have not previously been characterized. By examining scale regeneration rates in lakes with and without the scale-eating predator, we provide evidence suggesting that C. desquamator imposes high predation pressures on sympatric fishes, which supports the hypothesis that the feeding behavior of C. desquamator may have acted as an important driver of pupfish species divergence on San Salvador Island.