Animals

Birds

A total of at least 243 species of birds have been recently recorded within the George Washington Memorial Parkway. Some of the parkway's birding hotspots include Great Falls Park from which 35 species of warblers have been reported during the spring or fall migrations and Dyke Marsh which has at least 25 species of waterfowl and is one of the few places in the Washington DC area where you have a chance of finding Marsh Wrens, and American and Least Bitterns. Another popular birding spot is the large mudflat area at the mouth of Hunting Creek (just north of Dyke Marsh). Here you can find 28 species of Plovers, Sandpipers and other wading birds during spring and fall migrations.

Amphibians

Within the units of the George Washington Memorial Parkway are found the aquatic (streams, river banks, and vernal pools) and terrestial habitats needed by the 16 species of amphibians that have been identified here. These include seven species of frogs, Northern Cricket Frog (Acris crepitans), Spring Peeper (Pseudacris crucifer), Gray Tree Frog (Hyla versicolor/chrysoscelis), Bull Frog (Rana catesbeiana), Green Frog (Rana clamitans), Pickerel Frog (Rana palustris), and Wood Frog (Rana sylvatica), three species of toad, American Toad (Bufo americanus), Fowler's Toad (Bufo woodhousii fowleri), and Eastern Spadefoot Toad (Scaphiopus holbrookii), six species of salamander, Spotted Salamander (Ambystoma maculatum), Marbled Salamander (Ambystoma opacum), Northern Dusky Salamander (Desmognathus fuscus), Two-lined Salamander (Eurycea bislineata), Longtail Salamander (Eurycea longicauda), and Red-backed Salamander (Plethodon cinereus). The Eastern Spadefoot Toad was discovered in Great Falls Park in 2003 and other species of amphibians are expected to be found as search efforts increase.

Mollusks

Currently little is known of the mollusk species found in GWMP, however this group will be a focus of terrestrial and aquatic studies in Great Falls Park, Turkey Run Park and around Theodore Roosevelt Island in 2004 and 2005.

Animals

The George Washington Memorial Parkway (GWMP) provides habitat for the 245 species of birds, 24 mammals, 20 reptiles, 16 amphibians, 61 fish, 43 mollusks, 11 crustaceans, 76 butterflies, 722 moths, 466 beetles, 38 arachnids, 36 dragonflies and damselflies, and 28 caddisflies that have been documented as extant. Twenty-six species of animals (6 vertebrates and 20 invertebrates) are listed by the states of Virginia or Maryland as rare, threaten or endangered in the states where they occur. Additionally, 51 of the beetle species, 5 true bugs, 2 alderflies, a moth, a flower fly, a sawfly, and a bee, found within GWMP are not known from any other Virginia sites. Inventories of other taxonomic groups are currently underway at GWMP.

Reptiles

The woodlands, streams and riverbanks found within the units of the George Washington Memorial Parkway (GWMP) provide habitat for a total of 20 species of reptiles that live here. These include ten species of snakes, two species of skinks, and eight species of turtles.

The seven species of snakes known from GWMP are, Northern Brown Snake (Storeria dekayi), Northern Copperhead (Agkistrodon contortrix mokasen), Eastern Worm Snake (Carphophis a. amoenus), Northern Ringneck Snake (Diadophis punctatus edwardsi), Black Rat Snake (Elaphe obsoleta), Northern Watersnake (Nerodia sipedon), Rough Green Snake (Opheodrys aestivus), Eastern Hognose Snake (Heterodon platirhinos), Corn Snake (Elaphe guttata), and Eastern Garter Snake (Thamnophis s. sirtalis). Only one of these, the Northern Copperhead, is venomous. Northern Copperheads have been reported from Turkey Run and Great Falls Parks, where they are fairly common.

The two species of skinks known from GWMP are the Broadhead Skink (Eumeces laticeps) and the Five-lined Skink (Eumeces fasciatus). These two species can look quite similar at certain stages of there life cycles, however the Broadhead Skink matures at a larger size than that of the Five-lined Skink.

A total of seven species of native turtles and one non-native (introduced) species have been recorded from GWMP. The seven native species are Box Turtle (Terrapene carolina), Common Musk Turtle (Sternotherus odoratus), Eastern Painted Turtle (Chrysemys p. picta), Eastern Snapping Turtle (Chelydra s. serpentina), Red-bellied Turtle (Pseudemys rubiventris), Eastern Spiny Softshell (Apalone spinifera) and Wood Turtle (Clemmys insculpta). The feral, introduced, species is the Red-eared Slider (Trachemys scripta elegans). The Wood Turtle is known in GWMP from a single record from Great Falls Park in 1994 and a record from Turkey Run Park in 2005. The Eastern Spiny Softshell is known only from a 2006 record from Dyke Marsh. Both the Wood Turtle and Eastern Spiny Softshell are state listed (rare) species in Virginia. Any observations of Wood Turtles or the Eastern Spiny Softshell, or other species not listed here,  within GWMP should be reported to the park's Natural Resource Management Staff.

