What lives in the Delaware River?

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.



The Delaware River is a thriving ecosystem home to a diverse array of over 60 fish species, ranging from the iconic American shad to the endangered Atlantic sturgeon. The river serves as a critical migratory highway for "anadromous" fish that live in the ocean but spawn in fresh water. Beyond fish, the river supports a recovering population of North American river otters, beavers, and a variety of freshwater mussels which act as natural filters for the water. In the skies above, bald eagles and ospreys are common sights, having made a dramatic comeback in the region over the last few decades. In 2026, the river also hosts a growing number of "invasive" species that ecologists are closely monitoring, such as the northern snakehead and the blue catfish. The estuary portion of the river, where fresh and salt water mix, provides a unique habitat for blue crabs and diamondback terrapins, making the Delaware one of the most biologically significant waterways on the Atlantic coast.

People Also Ask

The Delaware River Basin has a very diverse ecosystem with a wide variety of wildlife. Eagles, bears, snakes, insects, beavers, otters, herons, Canadian geese, fish, eels, deer, and other animals can be found along the river banks.

MORE DETAILS

The Delaware River is known for freshwater populations of striped bass, muskellunge, brown trout, yellow perch, and American shad. When you visit New Jersey, be sure to plan a Delaware River fishing trip.

MORE DETAILS

Swimming in areas of the river outside the life guarded beaches is permitted, but not recommended. Strong currents, sharp drop-offs, and constantly changing river conditions make many areas unsafe for swimming. Wearing a properly fitting life jacket is strongly recommended when swimming. Never swim alone.

MORE DETAILS

Within the Upper Delaware Region, snakes are found in both terrestrial and aquatic habitats. Some snakes, like the Northern Watersnake, prefer aquatic habitats and are often found in slow-moving or standing water with places they can bask in the sun. The Northern Watersnake is commonly seen in and along the river.

MORE DETAILS

There are bull shark occasionally in the Delaware river. One was caught in a net in 1908 basically across the river from where the Philly Airport is today.

MORE DETAILS

For its size, the Upper Delaware River contains some of the highest water quality in the eastern United States. The upper portion of the watershed remains largely forested. These forests act as a natural buffer against pollution and erosion by filtering water, which is very important for maintaining water quality.

MORE DETAILS

However, the most famous fact about the Delaware River is the famous crossing of it by George Washington in 1776 which helped him successfully surprise Hessian troops in New Jersey during the American Revolution.

MORE DETAILS

Crocodiles and alligators, of course, are not native to the Delaware River, preferring much warmer climates. Some locals are theorizing that a local pet is on the loose.

MORE DETAILS

Fish consumption advisories issued in early 2018 show that the concentration of chemical contaminants in fish caught from Delaware waterways continues to decline – which indicates water quality is improving throughout the state and also means that fish caught in many Delaware waters can be eaten with lowered concerns ...

MORE DETAILS

The waters of the Inland Bays and Delaware Bay may contain organisms that could be harmful to one's health, particularly for persons with certain medical conditions or compromised immune systems. Swimming could result in an increased risk of rashes, infections or gastrointestinal distress.

MORE DETAILS