Friends of Dyke Marsh is a volunteer group dedicated to preserving, restoring and enhancing Dyke Marsh, a freshwater tidal marsh in Fairfax County on the Potomac River just south of Alexandria, Virginia. The Dyke Marsh Wildlife Preserve is administered by the National Park Service.

What Is Dyke Marsh?

The Dyke Marsh Wildlife Preserve is a freshwater, tidal marsh on the Virginia side of the Potomac River in Fairfax County. It is a unit of the George Washington Memorial Parkway, U.S. National Park Service. For more information, visit the NPS website at

Maryland Elementary Students Study Beetles and More in Dyke Marsh


Rising third graders from St. Philip the Apostle Catholic School, Camp Springs, Maryland, were intrigued by the black “patent leather” beetle or horned passalus (Odontotaenius disjunctus),  during their June 1, 2017, visit.  NPS Ranger Mireya Pasa urged the youngsters to touch the beetle and pointed out the insect’s distinctive mandibles. 

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More Native Plants and Trees Help Restore Dyke Marsh

Planting trees

On May 31, 2017, eight enthusiastic FODMers planted another 30 native shrubs and trees along the Haul Road trail east of the “dogleg” turn along the trail, led by NPS staffers Melissa Westbrook and Colin Davis.  This planting was in addition to the 40 plants put in on April 25, 2017. 

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Group Studies Biodiversity in Dyke Marsh

Spatterdock flower

On May 20, 2017, a class led by Joel Cohen, Audubon Naturalist Society, visited the Dyke Marsh Wildlife Preserve to study biodiversity.  A common wetland plant in the marsh, spatterdock (Nuphar polyspala), was in bloom, sporting its bright yellow, golf-ball-like flower.

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FODM at the Eagle Festival

FODM table

On May 20, 2017, FODM exhibited at the 20th annual Mason Neck Eagle Festival.  Glenda Booth and Marc Ribaudo, pictured here, staffed the table in the afternoon; Ned Stone and Trudi Hahn, in the morning.  A steady stream of youngsters made colorful birds at the FODM table and a “foxy” ranger visited.

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Periodic Cicadas Are Emerging


On May 14, 2017, FODMers saw periodic cicadas, genus Magicicada, emerging in Dyke Marsh, moreso in west Dyke Marsh, but definitely on both sides of the George Washington Memorial Parkway.  

Observers may see the insects’ shed nymphal skins at the base of trees. Unlike the cicadas that appear annually in Dyke Marsh (swamp, Robinson’s, Linne’s, scissor-grinder and others), the periodic cicadas appear much less frequently.

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Common Watersnakes Spotted


On May 14, 2017, FODMers observed several common or northern watersnakes (Nerodia sipedon sipedon) off both sides of the boardwalk.   These snakes are more active on sunny days than on cloudy days and are known to mate near the water's edge on logs, over rocks or on branches. Their coloration helps them camouflage, but movement in the cattails may give away their presence.

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Geology and Natural Communities, Focus of FODM Program

Tony Fleming

On May 10, 2017, Rod Simmons spoke to an enthusiastic audience of 60 and explored the geology of the Washington area and how it gives rise to diverse natural communities, calling the Washington-Baltimore region “the most geologically and floristically diverse area in the eastern United States.”  Rod is the Natural Resource Manager and Plant Ecologist for the city of Alexandria. 

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Bald Eagle’s Nest in Dyke Marsh

Bald eagle

There is one active bald eagle nest in the Dyke Marsh Wildlife Preserve this spring, 2017, confirmed by a National Park Service biologist’s helicopter survey conducted before trees leafed out.  Our fingers are crossed for some fledged young.  Bald eagles that hatch in April in this area usually can fly and leave the nest in early June. 

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Local Pre-schoolers Visit Dyke Marsh

St. Lukes

Forty pre-schoolers from St. Luke's Episcopal Church Day School, Mount Vernon area, visited the Dyke Marsh Wildlife Preserve on May 8, 2017, with their teachers.  The youngsters had a scavenger hunt and looked for birds, shells, gum balls, paw prints, cattails and critters. 

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D.C. Middle Schoolers Visit Dyke Marsh

Jackie Chicas

Thirty youngsters from Washington, D.C., Inspiring Connections, all students at Caesar Chavez Public Charter School for Public Policy and their three D.C. Sierra Club chaperones, learned all about freshwater wetlands and the flora and fauna of the Dyke Marsh Wildlife Preserve on April 29. 

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Planting Natives in Dyke Marsh

Melissa Westbrook

On a damp, overcast, 55-degree morning, eight volunteers and two National Park Service staffers planted 50 native shrubs and trees along the Haul Road in Dyke Marsh in the section of the wetland between the “dogleg” and the boardwalk.   Most of the plants are facultative, meaning edge plants or plants that grow in wetlands but can survive in non-wetlands.

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Raptors Enrapture Once Again

Red-tailed hawk

Despite gray skies and a steady drizzle, around 200 raptor fans -- young, old and in between -- enjoyed FODM’s annual Raptor Rapture on April 22, 2017, in Belle Haven Park.  Liz and Tim Dennison from Secret Gardens, Birds and Bees brought a red-tailed hawk (Buteo jamaicensis), a barred owl (Strix varia) and a great horned owl (Bubo virginianus), all “rescue birds.”

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