Rare Species by County: Bristol
Last Updated on 3/1/2003
| Taxonomic Group | Scientific Name | Common Name | State Rank | Federal Rank | Most Recent Obs |
| Fish | Acipenser oxyrinchus | Atlantic Sturgeon | E | (LT,C) | 1992 |
| Fish | Lampetra appendix | American Brook Lamprey | T | 1982 | |
| Fish | Notropis bifrenatus | Bridle Shiner | SC | 1999 | |
| Amphibian | Ambystoma jeffersonianum | Jefferson Salamander | SC | 1983 | |
| Amphibian | Ambystoma laterale | Blue-Spotted Salamander | SC | 1999 | |
| Amphibian | Ambystoma opacum | Marbled Salamander | T | 2001 | |
| Amphibian | Hemidactylium scutatum | Four-Toed Salamander | SC | 2000 | |
| Amphibian | Scaphiopus holbrookii | Eastern Spadefoot | T | 1994 | |
| Reptile | Carphophis amoenus | Eastern Worm Snake | T | 18-- | |
| Reptile | Clemmys guttata | Spotted Turtle | SC | 2001 | |
| Reptile | Clemmys insculpta | Wood Turtle | SC | 1997 | |
| Reptile | Emydoidea blandingii | Blanding's Turtle | T | 2000 | |
| Reptile | Malaclemys terrapin | Diamondback Terrapin | T | 2000 | |
| Reptile | Terrapene carolina | Eastern Box Turtle | SC | 2000 | |
| Bird | Accipiter striatus | Sharp-Shinned Hawk | SC | (PS) | 1924 |
| Bird | Ammodramus savannarum | Grasshopper Sparrow | T | (PS) | 1993 |
| Bird | Asio flammeus | Short-Eared Owl | E | 1938 | |
| Bird | Botaurus lentiginosus | American Bittern | E | 1993 | |
| Bird | Charadrius melodus | Piping Plover | T | (LE,LT) | 1996 |
| Bird | Circus cyaneus | Northern Harrier | T | 1987 | |
| Bird | Falco peregrinus | Peregrine Falcon | E | (PS:LE) | 1996 |
| Bird | Ixobrychus exilis | Least Bittern | E | 1993 | |
| Bird | Parula americana | Northern Parula | T | 1880 | |
| Bird | Rallus elegans | King Rail | T | 1988 | |
| Bird | Sterna antillarum | Least Tern | SC | (PS:LE) | 1998 |
| Bird | Sterna hirundo | Common Tern | SC | 1998 | |
| Bird | Sterna paradisaea | Arctic Tern | SC | 1897 | |
| Bird | Tyto alba | Barn Owl | SC | 1987 | |
| Mussel | Alasmidonta heterodon | Dwarf Wedgemussel | E | LE | 1969 |
| Mussel | Alasmidonta undulata | Triangle Floater | SC | 2001 | |
| Mussel | Alasmidonta varicosa | Brook Floater (Swollen Wedgemussel) | E | ||
| Mussel | Leptodea ochracea | Tidewater Mucket | SC | 1999 | |
| Mussel | Ligumia nasuta | Eastern Pondmussel | SC | 2002 | |
| Mussel | Strophitus undulatus | Creeper | SC | 1984 | |
| Crustacean | Crangonyx aberrans | Mystic Valley Amphipod | SC | 1999 | |
| Crustacean | Eubranchipus intricatus | Intricate Fairy Shrimp | SC | 1994 | |
| Crustacean | Limnadia lenticularis | American Clam Shrimp | SC | 1985 | |
| Crustacean | Synurella chamberlaini | Coastal Swamp Amphipod | SC | 2001 | |
| Dragonfly/Damselfly | Anax longipes | Comet Darner | SC | 1994 | |
| Dragonfly/Damselfly | Enallagma daeckii | Attenuated Bluet | SC | 1994 | |
| Dragonfly/Damselfly | Enallagma laterale | New England Bluet | SC | 1999 | |
| Dragonfly/Damselfly | Enallagma recurvatum | Pine Barrens Bluet | T | 1993 | |
| Beetle | Cicindela duodecimguttata | Twelve-Spotted Tiger Beetle | SC | 1914 | |
| Beetle | Cicindela purpurea | Purple Tiger Beetle | SC | 1913 | |
| Beetle | Desmocerus palliatus | Elderberry Long-Horned Beetle | SC | 1936 | |
| Butterfly/Moth | Abagrotis nefascia benjamini | Coastal Heathland Cutworm | SC | 1987 | |
| Butterfly/Moth | Bagisara rectifascia | Straight Lined Mallow Moth | SC | 1987 | |
| Butterfly/Moth | Callophrys hesseli | Hessel's Hairstreak | SC | 1988 | |
| Butterfly/Moth | Cingilia catenaria | Chain Dot Geometer | SC | 1999 | |
| Butterfly/Moth | Eacles imperialis | Imperial Moth | T | 1986 | |
| Butterfly/Moth | Erynnis persius persius | Persius Duskywing | E | 1949 | |
| Butterfly/Moth | Hemileuca maia | Barrens Buckmoth | SC | 1986 | |
| Butterfly/Moth | Lithophane viridipallens | Pale Green Pinion Moth | SC | 1993 | |
| Butterfly/Moth | Papaipema stenocelis | Chain Fern Borer Moth | T | 1988 | |
