St. Mary’s County

St. Mary’s is one of the five counties within Maryland’s Southern Region, and occupies the south-most part of the region. In fact, St. Mary’s is the southernmost county on Maryland’s Western Shore. The county seat is Leonardtown, located in the middle of the county. The county is home to Patuxent River Naval Air Station (not open to the public) and St. Mary’s College of Maryland.

St. Mary’s County has 345+ species reported on eBird. For the county eBird checklist, eBird hotspots, and more, click here.

View a comparison of Maryland counties based on total number of species reported on eBird.

The county’s eastern border is formed by the Chesapeake Bay and the Patuxent River, Maryland’s longest river, and the western border is formed by the Potomac River. Adjoining counties are Calvert to the northeast; Charles to the north and west, across the Patuxent River; parts of Virginia to the west, across the Potomac River; and Dorchester County on the Eastern Shore, across the Chesapeake Bay. The border between St. Mary’s and Dorchester Counties is in the middle of the Bay.

St. Mary’s coastline has many coves, tidal creeks, bays and inlets. Many coastal areas are made up of mixed clay-and-sand cliffs and bluffs; however there are also low-lying coastal areas with coarse sand or gravel beaches or tidal marshlands. The county’s waters range from saltwater in tidal areas that are on or near the Chesapeake Bay, to brackish and freshwater in the interior tidal waterways. The interior of much of the county is hilly to varying degrees, with forests and agricultural fields. There are also coastal plain areas, much of which are also in agriculture or being developed for housing. The county is home to a thriving Amish and Mennonite farming community; check their farmyards for active Purple Martin and Tree Swallow colonies.

MD Routes 5 and 235 provide the main north-south corridors, and a large number of state routes criss-cross the county to reach the innumerable peninsulas and necks.

To view the State Highway Administration’s printable road map of St. Mary’s County (PDF format), please click here.

There is no chapter of the Maryland Ornithological Society centered in St. Mary’s County, but many birders participate in MOS through the Anne Arundel Bird Club or the Patuxent Bird Club; both of these MOS chapters offer field trips and meetings with informative programs, all free and open to the public. In addition, the Southern MD Audubon Society serves birders in Charles, Calvert, St. Mary’s and Prince George’s Counties.

Explore birding sites in St. Mary’s County by choosing from the list below.