List of Invasive species by country:

Australia

• See main article Invasive species in Australia

Plants

• Prickly pear (Opuntia spp.)
• Patterson's Curse (Echium plantagineum)

Birds and Mammals

• Rabbit (Oryctolagus cunicularis)
• House Sparrow (Passer domesticus)
• Feral cat (Felis silvestris catus)

Amphibian

• Cane Toad (Bufo marinus)

Europe

Plants

• Tree of heaven (Ailanthus altissima)
• desert false indigo (Amorpha fruticosa)
• grape caulerpa (Caulerpa racemosa)
• caulerpa (Caulerpa taxifolia); usually referring to the Mediterranean clone (1)
• Canadian pondweed (Elodea canadensis)
• Japanese knotweed (Fallopia japonica)
• Honey locust (Gleditsia triacanthos)
• Himalayan balsam (Impatiens glandulifera)
• Black locust (Robinia pseudoacacia)

Insects

• Colorado Beetle (Leptinotarsa decemlineata)

Birds and Mammals

• Canada Goose (Branta canadensis)
• House Mouse (Mus musculus)
• American Mink (Mustela vison)
• Coypu (Myocastor coypus)
• Muskrat (Ondatra zibethicus)
• Ruddy Duck (Oxyura jamaicensis)
• Brown Rat (Rattus norvegicus)
• Black Rat (Rattus rattus)
• Gray Squirrel (Sciurus carolinensis)

Pathogens

• Dutch elm disease (Ophiostoma ulmi)

New Zealand

See main article: Invasive species in New Zealand

Plants

• Boneseed
• Broom
• Gorse
• Heather
• Kahili Ginger
• Old man's beard
• Pampas Grass
• Ragwort
• Wandering Jew

Mammals

• Possum
• Rabbit
• Rat
• House mouse
• Stoat
• Ferret
• Hedgehog

Fish

• Grass carp

North America

Plants

• Air-potato (Dioscorea bulbifera)
• Australian pine (Casuarina equisetifolia)
• Autumn olive (Elaeagnus umbellata)
• Brazilian pepper (Schinus terebinthifolius)
• Brazilian waterweed (Egeria densa)
• Caulerpa (Caulerpa taxifolia); usually referring to the Mediterranean clone
• Camphor tree (Cinnamomum Camphora)
• Chinaberry (Melia azedarach)
• Chinese privet (Ligustrum sinense)
• Chinese tallow (Sapium sebiferum)
• cogon grass (Imperata cylindrical)
• Common broom (Cytisus scoparius)
• Common reed (Phragmites australis; also native, but European subspecies invasive 1)
• Cotton thistle (Onopordum acanthium)
• Coral ardisia (Ardisia crenata)
• Diffuse knapweed (Centaurea diffusa)
• Dog-strangling vine
• Downy brome, Cheatgrass (Bromus tectorum)
• Eurasian water-milfoil (Myriophyllum spicatum)
• Garlic mustard (Alliaria petiolata)
• Giant hogweed (Heracleum mantegazzianum)
• Giant-reed (Arundo donax)
• Giant salvinia (Salvinia molesta)
• Hydrilla (Hydrilla verticillata)
• Japanese honeysuckle (Lonicera japonica)
• Japanese knotweed (Polygonum cuspidatum)
• Japanese climbing fern (Lygodium japonicum)
• Kudzu (Pueraria montana var. lobata)
• Leafy spurge (Euphorbia esula)
• Melaleuca (Melaleuca quinquenervia)
• Mile-a-minute weed (Polygonum perfoliatum)
• Mimosa (Mimosa pudica)
• Multiflora rose (Rosa multiflora)
• Musk thistle (Carduus nutans)
• Natal grass (Rhynchelytrum repens)
• Old World climbing fern (Lygodium microphyllum)
• Orange Hawkweed (Hieracium aurantiacum)
• Pampas Grass (Cortaderia selloana)
• Purple loosestrife (Lythrum salicaria)
• Russian knapweed (Acroptilon repens)
• Russian Olive (Elaeagnus angustifolia)
• Saltcedar (Tamarix spp.)
• Silk-tree (Albizia julibrissin)
• Skunk vine (Paederia foetida)
• Spotted knapweed (Centaurea beibersteinii)
• Torpedo grass (Panicum repens)
• Tree of heaven (Ailanthus altissima)
• tropical soda apple (Solanum viarum)
• Water chestnut (Trapa natans)
• Water hyacinth (Eichhornia crassipes)
• Wild parsnip (Pastinaca sativa)
• Wild taro (Colocasia esculenta)
• Yellow star thistle (Centaurea solstitialis)

Insects

• Africanized honeybee (Apis mellifera scutellata)
• Asian long-horned beetle (Anoplophora glabripennis)
• Asian Tiger Mosquito (Aedes albopictus)
• Cactus moth (Cactoblastis cactorum)
• Emerald ash borer (Agrilus planipennis)
• European gypsy moth (Lymantria dispar)
• Formosan subterranean termite (Coptotermes formosanus)
• Glassy-winged sharpshooter (Homalodisca coagulata)
• Hemlock Woolly adelgid (Adelges tsugae)
• Japanese beetle (Popillia japonica)
• Red imported fire ant (Solenopsis invicta)
• Varroa mite (Varroa destructor)

Fish

• Alewife (Alosa pseudoharengus)
• Asian swamp eel (Monopterus albus)
• Eurasian ruffe (Gymnocephalus cernuus)
• Flathead catfish (Pylodictus olivaris)
• Sea Lamprey (Petromyzon marinus) in the Great Lakes
• Northern Snakehead (Channa argus)
• Round goby (Neogobius melanostomus)

Reptiles and Amphibians

• Brown tree snake (Boiga irregularis)
• Bullfrog (Rana catesbeiana)
• Cane toad (Bufo marinus)

Aquatic Invertebrates

• European green crab (Carcinus maenas)
• Veined rapa whelk (Rapana venosa)
• Zebra mussel (Dreissena polymorpha)

Birds and Mammals

• Coypu or Nutria (Myocastor coypus)
• European Starling (Sturnus vulgaris)
• House Sparrow (Passer domesticus)
• Wild Boar (Sus scrofa)

Pathogens

• Chestnut blight (Cryphonectria parasitica)
• Dutch elm disease (Ophiostoma ulmi)
• Exotic Newcastle Disease (Paramyxovirus)
• Fowlpox (Avipoxvirus )
• Plum Pox (Potyviruses : Potyviridae)
• Soybean Rust (Phakopsora pachyrhizi, Phakopsora meibomiae)
• Sudden Oak Death (Phytophthora ramorum)
• West Nile virus (Flavivirus)
• Whirling Disease (Myxobolus cerebralis)

Others

• earthworms, several species (lumbricid)