Mount Calvert Historical and Archaeological Park is part of the Patuxent River Park system and is managed by the Prince George’s County Parks and Recreation Department/Maryland-National Capital Park and Planning Commission. Mount Calvert is worth a visit for the spectacular view of the Patuxent River and its marshes at the north end of Jug Bay. During most of the year, these marshes are filled with birds. The marshes hold one of the largest stands of native wild rice on the East Coast; the wild rice is an important food for birds migrating through the area in the fall, and also offers nesting habitat for a number of species.
Mount Calvert is on the western shore of the Patuxent River, perched high on a point of land where the Western Branch flows into the main channel of the river, providing a panoramic view of the river and the head of Jug Bay. The northwest boundary of the park property roughly follows Charles Branch, which is a tributary of Western Branch. Across the marshes to the north is another historic property, Billingsley House, which sits on a prominent knoll and has been a landmark for boaters on the river for 300 years or more. Directly across the Patuxent River is the Jug Bay Wetlands Sanctuary of Anne Arundel County, and to the south on the Prince George’s side of the river is the Jug Bay Natural Area of Patuxent River Park. See the overview map of Jug Bay area parks at the link at left. The entire area is a birder’s Mecca, where you can happily spend days wandering through the many preserved tracts of land or exploring the Patuxent and its tributaries by boat.
The eBird list for Mount Calvert has over 190 species, quite a diversity for a medium-sized site – only about 189 acres, including the main parcel near the house, plus the woods and marsh to the west, near the Charles Branch of the Patuxent River. The compact size of the site means it can be thoroughly birded in an hour or two.
To reach Mount Calvert, simply follow Mount Calvert Road to its end at the property. A short gravel driveway leads from the entrance gate to the house area. Where the entrance road makes a sharp curve to the left, pull over to the side to take in the view across the river and marshes. If there are many birds on the water, you can set up your scope here. Or continue down the entrance drive to park in a designated grassy area under the shade of old trees, where the resident Northern Mockingbird will greet you. Check the trees around the parking area for warblers and flycatchers in spring and early summer. The electric wires along the entrance road are a favored gathering spot for swallows and martins in summer.
A gravel road (foot traffic only) continues past the house down to the water’s edge, where a wharf formerly provided a loading area for tobacco being shipped out by barge. The wharf area is now a soft launch for canoes and kayaks, and a short floating pier provides a good vantage point for birding. This is a good spot to set up your scope and to listen for Marsh Wrens and Sora. Osprey nest on platforms all through the marsh, and there are several Bald Eagle nests in the vicinity. The strip of trees bordering the lane down to the pier are a magnet of songbirds such as Baltimore Oriole, Orchard Oriole, Brown Thrasher, and Common Yellowthroat. The grassy edge of the lane attracts sparrows in fall and winter, including Savannah, Field, and sometimes a White-crowned.
The large fields along the entrance drive are planted with agricultural crops that vary from year to year. The crop fields provide good habitat for a variety of field birds that changes depending on season: American Pipits, Horned Larks, Savannah Sparrows, Field Sparrows, Eastern Meadowlarks, perhaps a few Bobolinks during migration. There are dirt roads through the fields and mown strips around the edges, and it is permissible to walk there, but driving in the fields is not allowed. If there are newly planted crops, be careful to stay on the lane and do not trample the crops.
Once you’re done scoping the river and marshes and exploring the fields and hedgerows, you can return in your car to the entrance gate; just outside the gate is a small parking area, with room fo two or three cars, outside a gated trail that heads north. This foot trail runs along the bed of a historic railroad (the rails and ties are long gone) that carried tourists from Washington, DC to Chesapeake Beach in Calvert County. The railroad bed trail runs in a straight line to the Charles Branch of the Patuxent River, a one-way distance under a half-mile, passing between hedgerows and woods edges that offer excellent habitat for songbirds. This is a good spot to check for Summer Tanagers in spring and summer. Carry your scope with you, because near the trail’s end at Charles Branch (no bridge, and impassable on foot), there are freshwater marshes to the left and to the right that may have waterfowl in winter and shorebirds, particularly snipe and yellowlegs, during migration. Wood Ducks and possibly Hooded Mergansers nest here. There are one or more Bald Eagle nests in the area, so be alert and check the tops of the largest trees.
Although birders are drawn to the habitat, others visit for the history. Mount Calvert was an important tobacco plantation in the 18th and 19th centuries, and was the site of the first county seat of Prince George’s County, from 1696 to 1721. The existing brick plantation house was built in 1796, with additional construction in 1809. Today the house is a museum with exhibits concerning the intertwined local history of tobacco growing, slavery, and pre-colonial Native American settlements. The area also saw significant activity in the War of 1812, when invading British warships came up the river, and this is documented in outdoor placards near the house. There are active archaeological excavations underway to uncover more of the history of the site.