At a Glance

Access: Only by private boat at this time; this involves wading ashore from a boat moored off the State Park beach. No dockage is available.


  • Day Use, State Park Beach Area: 8 am – sunset; only registered campers after sunset. Beach area of State Park is open year-round for day use.
  • South Cell trails open Thursday through Monday, 8 am – 5 pm from May 1st – September 30th.
  • Camping available May 1st – September 30th.

Cost: Free for day-use; fee for overnight camping.

Tips: Bring scope, sunscreen, hat & other protective clothing. Bring all the food & drinks you will need in a backpack; even if the concession stand is open, it is not close to most of the birding area and offers limited choices. Especially in summer, bring ample water – there is extremely limited shade and it gets very hot.

Best Seasons: The South Cell of the State Park is only open from May 1 through September 30 and only Thursday though Monday during that season.

Breeding Bird Atlas Blocks: Middle River SE, Gunpowder Neck SW, Sparrows Point NE, Swan Point NW

Local MOS Chapter: Baltimore Bird Club

Hart-Miller Island State Park

In the Chesapeake Bay off Rocky Point Beach and Park, Essex, MD 21221
(410) 592-2897

Note: As of 2020, access to Hart-Miller Island has been limited to private boats; the previous visits via the official workboat were discontinued because of the COVID pandemic, but may resume in the future. See below “How to Visit.”.

Note: As of Spring 2022, the planned May 1st opening of the State Park has been delayed. MD DNR is working hard to upgrade the State Park restroom facilities on Hart-Miller Island; however, an unanticipated supply shortage is delaying completion until June 1, 2022. The Hart-Miller Island South Cell and campground will open as soon as this project is complete and the State Park is able to provide restroom amenities. The State Park staff apologize for the inconvenience and appreciate your understanding while they work to improve the facilities.​

Hart-Miller Island: you will either love it or hate it. Birders who know the island well find it a source of never-ending surprises, with ongoing habitat changes and rare birds tucked into hidden corners. Others come to the island and see only mud, water, and gravel roads, and dread a long walk around the perimeter.

In truth, Hart-Miller Island is one of the top five eBird hotspots in all of Maryland, with over 297 species reported on eBird, and 308 species on the official list maintained by the Maryland Ornithological Society (click here for the official checklist). With its placement in the upper Chesapeake Bay, at the mouths of Back River and Middle River in southeastern Baltimore County, Hart-Miller Island is well-positioned to host fall and spring migrating birds as well as summer breeders and overwintering birds. Hart-Miller is difficult for birders to access, but no guide to birding spots in Maryland would be complete without it.

Originally, Hart and Miller Islands, along with nearby Pleasure Island, were a chain of small islands historically used for duck hunting. But in the 20th century, the islands were eroding away, and their placement near the main shipping channel for the Port of Baltimore inspired an ambitious plan to connect Hart and Miller Island with a man-made dike, creating two impoundments to receive material dredged from the shipping channels that lead to the Port. The project is a partnership between the Maryland Port Administration, Maryland Environmental Service, and the US Army Corps of Engineers. Dike construction started in 1981; dredge placement began in 1984 and ended in 2009. At this time (spring 2022), management of the dredged material and creation of habitat in the North Cell still continues.

Today, the 1,140-acre island is shaped somewhat like a figure-eight: the large North Cell (not open to the public) occupies about 800 acres and the South Cell occupies about 300 acres.  The two cells are divided by a cross-dike, and each is circled by an outer dike. The cells are filled with dredged material and a varying amount of water. There are a couple of small but deep pits where soil has been removed for various projects, and these “borrow pits,” as they are known, are attractive to certain birds. The remnants of the original Hart and Miller Islands, accounting for a little over 200 acres, are on the northwestern and southwestern edges of the present-day island, and support two small stands of trees separated by a marsh.

