Adult discrimination ability and embryo performance was examined under different pH conditions in the eastern tiger salamander. Individuals from three populations were collected in habitats that differed naturally in pH. Two pH treatments were used to determine adult pH discrimination ability, and eight pH treatments to evaluate embryo performance. Results suggested that the pH of the source-population habitat could influence breeding-habitat discrimination by adults. Decreasing pH produced similar patterns of lethal and sublethal effects on embryos from the three populations, with reduced performance at low pH. The pH at which 50% mortality occurs was estimated at 4.2, suggesting that tiger salamanders were relatively acid tolerant. The study suggested that adult behavior patterns could influence the success of population reintroductions to previously acidified areas. 78 refs., 2 tabs., 4 figs.