The mixed topography of the refuge yields a wide variety of habitats for reptiles and amphibians, including vernal pools, calcareous fens, rocky woodland slopes, floodplain swamps, emergent marshes, small rocky streams, and open meadows. Consequently, the refuge supports a great diversity of reptiles and amphibians, including several species which are on Federal and State lists of rare and declining species. In fact, few areas in northern New Jersey support such a large concentration of species in need of protection. Also, the Refuge protects habitat in one of only two river drainages in New Jersey that is in the range of the blue-spotted salamander (Ambystoma laterale; state-listed endangered). Other listed species on the Refuge include eastern mud salamander (Pseudotriton montanus), longtail salamander (Eurycea longicauda), wood turtle (Clemmys insculpta; state-listed threatened), northern spring salamander (Gyrinophilus p. porphyriticus), spotted turtle (C. guttata), and eastern box turtle (Terrapene c. carolina; state-listed special concern).

The most abundant herptile species of the Refuge include northern redback salamander (Plethodon cinereus), northern two-lined salamander (Eurycea bislineata), northern spring peeper (Pseudacris c. crucifer), green frog (Rana clamitans melanota), common snapping turtle (Chelydra s. serpentina), eastern painted turtle (Chrysemys p. picta), northern water snake (Nerodia s. sipedon), and eastern garter snake (Thamnophis s. sirtalis).

The refuge is currently participating in three herpetology surveys: 1) a northeast regional anuran call count survey, 2) a vernal pool survey, and 3) an amphibian roadside crossing mortality survey. In the recent past, the refuge has participated in three other surveys: 1) streamside salamander survey, 2) malformed frog surveys, and 3) the recently concluded surveys for the NJ Herptile Atlas.

Since 2000, the refuge has participated in the regional anuran call count surveys. These are an effective way to determine species occurrence and abundance, the effects of management activities, and to evaluate the overall health of the habitat.

Beginning in 2001, the refuge has assisted the U.S. Geological Survey (USGS) Northeast Amphibian Research and Monitoring Initiative in the long term monitoring of streamside salamanders and vernal pool breeding amphibians. The objectives of this initiative are to determine the status and trends of amphibians in the Northeast for the ultimate goal of conserving amphibian populations and establishing a long term monitoring program on Department of the Interior lands.

There is concern that pesticides from agricultural operations or from mosquito control activities may be causing deformities in amphibians in the northern part of the country. In 1997 on two sites, and in 1998 on four sites, the refuge conducted preliminary surveys for frog abnormalities. In 1999, a comprehensive survey of four sites was conducted by the USFWS Chesapeake Bay Field Office. Based on the 1999 data, a follow-up survey was conducted in 2000. The results indicate that although frogs with abnormalities were found on the refuge, there was not enough evidence to suggest these levels were outside the range of natural variability. The study was concluded in this area (Eaton-Poole and Pickney, 2001).