| Butterfly/Moth | Papaipema sulphurata | Water-Willow Stem Borer | T | 1994 | |
| Butterfly/Moth | Spartiniphaga inops | Spartina Borer Moth | SC | 1994 | |
| Vascular Plant | Arabis missouriensis | Green Rock-Cress | T | 1998 | |
| Vascular Plant | Aristida purpurascens | Purple Needlegrass | T | 1955 | |
| Vascular Plant | Asclepias verticillata | Linear-Leaved Milkweed | T | 1904 | |
| Vascular Plant | Bidens eatonii | Eaton's Beggar-Ticks | E | 1984 | |
| Vascular Plant | Cardamine longii | Long's Bitter-Cress | E | 2000 | |
| Vascular Plant | Carex oligosperma | Few-Fruited Sedge | E | 1997 | |
| Vascular Plant | Carex polymorpha | Variable Sedge | E | 1908 | |
| Vascular Plant | Carex typhina | Cat-Tail Sedge | T | 2000 | |
| Vascular Plant | Claytonia virginica | Narrow-Leaved Spring Beauty | E | ||
| Vascular Plant | Crassula aquatica | Pygmyweed | T | 1905 | |
| Vascular Plant | Dichanthelium mattamuskeetense | Mattamuskeet Panic-Grass | E | 1990 | |
| Vascular Plant | Eleocharis microcarpa | Tiny-Fruited Spike-Sedge | E | 1998 | |
| Vascular Plant | Eleocharis tricostata | Three-Angled Spike-Sedge | E | 1995 | |
| Vascular Plant | Eupatorium aromaticum | Lesser Snakeroot | E | 1903 | |
| Vascular Plant | Gamochaeta purpurea | Purple Cudweed | E | 1889 | |
| Vascular Plant | Helianthemum dumosum | Bushy Rockrose | SC | 1989 | |
| Vascular Plant | Hydrocotyle verticillata | Saltpond Pennywort | T | 18-- | |
| Vascular Plant | Juncus debilis | Weak Rush | E | 1999 | |
| Vascular Plant | Lechea pulchella var moniliformis | Bead Pinweed | E | 1910 | |
| Vascular Plant | Liatris borealis | New England Blazing Star | SC | 2000 | |
| Vascular Plant | Linum medium var texanum | Rigid Flax | T | 1999 | |
| Vascular Plant | Listera cordata | Heartleaf Twayblade | E | ||
| Vascular Plant | Ludwigia sphaerocarpa | Round-Fruited False-Loosestrife | E | 1913 | |
| Vascular Plant | Lycopus rubellus | Gypsywort | E | 2000 | |
| Vascular Plant | Lygodium palmatum | Climbing Fern | SC | 1998 | |
| Vascular Plant | Myriophyllum pinnatum | Pinnate Water-Milfoil | SC | 1983 | |
| Vascular Plant | Ophioglossum pusillum | Adder's-Tongue Fern | T | 1900 | |
| Vascular Plant | Oxalis violacea | Violet Wood-Sorrel | E | 1889 | |
| Vascular Plant | Panicum philadelphicum | Philadelphia Panic-Grass | SC | 1999 | |
| Vascular Plant | Panicum rigidulum var. Pubescens | Long-Leaved Panic-Grass | T | 1999 | |
| Vascular Plant | Platanthera cristata | Crested Fringed Orchis | E | 1988 | |
| Vascular Plant | Platanthera flava var herbiola | Pale Green Orchis | T | 1990 | |
| Vascular Plant | Podostemum ceratophyllum | Threadfoot | SC | 2002 | |
| Vascular Plant | Polygonum glaucum | Sea-Beach Knotweed | SC | 1989 | |
| Vascular Plant | Prenanthes serpentaria | Lion's Foot | E | 1929 | |
| Vascular Plant | Ranunculus micranthus | Tiny-Flowered Buttercup | E | 1988 | |
| Vascular Plant | Rotala ramosior | Toothcup | E | 1930 | |
| Vascular Plant | Sabatia kennedyana | Plymouth Gentian | SC | 2000 | |
| Vascular Plant | Sabatia stellaris | Sea Pink | E | 1988 | |
| Vascular Plant | Sagittaria subulata var subulata | River Arrowhead | E | 1998 | |
| Vascular Plant | Sanicula canadensis | Canadian Sanicle | T | 1998 | |
| Vascular Plant | Scirpus longii | Long's Bulrush | T | 1998 | |
| Vascular Plant | Scleria triglomerata | Tall Nut-Sedge | E | 1888 | |
| Vascular Plant | Setaria geniculata | Bristly Foxtail | SC | 1999 | |
| Vascular Plant | Spartina cynosuroides | Salt Reedgrass | T | 1998 | |
| Vascular Plant | Sphenopholis pensylvanica | Swamp Oats | T | 1989 | |
| Vascular Plant | Spiranthes vernalis | Grass-Leaved Ladies'-Tresses | T | 1986 | |
| Vascular Plant | Suaeda calceoliformis | American Sea-Blite | SC | 1909 | |
| Vascular Plant | Triosteum perfoliatum | Broad Tinker's-Weed | E | 1901 | |
| Vascular Plant | Tripsacum dactyloides | Northern Gama-Grass | E | 2000 | |
| Vascular Plant | Viola brittoniana | Britton's Violet | T | 1916 |