The North Cell is still under construction and is closed to the public, but the South Cell has been deeded over to the Maryland Department of Natural Resources, and in 2016 opened to the public as part of Hart-Miller Island State Park. Visitors must provide their own boats; there are no public ferries or shuttle services. Private boats can moor off the beach; there are no docks available.

On the northwest side of the island, facing the mainland, the headquarters area of the State Park has a sandy beach with a primitive camping area, concession stand, and restrooms that are open May 1 through September 30. There are also a few primitive campsites on nearby Pleasure Island, which is part of the State Park. The South Cell is open for visitation from May 1 through September 30, Thursdays through Mondays from 8 am to 5 pm. The State Park staff has loaner binoculars and rents bicycles that can be used to ride around the South Cell, or it can be explored on foot.

The rim of the South Cell, which received dredged material from 1984 through 1990, has been extensively vegetated, and a nature trail with interpretive signage winds along the perimeter. The dike and nature trail allow viewing of an extensive grassland area as well as the open waters of the South Cell and the surrounding Chesapeake Bay. There is also a short trail through the woodland that borders the sandy beach and camping area, leading to an observation platform looking out over a natural marshland (good spot to try for rails), and there is a tall tower behind the park headquarters building that allows an extended viewing range. There is a small pine woods on the remnant of old Hart Island.

How to Visit:

Previously, through a cooperative arrangement with the Maryland Environmental Service (MES) and Maryland Port Administration, birders could ride the MES workboat to Hart-Miller for birding on designated days, but this option was discontinued during the COVID pandemic in 2020. The Maryland Environmental Service hopes to resume birding tours in the future, but we do not yet know when such tours will become available. MES will be advertising such tours through a private email list. To request that you be added to the email list to receive notices of upcoming Hart-Miller birding tours, send an email to with the subject line “Add me to mailing list.” This will place you on the mailing list for notification of birding tours to Hart-Miller as well as for Swan Creek/Cox Creek, another dredged materials site managed by MES.

At the present time, the only access to Hart-Miller Island is via private boat. The nearest public boat launch is at Rocky Point Park, owned by Baltimore County. At Hart-Miller, boat mooring is available off the State Park Beach. After wading ashore, visitors may take a trail through the woodland that adjoins the beach, or can take a path on top of the dike that circles the island’s South Cell. Such visits are only possible during the State Park season from May to September. It may be possible to rent a boat from a marina near Middle River or in the Miller’s Island residential community. Or, the Carefree Boat Club (private club with membership fee) on Middle River offers unlimited boat usage to members.

It is possible to kayak or canoe to the island, but this is not recommended for beginning paddlers due to strong currents and very busy boat traffic, and taking a scope by canoe or kayak is difficult. For those with their own canoe or kayak, the nearest launch site is at Rocky Point Park, but there is no soft launch, only concrete boat ramps. The paddling distance varies from 1.6 to 1.9 miles depending on which boat ramp is used at Rocky Point, and the route and distance will also depend on water and wind conditions.

Nearby, the Island View Waterfront Cafe rents kayaks. Another option is to join the Canton Kayak Club, which provides kayaks for member use. Canton Kayak Club has a dock location on the mainland on Island View Road that provides access to the Bay near Hart-Miller Island, but the club warns that the crossing to Hart-Miller should only be attempted by experienced paddlers, and many would say this paddling trip should only be done in a group for safety. The paddling distance from the Island View dock to Hart-Miller is just under 2 miles. The route is across open water with strong currents, no shelter from wind, and heavy boat traffic, so this should only be attempted by experienced paddlers.


Over 290 species have been reported on the eBird hotspot for Hart-Miller Island, but the official checklist maintained by the Maryland Ornithological Society lists 308 species, as of November 2021.  Click here for the official MOS checklist or here for a field checklist with spaces to mark the species you see.

