Lichens are known to be sensitive to changes in air quality. The recent closure of a coal-fired electric generating plant in New Jersey has set up a natural experiment to study the potential rebound of nearby lichen communities. The study area is the Abbott Marshlands, an ecologically important freshwater tidal wetland along the Delaware River, much of which is protected open space. To establish a baseline for future study, a biodiversity inventory of lichens and allied fungi was undertaken in the Abbott Marshlands, yielding 57 species.