New Jersey Butterfly Sites

River Road Park and Robert J. Stahl Natural Area

by Mike Newlon

County: Somerset.

Municipality: Bedminster Township.

Directions: From I-287 South, take exit 22 for US 202/206 North. Stay to the right and in a hundred yards or so take the jughandle left turn at the first traffic light (River Road). Stay to the right on the jughandle and drive straight across US 202/206 on River Road. From I-287 North, take exit 22B for US 202/206 North and follow directions as above.
Once across US 202/206, turn right immediately into River Road Park, then left into a gravel parking area.

Parking: Yes, in addition to the River Road Park parking area described above, there is a smaller parking lot for the Robert Stahl Natural Area west 0.3 miles on River Road on the right.

Nearest sizable town: Pluckemin is a mile or so south on US 202/206; there is a large shopping center there. Gas stations and restaurants can also be reached to the north on US 202/206.

Habitats: Meadows, forest, two small ponds, a stream, North Branch of the Raritan River.

Maintained/Marked trails: Yes.

Restrooms: At least in the warmer months, there are portable toilets at River Road Park. To reach them, do not turn left into the gravel lot as described above but continue straight ahead through the stone gateposts, and turn right into a much larger parking area by athletic fields. The toilets are about halfway down the parking area. Currently there are no facilities at the parking lot west on River Road.

Picnic tables: No.

Species (notable in bold): Black Swallowtail, Eastern Tiger, Spicebush Swallowtail, Cabbage White, Orange Sulphur, Clouded Sulphur, Juniper Hairstreak, Gray Hairstreak, Red-banded Hairstreak, Eastern Tailed-Blue, Summer Azure, Great Spangled Fritillary, Pearl Crescent, Question Mark, Common Buckeye, American Lady, Painted Lady, Red-spotted Purple, Appalachian Brown, Little Wood-Satyr, Common Ringlet (once, unconfirmed), Common Wood-Nymph (can be abundant at the meadow-edge), Monarch, Silver-spotted Skipper, Southern Cloudywing, Horace’s Duskywing, Wild Indigo Duskywing, Swarthy Skipper, Least Skipper, European Skipper, Fiery Skipper (some years), Peck's Skipper, Tawny-edged Skipper, Northern Broken-Dash, Little Glassywing, Sachem (some years), Hobomok Skipper, Zabulon Skipper, Dun Skipper.

Best time to visit: Mid to late summer.

Exploring River Road Park and Stahl Natural Area: The large field to the west of the River Road Park parking area is good for Cabbage White, Sulfurs, Eastern Tailed-Blue, Swallowtails, Wild Indigo Duskywing, and European Skipper. However, there are no trails through this field. A better place to start butterflying is from the Robert Stahl Natural Area parking area 0.3 mile west from the River Road parking area. From the west end of the Stahl parking area, walk the unpaved road away from River Road, between two small ponds, up the rise to the Purple Martin houses. At the top of the rise, bear right until you come to a huge meadow. The best butterflying is often between the parking lot and the meadow. A trail runs all the way around the edge of the meadow. Midway down the north side, another trail runs north through woods and a small clearing; another trail branches west from this one, eventually reaching a small stream. On the south side of the meadow there is a stand of Red cedar. From the southeast corner of the large meadow, it is possible to return to the River Road Park lot, but this requires crossing an unbridged drainage ditch, which can be difficult after recent rains.

Across River Road from both parking area, trails lead through forest to the north branch of the Raritan River; butterflies are scarce on these.

Note: From the east end of the parking lot by the athletic fields (see Restrooms above) birders can cross US 202/206 on a pedestrian bridge to a trail that runs north parallel to the North Branch of the Raritan River (you can also go south but in my experience this area has not been too productive). One can bushwhack or use fisherman’s trails to get to the river’s edge. Eventually you reach a large pond on the left which attracts waterfowl in the cold months, although many of the waterfowl are Canada geese. Also from the east end of the athletic-field lot, it is possible to drive north to the Vandeveer House, a Revolutionary-War historic site. There is a large meadow here which looks attractive, but it is mowed so frequently that in my experience it does not produce much in the way of butterflies.

Special precautions: Take precautions against ticks if you walk off the trail into the fields. Also the area is heavily used by equestrians. Please be considerate, move off the trail, and do not disturb the horses.

You might also want to visit: Willowwood Arboretum and Bamboo Brook Outdoor Education Center.

Further information about Robert J. Stahl Natural Area is available

To view a larger map, click on 'View larger map' icon in upper right hand corner. (Tip: The satellite view may also suggest good potential butterfly habitat to explore.)

River Road Park sign

River Road Park sign.

River Road Park field

River Road Park field.

Stahl Natural Area sign

Stahl Natural Area sign.

Stahl Natural Area field

Stahl Natural Area field.