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During 1990-93, we measured demographic responses of black bears (Ursus americanus) in Shenandoah National Park, Virginia, to oak (Quercus spp.) mortality induced by infestations of gypsy moths (Lymantria dispar). We hypothesized that a reduction in the park's oak component and the subsequent acorn crop would negatively affect bear reproduction and survival. We compared the results to data collected in SNP from 1982 to 1985, before the gypsy moth infestation. Survival of all bears fitted with radiotransmitters (n = 36) was 100%, indicating that at least the female survival rate did not decline from a high pre-infestation survival rate of 95%. Minimum annual mortality (n = 61), based on eartag returns, was 4% (SE = 0.007). Mean litter size (n = 12) was 2.25 cubs (SE = 0.31) and did not differ (P = 0.49) from a pre-infestation mean of 2.0 cubs (n = 21 litters, SE = 0.17).