Hart-Miller is best known for its vast assemblages of shorebirds during migration, with an astonishing 41 species reported on eBird. Breeding shorebirds have included Black-necked Stilt, Killdeer, and Spotted Sandpiper. Migrating shorebirds that are rarities or hard to find in Maryland can almost be expected on Hart-Miller; these include Whimbrel, Hudsonian Godwit, Marbled Godwit, Ruff, Curlew Sandpiper, Baird’s Sandpiper, White-rumped Sandpiper, Buff-breasted Sandpiper, and all three phalaropes.

Hart-Miller is also used by large flocks of gulls and terns, with 24 species reported. Notable rarities for the area have included Black-legged Kittiwake and Black-headed, Little, Franklin’s, California, Iceland, and Glaucous Gulls; Gull-billed, Black, Roseate, Arctic, and Sandwich Terns, as well as Black Skimmer. Lesser Black-backed Gulls are reliably found from May through October.

The island is also a prime overwintering spot for waterfowl. Thirty-three species of waterfowl have been reported on eBird, comprising almost all of the ducks, geese, and swans that regularly occur in eastern Maryland. Only Harlequin Duck and the eiders have not yet appeared at Hart-Miller. In 2021, a pair of Trumpeter Swans nested in Hart-Miller’s South Cell and fledged young; in 2022, it appears that the Trumpeters are again nesting.

All four regular grebes (Pied-billed, Horned, Eared, and Red-necked) can be found in appropriate seasons, with Pied-billed breeding on the island.  Both Common and Red-throated Loons can be found in the offshore waters, mostly from fall through spring. Both American White Pelican and Brown Pelican occasionally turn up and are becoming more frequent.

Among rails, Virginia Rail, Sora, and, in recent years, Common Gallinule breed on the island. If you are interested in herons, Great Blue Heron (year-round), Great Egret (April-October), and Snowy Egret (April-October) are easily seen; Black-crowned Night-Heron and Green Heron are also common; Little Blue Heron, Tricolored Heron, and Cattle Egret are less common but possible. Least Bittern, more often heard than seen, formerly bred on the island in large numbers, but with recent changes in habitat, their numbers may be reduced. American Bittern is sometimes found during migration.

A good set of raptors turns up at Hart-Miller. Osprey and Bald Eagle are breeders and are easily seen. Northern Harrier is also regular from August through May. Other regular raptors include Cooper’s, Sharp-shinned, Red-shouldered, and Red-tailed Hawks. Great Horned Owl has nested on the island; Short-eared Owl overwinters; and Snowy Owl is almost regular in winter, at least during irruption years. A pair of Peregrine Falcons nest on the nearby Craighill Channel Light, and often are seen, sometimes in extreme close-up views, chasing shorebirds and scattering the flocks. Merlin and American Kestrel are also easy to see.

The island is a great place to observe swallows, especially during migration, when there can be large flocks hunting over the impoundments. All of the expected Maryland swallows have been seen, including Cave and Cliff. As of 2022, it appears that a colony of Bank Swallows may beg attempting to nest in gravel and sand mounds.

The small woodlands hold a surprising variety of passerines, including the usual flycatchers, vireos, and other small birds. House Wren, Marsh Wren, and Carolina Wren all breed in numbers, and Winter Wren overwinters. Both Ruby-crowned and Golden-crowned Kinglets are common fall through spring. Wood Thrush and American Robin breed on the island, Hermit Thrush overwinters, and Swainson’s, Gray-cheeked, Bicknell’s, and Veery might be found during migration.

The grassland areas of the South Cell can be good for field birds, including American Pipit, Horned Lark, Lapland Longspur, Snow Bunting, Bobolink, and Eastern Meadowlark. About twenty species of sparrows have been reported; specialties include “Coastal Plain” Swamp Sparrow, which has bred on the island and is found year-round, and Savannah Sparrow, present in large numbers from fall through spring. Yellow-breasted Chat occasionally shows up from May through September, and Yellow-headed Blackbirds have been found during fall migration, along with the ever-present and numerous Red-Winged Blackbirds.

