Transcript Slide 1
Zebra Mussels (Dreissena polymorpha) Native to: the Caspian Sea region of Asia Invasive in: the Great Lakes, USA. They were first observed in Lake St. Clair near Detroit in 1988, and spread quickly. Transported by: ballast water Zebra Mussels (Dreissena polymorpha) Impacts: • deplete the food supply needed by larval and juvenile fishes (this affects fisheries too!) Zebra mussels on a dragonhunter larva (above). Pipe clogged by zebra mussel growth (below). • attach themselves to native mussels, making those mussels more vulnerable to stress • clog pipes • clog cooling water inlets in boats, causing them to overheat • take in a lot of chemicals in the water, which builds up in their bodies and is transferred to any animals that eat them European Rabbit (Oryctolagus cuniculus) Native to: the Iberian Peninsula in the Mediterranean Invasive in: Australia. They were first brought over in 1788, they were introduced to the wild in 1859, and there were additional introductions in the late 1800s. Transported by: people bringing them over as pets European Rabbit (Oryctolagus cuniculus) Impacts: Phillip Island when European rabbits were abundant (above) and after they were removed from the habitat (below). • compete with local fauna for food and shelter • damage soils, causing erosion problems • overgraze by killing mature plants and suppressing recruitment of seedlings • caused a decline in the bilby (Macrotis lagotis) population • caused the burrowing bettong (Bettongia lesueur) to disappear in the Northern territory Burrowing Bettong Control: in the early 1950s, Myxomatosis, a fatal disease only affecting rabbits, was introduced to Australia to help prevent the spread of the European rabbit. Giant Salvinia (Salvinia molesta) Native to: southeast Brazil Invasive in: Australia, New Zealand, and parts of America Transported by: people bringing them over to be used in aquariums and garden ponds Giant Salvinia (Salvinia molesta) Impacts: • create floating mats 10-20 cm (up to 60 cm!) thick • block sunlight to other species • clog waterways Waterway covered in a mat of Salvinia growth. Yes, that’s a WATERway! • causes low oxygen areas once it dies • prevents natural gas exchange, killing species trapped underneath • problems with flood mitigation, boating, and irrigation Salvinia Weevil Control: the weevil Cyrtobagous salviniae, one of salvinia’s natural predators from its native habitat, was introduced to keep the population in check. Common Periwinkle (Littorina littorea) Native to: Europe Transported by: ballast water, 1870s Common Periwinkle (Littorina littorea) Impacts: • competes with native Littorina species • reaches very high densities, making it hard for other species to find free spaces to occupy • allows the slow-growing algae Chondrus crispus to dominate the algal community by feeding on the faster-growing algal species When the periwinkle is present, the algae Chondrus crispus can completely take over an algal community. • allows survival of the parasite that causes marine black spot disease, which affects marine fish and birds, by being the first host for the parasite Green Crab (Carcinus maenas) Native to: the Baltic Sea Transported by: shipworm burrows in ship hulls, end of the 18th century Green Crab (Carcinus maenas) Impacts: • competes with native crabs for resources • voracious predator and scavenger on many marine species • consumes juvenile shellfish, and probably contributed to the decline of the softshell clam (Mya arenaria) industry in Long Island Sound Clam industry suffered due to the depletion of clam stocks by green crab predation. Dead Man’s Fingers (Codium fragile) Native to: Asia Transported by: attached to hulls of ships Dead Man’s Fingers (Codium fragile) Impacts: • grows around oyster or scallop and, as the plant grows, it becomes buoyant and drifts off with the shellfish attached; often called the “oyster thief” or “scallop thief” Dead man’s fingers growing on an oyster. If the plant becomes buoyant enough, the oyster will float away with it. Lionfish (Pterois volitans) Native to: Indian and Pacific Oceans Transported by: people bringing them over for aquariums, first observed here in 2001 Lionfish (Pterois volitans) Impacts: • preys on native species • has venomous spines MSX Oyster Disease (Haplosporidium nelsoni) Native to: Asia Transported by: people illegally planting Japanese oysters in the Delaware Bay in 1957, spread from there MSX Oyster Disease (Haplosporidium nelsoni) Impacts: • parasite that caused extensive mortality of Eastern oysters (Crassostrea virginica) Asian Shore Crab (Hemigrapsus sanguineus) Native to: Asia Transported by: probably ballast, first observed in Cape May in 1987 Asian Shore Crab (Hemigrapsus sanguineus) Blue mussel may be consumed by the Asian shore crab. Impacts: • may consume barnacles, clams, oysters, and mussels • competes with native species • may outcompete green crab, another invasive crab species Green crab populations may decline due to competition with the Asian shore crab. Asian Longhorned Beetle (Anoplophora glabripennis) Native to: Asia Transported by: came in wooden packing material in cargo shipments from China Asian Longhorned Beetle (Anoplophora glabripennis) Impacts: • causes death of many tree species, especially maples (Acer spp.), poplars (Populus spp.), birches (Betula spp.), elms (Ulmus spp.) Beetle exit holes (arrow E), and where eggs are laid (arrow O) on a maple tree. Control: • cut down infected trees and destroy the wood Tiger Mosquito (Aedes albopictus) Native to: Asia Transported by: eggs laid in tires Tiger Mosquito (Aedes albopictus) Impacts: • feeds during daytime and dusk • irritating bite • may transmit eastern equine encephalitis, a virus that can affect birds, horses, and humans Eastern Equine Encephalitis (EEE) Japanese Beetles (Popillia japonica) Native to: Japan Transported by: grubs in iris roots imported from a Japanese nursery, early 1900s Japanese Beetles (Popillia japonica) Impacts: • pest to about 200 plant species, including rose bushes, grapes, hops, and others • damage plants by consuming only the leaf material between the veins Japanese beetles on a rose plant.