We recorded the pattern morph for 9,950 frogs captured at nine locations in northeastern Puerto Rico over a 25-year period from 1978–2002. Data revealed 21 distinct pattern morphs including a variety of stripes, bars, and spots. Analysis of morph frequencies among plots showed significant differences, with longitudinal stripes more common in grassland and disturbed areas, and spot and bar morphs more common in forests where palm and bromeliad axils are important habitat features. Comparison of morph frequencies through time at the same sites showed temporal shifts immediately following Hurricane Hugo in 1989. We suggest that the pattern polymorphism is maintained in part by local habitat matching resulting from selection pressure from visual predators.