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Sediment, mummichogs Fundulus heteroclitus, and fiddler crabs Uca pugnax were collected from 25 locations in and adjacent to Cape May National Wildlife Refuge NWR, Cape May County, New Jersey to determine baseline contaminant levels and to identify potential contaminant sources requiring further study. Mummichogs and sediments from all major drainages and selected tidal creeks were analyzed for trace metals and organochlorines pesticides and polychlorinated biphenyls, whereas fiddler crabs were analyzed for organochlorines only. None of the twenty organochlorines considered in this study were detected in sediments average detection limit 0.04 ppm dry weight. Trace metal concentrations observed in Cape May NWR sediments were considered to be typical for sediments in southern New Jersey and are probably representative of sitespecific background levels. Although low, concentrations of arsenic, beryllium, cadmium, chromium, copper, iron, lead, mercury, nickel, and zinc at one or more locations exceeded sediment effects rangelow ERLs, developed for estuarine sediments by the National Oceanic and Atmospheric Administration NOAA, and lowest effects levels LEs developed for freshwater sediments by Ontario Ministry of the Environment, Ontario, Canada. Because more severe effects levels e.g., effects rangemedians were not exceeded, it was concluded that the likelihood of adverse effects in benthic organisms exposed to contaminants at the observed concentrations is low to nonexistent. All trace metals appeared to be enriched, relative to iron or aluminum, in sediments from the uppermost reaches of the major drainages. It was not possible to determine whether the elevated levels are evidence of local anthropogenic inputs or heterogeneity in environmental factors e.g., percent total organic carbon. Further studies are recommended in these areas to determine the relative roles of environmental factors versus anthropogenic influences on sediment contaminant concentrations. Mean trace metal concentrations in mummichogs and fiddler crabs are at the low end of ranges typically observed in New Jersey. In addition, the maximum observed concentrations appear to be well below levels of concern for fish and wildlife. The only organochlorines detected in Cape May NWR biota were the DDT breakdown products, DDD and DDE. Average combined DDD and DDE tissue concentrations were comparable to background for the state. Maximum combined concentrations 0.18 ppm wet weight in mummichogs and 1.04 ppm wet weight in fiddler crabs, however, were greater than background. Although low, concentrations of DDE and DDD do not appear to have declined significantly since 1989. Although the use of parent compound DDT has ceased, the possibility remains that weathered material continues to enter the estuarine ecosystem as previously contaminated areas are disturbed by activities such as excavation or dredging. Organochlorine concentrations in Cape May mummichogs and fiddler crabs are low and are not expected to adversely affect the organisms themselves or their immediate predators. Further monitoring studies of DDD and DDE in forage organisms are recommended to better characterize temporal trends. In addition, studies on tissue DDE and DDD concentrations in midtrophiclevel organisms are recommended to better ascertain food chain transfer and dietary exposure of upper level predators to these compounds.