Resident species like smallmouth bass, channel catfish, hybrid muskellunge, bullhead, white perch, and walleye pike thrive in the river. The river's tributaries maintain stocked trout. Due to improving water quality, large schools of striped bass, shad and herring are again making their seasonal, upstream migration to their spawning areas. The federally listed endangered Shortnose Sturgeon can be found in river segments between Philadelphia and Lambertville, and the globally rare Atlantic Sturgeon swims as far upriver as Trenton. Other Rare species of (non-harmful) freshwater mussels and sponges grow in Tohickon Creek, PA, a stream of very high water quality.