The 80-acre (32 ha) refuge is composed of mature oak-hickory forest, a one-half-mile (0.80 km) rocky beach, a brackish pond, and several vernal ponds. The land and waters support a variety of songbirds (particularly warblers during spring migration), mammals, shorebirds, fish, reptiles and amphibians. During the colder months, diving ducks are common offshore, while harbor seals occasionally use the beach and nearby rocks as resting sites. New York State and federally protected piping plover, least tern, and common tern depend on the refuge's rocky shore for foraging and rearing young.
The spring bloom at Target Rock is a reminder of its days as a garden estate, with flowering rhododendrons and mountain laurel.