Staycation: John Heinz National Wildlife Refuge at Tinicum


When most Philadelphians think of their backyard, they don’t envision nearly 1,000 acres of unique habitat and diverse ecosystem, but thanks to the John Heinz National Wildlife Refuge at Tinicum, Philadelphians have just that – a public wildlife refuge right in their own backyard. 

The John Heinz National Wildlife Refuge at Tinicum is one of more than 500 National Wildlife Refuges in the United States.

While most major cities have a refuge within an hour’s drive, the John Heinz refuge is situated in Philadelphia and Delaware counties, making it the most urban refuge in the country. It is also home to the largest remaining freshwater tidal marsh in Pennsylvania, a 145-acre manmade pond and more than 300 bird species. 

Wildlife First

Managed by the United States Fish and Wildlife Service, the refuge puts wildlife first. Of the refuge’s 300-some bird species, more than 80, including bald eagles, nest within refuge boundaries. Because it is a major stop on the Atlantic Flyway, the route migratory birds travel along the East Coast, the cast of bird species changes throughout the seasons. In late summer, the refuge managers can regulate water levels to create mud flats where migrating birds can rest and feed mid-journey. 

With such abundance and variety of bird life, bird watching and photography are popular activities at the refuge. It is common for volunteers to watch the resident eagles and to point the birds and their nest out to curious visitors.

In addition to birds, the refuge is home to frogs, turtles and snakes, none of which are venomous. Among those are the Redbelly Turtle and Coastal Plain Leopard Frog, threatened species in Pennsylvania. 

Fishing is allowed along Darby Creek and in a few other areas. Some common catch include Hybrid Striper, Bluegill, Carp, Largemouth Bass, Channel Catfish and American Shad. Fish from all refuge waters were tested for pollutants in 1994. Some were found safe to eat, but the refuge recommends that none of the fish caught on the refuge be eaten. 

It is not uncommon to see groundhogs, fox, deer, rabbits and other mammals roaming the grounds as well. 

The Marsh

The crown jewel of the refuge is the more than 200-acre, freshwater tidal marsh – the largest remaining in Pennsylvania. 

Once as large as 6,000-acres, the marshland was home to the Lenape Indians, who called it Tennakon Minquas – meaning roughly “islands of the marsh.” When the European settlers arrived in the mid-1600s they began to farm the land. Dutch settlers drained and damned the marsh and others filled portions in to support the growing Philadelphia region. By the 1950s, the marsh had all but disappeared. It dwindled to just 200-acres. 

As serene and peaceful as the refuge is, it does have two especially noisy neighbors – the Philadelphia International Airport and I-95. In the ‘60s a proposal threatened to build I-95 through the last remaining portion of the marsh. Concerned citizens joined forces and with the help of Congress they were able to have the I-95 project rerouted. In 1972 the area officially became a national wildlife refuge. 

Today the marsh provides vital habitat for all of the critters mentioned above and plays a vital ecological roll. The marsh filters water as it leaves Darby Creek in Philadelphia and heads on to the Delaware River. 

“Everything that goes into Darby Creek ends up in the marsh,” said Deputy Refuge Manager Mariana Bergerson.

Water (and pollutants) from Cobbs Creek and the Delaware River also enters the marsh and make its water quality highly variable and complex. 


Ten miles of trails loop throughout the wildlife refuge and its various habitats. All trails are open to hikers and many are open to cyclists as well. The most popular trail is a three-mile loop that leaves the visitors center and crosses the manmade impoundment. The trails are open year-round. 

Boats are permitted in Darby Creek, and refuge staff recommend getting into and out of the river in the four-hour window around high tide (within two hours before high tide and two hours after high tide). On a typical day, the marsh can fluctuate as much as six feet. 

In 2001 the refuge opened the Cusano Environmental Education Center to better promote its education-based mission. A $2.5 million gift from the late Tony Cusano made the construction of this green, education and visitors center possible, and today, everywhere visitors turn there is something “green” to see and learn about.

The building, which was built on stilts to impact water flow around the building’s footprint as little as possible, uses solar power, geothermal heating and cooling, and countless recycled building materials. Floors are made of recycled tires. Recycled water bottles make up some of the decking and recycled chalkboards are mounted in the classrooms. An onsite “Marsh Machine” treats wastewater from the refuge’s sinks and toilets using plants and microorganisms just as the marsh outside filters water, and light up maps show the routes of migratory birds in the U.S. Other maps show just how drastically the marsh has shrunk since European settlers arrived.

Future: Growing Refuge amid Increasing Development

The refuge today covers 993 acres, but when acquisition of surrounding land is complete, the refuge will consist of 1,200 acres. 

One major concern of refuge staff is nearby development, especially given the close proximity of the Philadelphia International Airport and I-95. Bergerson and Refuge Manager Gary Stolz worry about talk of developing a currently untouched parcel of land in Philadelphia’s Eastwick neighborhood. PlanPhilly’s Kellie Patrick Gates has covered this development discussion in the past.

“The important thing is that it’s maintained as an open space,” Stolz said. “… As long as it’s protected, that’s our concern.”

What to know if you go:

  • Location: Main entrance at 86th Street and Lindbergh Boulevard
  • Hours: Sunrise to Sunset

For More Information:

Development in that current green space could threaten animals that have made the area their home, including the American Woodcock, an already threatened bird species. 

“Wildlife doesn’t know political boundaries… if [the wildlife] wander too far, they’re road kill,” Stolz said. 

One option might be turning the land into some sort of green connector for both wildlife and human life. The area in question could be used to build a trail between SEPTA’s Eastwick Station on the airport regional rail line and the visitor’s center. That connection would make accessing the refuge via public transit much easier. It is doable today, but it is not as easy as it could be, Bergerson said. 

With an easy connection between Eastwick Station and the refuge, Stolz said, “Everybody in Philly could come enjoy their own backyard.”

Heinz NWR map
Heinz NWR map

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