Crustaceans

Most of the crustacean inventories at GWMP have focused on amphipods, thus little is known of the other crustacean species that likely occur here. Six species of amphipod and one species of Caecidotea isopod have been documented from GWMP. One of the amphipods found within GWMP is a species new to science, currently known as Stygobromus sp. 15, until it is given a species epithet. The other five species of amphipods known from GWMP are Crangonyx shoemakeri, Gammarus fasciatus, Gammarus minus, Stygobromus pizzinii, and Stygobromus tenuis. A Grass Shrimp (Palaemonetes sp.) is occasionally found in Dyke Marsh. Eighteen species of copepod have been documented within GWMP. Two non-native crayfish, the Red Swamp Crayfish (Procambarus clarkii) and the Virile Crayfish (Orconectes virilis), and three native species, the Devil Crayfish (Cambarus diogenes), Appalachian Brook Crayfish (Cambarus bartonii) and Spiny-checked Crayfish (Orconectes limosus) have been found in streams and wetlands of GWMP.

Mammals

A total of 25 species of mammals have been recorded from GWMP. These include five species of bats, Big Brown Bat (Eptesicus fuscus), Eastern Pipistrelle (Pipistrellus subflavus), Little Brown Myotis (Myotis lucifugus), Silver-haired bat (Lasionycteris noctivagans) and Eastern Red Bat (Lasiurus borealis). Other mammals known to occur within GWMP are White-footed Mouse (Peromyscus leucopus), House Mouse (Mus musculus), Eastern Mole (Scalopus aquaticus), Northern Short-tailed Shrew (Blarina brevicauda), Southeastern Shrew (Sorex longirostris), Pine Vole (Microtus pinetorum), Norway Rat (Rattus norvegicus), Muskrat (Ondatra zibethica), Beaver (Castor canadensis), Eastern Chipmunk (Tamias striatus), Opossum (Didelphis marsupialis), Eastern Cottontail (Sylvilagus floridanus), Eastern Gray Squirrel (Sciurus carolinensis), Raccoon (Procyon lotor), Red Fox (Vulpes fulva), Gray Fox (Urocyon cinereoargenteus), Striped Skunk (Mephitis mephitis), Domestic Cat (Felis cattus), and Whitetail Deer (Odocoileus virginianus). The Allegheny Woodrat (Neotoma magister) was historically collected in Great Falls Park (1949), Turkey Run Park (1917), and Dyke Marsh (1897), but recent search effort (1998) did not reveal the presence of this species and it is believed to be extirpated within GWMP.

Insects, Spiders, Centipedes, Millipedes

This group undoubtedly represents the greatest amount of biodiversity found within the George Washington Memorial Parkway (GWMP) and is also the least known in terms of biological inventories. Currently, a total of 76 species of butterflies and 729 species of moths have been documented from GWMP. The only additional taxa that have been documented are 466 species of Coleoptera, 44 species of Diptera, 38 species of Arachnida, 38 Hymenoptera, 36 Odonata, 28 Trichoptera, 28 Heteroptera,  5 Homoptera, 4 Neuroptera,  2 Orthoptera, 1 Mecoptera, and 1 Plecoptera. Although no inventories of centipedes or millipedes have been conducted, funding is being sought to inventory these groups by 2010.

Fish

The Potomac River and its tributary streams within the George Washington Memorial Parkway (GWMP) are home to at least 61 species of fish (and one hybrid). Mine Run in Great Falls Park has the highest species richness of any stream in GWMP with 22 species recorded. Within GWMP, the Fallfish (Semotilus corporalis) and Longear Sunfish (Lepomis megalotis) are found only in Mine Run, the Swallowtail Shiner (Notropis procne), Fantail Darter (Etheostoma flabellare), Potomac Sculpin (Cottus girardi), and the Satinfin Shiner (Cyprinella analostana) are restricted to Turkey Run, and the Northern Hogsucker (Hypentelium nigricans) and Margined Madtom (Noturus insignis) are found only in Difficult Run. While on the Maryland side of GWMP the Sea Lamprey (Petromyzon marinus), Golden Redhorse (Moxostoma erythrurum) and Greenside Darter (Etheostoma blennioides) are known to occur only in Cabin John Creek. The American Eel (Anguilla rostrata) is found in more GWMP streams than any other species. Dyke Marsh, located along the Potomac River, is home to at least 38 species.