Thirty-four species of warblers have been reported, mostly migrants, but Common Yellowthroat and Yellow Warbler breed on the island, while Yellow-rumped overwinters in good numbers. Blue Grosbeak and Indigo Bunting are two more breeders on the island, easily seen from May through September.

Pet Policy:

Pets are not permitted on MES birding tours. For people arriving in their own boats, pets on leash are permitted in the State Park.

Wheelchair Access:

Hart-Miller Island is not accessible to wheelchairs.

Special Designations:

The entire island has been designated by the National Audubon Society as the Hart-Miller Island Important Bird Area.

The Northwest shoreline of Hart-Miller Island, including the remnants of Hart and Miller Islands and the State Park beach, lie within the Chesapeake Bay Critical Area; special laws regulate what kind of development can take place within the Critical Area.

Special Features:

An interesting history of Hart-Miller Island, written by DNR Seasonal Ranger Molly Hoopes, can be found in the MD DNR newsletter “Gunpowder Currents,” Fall-Winter 2016. ◾ For the official Maryland Ornithological Society checklist for Hart-Miller Island, click here. ◾ The State Park offers a seasonal concession stand, bicycle rental, picnic area, loaner binoculars and field guides, and primitive campsites. The island is popular for boating, fishing, offshore swimming, and waterfowl hunting.

The local chapter of the Maryland Ornithological Society is the Baltimore Bird Club, which offers field trips and meetings with speaker presentations, free and open to the public. The Baltimore Bird Club is the founding chapter of the Maryland Ornithological Society, and remains an important hub of birding activity in the state.


The Maryland Department of Natural History has posted two short YouTube videos in their “Virtual Ranger” series:

Both videos will give you a sense of the habitats and conditions on the island.


Depends on where your boat will leave the mainland. No cars on the island.


Hart-Miller Island is located off Rocky Point Beach and Park in Essex, MD. Because the island is only accessible by private boat, and these could be docked or launched at any number of places, it is not possible for us to provide directions.

Nearby Sites:

Baltimore City: Cylburn Arboretum ◾ Druid Hill Park ◾ Fort McHenry National Monument ◾ Masonville Cove Environmental Education Center ◾ Patterson Park

Baltimore County: Cromwell Valley Park ◾ Fort Howard Park ◾ Gunpowder Falls State Park – Hammerman Area & Dundee Creek Marina ◾ Hart-Miller Island State Park ◾ Holt Park ◾ Irvine Nature Center ◾ Lake RolandLiberty Reservoir Cooperative Wildlife Management Area – Baltimore County ◾ Loch Raven Reservoir Cooperative Wildlife Management Area ◾ Marshy Point Nature Center ◾ Milford Mill aka Villa Nova Park ◾ North Point State Park ◾ Northern Central Rail Trail (NCRT)Oregon Ridge Park ◾ Soldiers Delight Natural Environmental Area

Anne Arundel County: Downs Memorial ParkFort Smallwood ParkSwan Creek Wetlands | Cox Creek Dredged Material Containment Facility


ConifersUpland Deciduous Dredged Material Containment FacilityReclaimed Industrial Site Old Fields, Shrubby MeadowsSandy Beach or Dunes Forested SwampFreshwater Marsh or FloodplainJetties & SeawallsMud Flats (Tidal or Non-Tidal)Open Ocean, Bay, or Estuary


Bicycle Trails (Bikes may be prohibited on some trails)CampingFishingFree - No Entry Fee at Any TimeHabitat Restoration ProjectHiking/Walking TrailsNative Plant Garden or Meadow/Pollinator PlantsObservation Platform or TowerPets AllowedPicnic AreaRestroomsSnack Bar, Camp Store, Food ConcessionsSwimmingWater View


#1 Hotspot in County or CityAudubon Important Bird AreasChesapeake Bay Western ShoreState ParksThe Rivers of the Western Shore