The Jacques Cousteau National Estuarine Research Reserve, at Mullica River and Great Bay, is the only reserve in the national system to be named after an individual. It's also the only one in the reserve system to expand it boundaries seaward to the Atlantic Ocean.

In addition to the ocean environment, the reserve encompasses wetlands, riparian habitats, barrier islands and forested uplands of the New Jersey Pine Barrens. The area is regarded as one of the least disturbed estuaries in the densely populated urban corridor of the Northeastern United States.