Delaware River Watershed-wide Focus Area
Delaware River. Photo courtesy of Wikipedia
The Delaware River, historically, appears to have had the largest spawning population of American shad in the United States. The population was dramatically reduced in early/mid 1900s due to a variety of factors including: over harvest, pollution, habitat destruction, blockage of rivers by dams, and entrainment/impingement on water-use facilities. With improvements in water quality due to sewage treatment and other factors, the population has been increasing since the 1970s. Shad is one of the most recreationally and economically important fish species in the river basin. Today, approximately 900,000 adult American Shad ascend the Delaware River each spring.
In addition to American shad, the Delaware River supports a wide diversity of migratory and resident fish populations that are important commercially, recreationally and ecologically. Examples of other migratory species include striped bass, American eel, and river herring. Resident species include smallmouth bass, channel catfish, walleye pike, hybrid muskellunge, white catfish, brown bullhead, white perch, sunfish, and suckers. Coldwater fisheries are supported in numerous creeks entering the river. The federally endangered Shortnose Sturgeon is concentrated in the estuary between Philadelphia and Trenton and is known to spawn in the Yardley and Lambertville areas. The globally rare Atlantic Sturgeon travels upriver as far as Trenton.
The free-flowing nature of the Delaware River is unique and exceptional. It flows through rolling hills and broad valleys; cliffs and palisades have emerged where the river has cut deeply into the rock. Rare plants cling to rock outcrops. On shelves of north-facing cliffs in Pennsylvania grow Arctic-Alpine plants such as Rosey sedum, while cacti dot the cliff shelves on the south-facing New Jersey side. In some areas sheer cliffs, rising to 400 feet above the valley floor, support special flora found at no other sites in the area. The Nockamixon Cliffs historically provided nesting sites for Peregrine Falcon. Bald Eagles use the river’s shoreline and islands for winter habitat.
Important reptile and amphibian species known to occur in or near the river corridor area include bog turtles, New Jersey chorus frogs, coastal plain leopard frogs, eastern mud turtles, and red-bellied turtles. The headwaters of the Rancocus Creek (a major tributary on the New Jersey side) were identified as a hotspot for rare bird species by the Gap Analysis Project. In addition, wetlands on the Pocono Plateau have been identified as important for bog turtle recovery. Indeed the Delaware Unit of the Bog Turtle Recovery Plan has broad overlap with the Delaware River Watershed.