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Didymosphenia Geminata) Didymo (Didymosphenia Geminata

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Didymosphenia Geminata) Didymo (Didymosphenia Geminata Didymo (Didymosphenia geminata) Didymo (Didymosphenia geminata) Didymo (Didymosphenia geminata) Didymo (Didymosphenia geminata) 5 6 Hydrilla (Hydrilla verticillata) Hydrilla (Hydrilla verticillata) Native to: Northern regions of Europe (Faroe Islands, Sweden, Finland) and Introduced to: Chile Asia (Kanchou region of China) Also known as rockslide snot. 1 Didymo is a Didymo can survive2 outside of water freshwater diatom (type of algae) that in a damp cool environment for at uses a stalk to attach itself to rocks and least 40 days. Only one individual cell plants in rivers and streams. is needed to spread Didymo into a new water body. Introduced to: New Zealand Introduced to: South Dakota The original introduction pathway is The stalk material of Didymo forms unknown, but likely spread by thick mats that can completely cover transporting the plant3 material in substrate and take 4over the stream recreational gear (boats, fishing bottom smothering aquatic plants, equipment) and clothing (life jacket, insects and mollusks, reducing fish waders or boots). habitat and food. Introduced to: Florida Introduced to: California Boating, fishing, bait shipment, Hydrilla is named after the nine-headed irrigation and aquaculture are serpent of Greek mythology because it 5 secondary pathways6 that spread can grow a new plant from a tiny stem hydrilla. fragment. is slide 1 2 Hydrilla (Hydrilla verticillata) Hydrilla (Hydrilla verticillata) 3 4 Bullfrog (Lithobates catesbeiana) Bullfrog (Lithobates catesbeiana) 5 6 Bullfrog (Lithobates catesbeiana) Bullfrog (Lithobates catesbeiana) Afghanistan; Siberia; China; Japan HydrillaNative isto :a Asia popular (India, aquarium Korea) Introduced to: Washington and Australia plant. The dumping of household Hydrillaaquariums is a popular has introduced aquarium Hydrilla produces dense mats and Hydrillaplant. The to dumping aquatic of ecosystems household spreads rapidly, crowding2 out native throughoutaquariums has the introduced world.; HydrillaKorea; vegetation, reducing water quality, to aquatic ecosystems throughout disrupting the aquatic food chain and India; Nepal; Pakistan; Thailand; the world. ecology. Vietnam; Philippines), Australia and )slide 1 Introduced to: Western U.S. Native to: Central and eastern U.S. (including OR & WA) An aquatic frog that can be found in Introduced to Oregon in early 1900's streams, rivers, ditches,3 marshes, as a food item (frog4 legs). Also ponds, lakes and reservoirs. The introduced though aquarium trade, pet bullfrog prefers water with thick releases, intentionally stocked as a vegetation. biocontrol agent of insect pests and released accidentally during trout stocking. Introduced to: Cuba Introduced to: Jamaica Bullfrog prey on and/or compete Adults are voracious predators and with native frog species for food will consume anything that will fit in 5 and habitat. They6 can out- their mouth including: birds, rodents, reproduce native populations and frogs, snakes, crayfish, turtles, may transmit disease to native lizards, bats and their own young. species. is slide 1 2 Nutria (Myocastor coypus) Nutria (Myocastor coypus) 3 4 Nutria (Myocastor coypus) Nutria (Myocastor coypus) 5 6 Chinese mitten crab (Eriocheir sinensis) Chinese mitten crab (Eriocheir sinensis) Native to: Argentina Introduced to: Texas is nutria is a large semi-aquatic rodent that lives in colonies along The nutria is a large semi-aquatic Nutria can grow to 15-20 pounds rivers,rodent lakesthat lives and in wetlands. colonies along The and are opportunistic2 herbivores, wordrivers, "nutria" lakes and is Spanishwetlands. for The otter consuming roughly 25 percent of word "nutria" is Spanish1 for otter. their body weight in vegetation each day. Introduced to: Portland, OR Introduced to: Italy Nutria feeding habits can destroy Nutria were originally introduced native aquatic vegetation, crops and for fur production3 in 1889. When wetland areas. Nutria4 burrowing the fur market collapsed in the and riparian grazing cause 1940's, 1000's of nutria were streambank instability and erosion. released into the wild. They also are host to a variety of parasites and pathogens. Native to: South Korea Introduced to: England 5The mitten crab is named for the dense patches of hairs on its two The mitten crab was introduced The mitten crab is named for the through ballast water discharge densemitten patches crab is of named hairs on forits two the and/or intentionally6 as a food densefront claws.patches of hairs on its two source. front claws. claws. is slide 1 2 Chinese mitten crab (Eriocheir sinensis) Zebra mussel (Dreissena polymorpha) 3 4 Zebra mussel (Dreissena polymorpha) Zebra mussel (Dreissena polymorpha) 5 6 Zebra