Bioremediation, through nutrient treatment, shows promise as a long-term in situ clean-up method for lightly and moderately oiled, sheltered (low-energy) shorelines that might be damaged by more intrusive measures, such as pressure washing. However, shoreline bioremediation has several misunderstood limits. Field research indicates that hydrocarbon-degrading microbes occur in all aquatic environments and that they reproduce greatly in the presence of oil: it is useless to add more. Wind, waves, currents, existing oil-degrading bacteria, nutrients, and oxygen are generally sufficient to promote maximum rates of degradation of oil. Under some circumstances, continuous or periodic application of nutrients (fertilizers) over a period of at least several weeks can accelerate oil degradation by factors of 1.5- to perhaps 5-fold. All future work should be done using statistically-robust sampling designs. In Japan, as elsewhere, there is great need for well-controlled, well-replicated, full-scale field tests to find out which, if any, bioremediation methods would be most useful for various oils, fuels and shoreline types. Intentional shoreline oiling and large-scale mesocosms facilities, coupled with well-tested treatment and monitoring protocols, are the best ay to conduct these tests.