mussel (Dreissena polymorpha) Native to: Caspian Sea Introduced to: San Francisco Bay Zebrato: Caspian mussels areSea striped, this is fingernailslide 1 - Mitten crabs migrate2 in late spring, often sized mussels. They reproduce very long distances. They are adept quickly - females can produce walkers on land and will leave the water 40,000 eggs in one spawning and up to walk around barriers. to a million eggs annually. Introduced to: Lake Michigan Introduced to: Louisiana Zebra mussels were introduced to the Great Lakes as planktonic larvae Zebra mussels produce a strong in the ballast water3 of cargo ships. threadlike material 4called "byssal Other vectors of spread include threads". These threads enable them to aquarium dumping, transport of attach to many surfaces such as boat contaminated boats and recreational hulls or the shells of other animals. gear, fish stocking and aquaculture. Introduced to: Spain Zebra mussels have cost millions of 5 dollars in damage in6 areas where they clog facilities at power plants, water utilities, fish ladders, navigation locks and dams. is slide 1 2 New Zealand mudsnail New Zealand mudsnail (Potamopyrgus antipodarum) (Potamopyrgus antipodarum) 3 4 New Zealand mudsnail New Zealand mudsnail (Potamopyrgus antipodarum) (Potamopyrgus antipodarum) 5 6 Common carp (Cyprinus carpio) Common carp (Cyprinus carpio) Native to: New Zealand Introduced to: Australia The New Zealand mudsnail is a The New Zealand mudsnail is often tiny aquatic snailis slide (3-6 1 mm in introduced through2 ballast water length) that is adaptable to diverse discharge or the transport of live climatic and environmental fish or eggs for the commercial conditions. aquaculture industry. Introduced to: Idaho The IntroducedNew Zealand to: England mudsnail has a thick shell wall and rigid New Zealand mudsnail populations The New Zealand mudsnail has a thick in the United States are made up operculum that is used to seal off shell wall and rigid operculum that is entirely of females that reproduce 3 usedthe to shellseal off opening the shell which opening may by cloning themselves. A single whichallow may the allow snail the to snail pass to throughpass female has the reproductive through the digestive tract of predators potential to establish a new the digestive tract of predators alive and unharmed. population. alive and unharmed.4 Native to: Caspian Sea Introduced to: California The common carp is considered a nuisance species because of its tendency to destroy vegetation and The common carp was widely increase water turbidity5 by dislodging introduced as a food6 fish. plants and rooting around in the substrate. is slide 1 2 Common carp (Cyprinus carpio) 3 4 Purple loosestrife (Lythrum salicaria) Purple loosestrife (Lythrum salicaria) 5 6 Purple loosestrife (Lythrum salicaria) Purple loosestrife (Lythrum salicaria) Introduced to: Mexico is slide 1 The common carp2 is omnivorous feeding on aquatic plants, algae, insect/fish larvae, crustaceans, mollusks and even small fish. Native to: Europe and Asia Introduced to: Ethiopia Purple loosestrife is a highly Purple loosestrife is a tall, competitive plant that is capable of perennial herb with pretty purple 3 rapid growth and spread.4 Purple flowers that can be found in loosestrife displaces native plant wetlands, marshes, along river species, reduces biodiversity, and stream banks, pond edges, degrades wetland habitats and chokes reservoirs and ditches. irrigation channels and waterways. Introduced to: Australia Introduced to: Pennsylvania Purple loosestrife was brought to North America by settlers for Purple loosestrife is a popular medicinal purposes, for flower 5 ornamental plant. 6 Garden gardens, and in the ballast holds of horticulture has frequently European ships that used soil to introduced it to nearby natural areas. weigh down the vessels for stability in the ocean. is slide 1 2 Red swamp crayfish Red swamp crayfish (Procambarus clarkii) (Procambarus clarkii) 3 4 Red swamp crayfish Red swamp crayfish (Procambarus clarkii) (Procambarus clarkii) 5 6 Red-eared slider Red - eared slider (Trachemys scripta elegans) (Trachemys scripta elegans) Native to: Southeastern U.S. Introduced to: Kenya The red swamp crayfish is a large warmis -slidewater 1crayfish that 2 is most commonly found in slow Red swamp crayfish are dark red flowing rivers and streams, with raised, bright red spots marshes, lakes, reservoirs and covering the body and claws. irrigation systems. Introduced to: Japan Introduced to: Western U.S. (including OR & WA ) Red swamp crayfish may outcompete native crayfish for food The red swamp crayfish was introduced and habitat. Red3 swamp crayfish intentionally to create4 a food source. are also known to weaken stream Red swamp crayfish have also been banks through extensive burrowing, released from personal aquariums, leading to erosion
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