Clematis vitalba smothering a Cordyline australis

A number of

introduced species An introduced species, alien species, exotic species, adventive species, immigrant species, foreign species, non-indigenous species, or non-native species is a species living outside its native distributional range, but which has arrived ther ...

, some of which have become

invasive species An invasive species is an introduced species that harms its new environment. Invasive species adversely affect habitats and bioregions, causing ecological, environmental, and/or economic damage. The term can also be used for native spec ...

, have been added to

New Zealand New Zealand () is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and List of islands of New Zealand, over 600 smaller islands. It is the List of isla ...

's native flora and fauna. Both deliberate and accidental introductions have been made from the time of the first human settlement, with several waves of Polynesian people at some time before the year 1300, followed by Europeans after 1769. Almost without exception, the introduced species have been detrimental to the native flora and fauna, but some, such as farmed sheep and cows and the

clover Clovers, also called trefoils, are plants of the genus ''Trifolium'' (), consisting of about 300 species of flowering plants in the legume family Fabaceae originating in Europe. The genus has a cosmopolitan distribution with the highest diversit ...

upon which they feed, now form a large part of the economy of New Zealand. Possibility of introduced

herbivore A herbivore is an animal anatomically and physiologically evolved to feed on plants, especially upon vascular tissues such as foliage, fruits or seeds, as the main component of its diet. These more broadly also encompass animals that eat ...

s ( deer) to serve as ecological proxies for extinct moa has been questioned. Biosecurity New Zealand maintains registers and lists of species that are invasive, potentially invasive, or a threat to agriculture or biodiversity. They also manage a small number of species under the National Interest Pest Responses (NIPR) programme. The rainbow lorikeet is the one animal that has been covered by the NIPR, and was eradicated in 2014. All the other species covered by the NIPR, past or present, are weeds.

Animal species

Many invasive animal species are listed in schedules 5 and 6 of the

Wildlife Act 1953 Wildlife Act 1953 is an Act of Parliament in New Zealand. Under the act, the majority of native New Zealand vertebrate species are protected by law, and may not be hunted, killed, eaten or possessed. Violations may be punished with fines of up t ...

. Those in Schedule 5 have no protection and may be killed. Those in Schedule 6 are declared to be noxious animals and subject to the

Wild Animal Control Act 1977 The Wild Animal Control Act 1977 is a current Act of Parliament in New Zealand New Zealand () is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()— ...

. In 2016 the New Zealand government introduced Predator Free 2050, a project to eliminate all non-native predators (such as rats, possums and stoats) by 2050. Some of the invasive animal species are as follows.

Mammals

Brown rat The brown rat (''Rattus norvegicus''), also known as the common rat, street rat, sewer rat, wharf rat, Hanover rat, Norway rat and Norwegian rat, is a widespread species of common rat. One of the largest Muroidea, muroids, it is a brown or grey ...

or Norway rat (''Rattus norvegicus'') * Black rat (''Rattus rattus'') * Kiore (Polynesian rat) * Cat * Chamois *

Common brushtail possum The common brushtail possum (''Trichosurus vulpecula'', from the Ancient Greek, Greek for "furry tailed" and the Latin for "little fox", previously in the genus ''Phalangista'') is a nocturnal, semiarboreal marsupial of the family Phalangeridae ...

(''Trichosurus vulpecula'') * Dog * European hare * European hedgehog * European rabbit (''Oryctolagus cuniculus'') *

Fallow deer Fallow deer is the common name for species of deer in the genus ''Dama'' of subfamily Cervinae. There are two living species, the European fallow deer (''Dama dama''), native to Europe and Anatolia, and the Persian fallow deer (''Dama mesopotamic ...

* Ferret (''Mustela putorius furo'') *

Goat The goat or domestic goat (''Capra hircus'') is a species of Caprinae, goat-antelope that is mostly kept as livestock. It was domesticated from the wild goat (''C. aegagrus'') of Southwest Asia and Eastern Europe. The goat is a member of the ...

* Himalayan tahr *

Horse The horse (''Equus ferus caballus'') is a domesticated, one-toed, hoofed mammal. It belongs to the taxonomic family Equidae and is one of two extant subspecies of ''Equus ferus''. The horse has evolved over the past 45 to 55 mi ...

(''Equus ferus caballus'') * House mouse (''Mus musculus'') * Least weasel * Pig * Stoat (''Mustela erminea'') *

Red deer The red deer (''Cervus elaphus'') is one of the largest deer species. A male red deer is called a stag or Hart (deer), hart, and a female is called a doe or hind. The red deer inhabits most of Europe, the Caucasus Mountains region, Anatolia, Ir ...

* Rusa deer * Sambar deer * Sika deer *

Wallaby A wallaby () is a small or middle-sized Macropodidae, macropod native to Australia and New Guinea, with introduced populations in New Zealand, Hawaii, the United Kingdom and other countries. They belong to the same Taxonomy (biology), taxon ...

* Wapiti (elk) * Whitetail deer

Reptiles

*Plague skink or rainbow skink ('' Lampropholis delicata'')

Birds

* Australian magpie * Canada goose * Cirl bunting * Common mynaLowe S., Browne M., Boudjelas S. and de Poorter M. (2000, updated 2004)
100 of the World's Worst Invasive Alien Species: A selection from the Global Invasive Species Database
. The Invasive Species Specialist Group (ISSG), a specialist group of the Species Survival Commission (SSC) of the World Conservation Union (IUCN), Auckland. * Common redpoll * Common starling * Dunnock * European goldfinch * European greenfinch * Mallard * Mute Swan * Rainbow lorikeet * Rook * Yellowhammer

Fish

* Koi * '' Gambusia affinis'' * Common rudd * Catfish * Brown trout

Invertebrates

*Argentine ant ('' Linepithema humile'') *Asian paddle crab ('' Charybdis japonica'') *Asian paper wasp ('' Polistes chinensis'') *Australian paper wasp ('' Polistes humilis'') *Carpet sea squirt ('' Didemnum vexillum'') *Common wasp ('' Vespula vulgaris'') *European paper wasp ('' Polistes dominula'') *German wasp ('' Vespula germanica'') *Varroa mite ('' Varroa destructor'')

Spiders

* there are 73 known introduced spiders, of which 50 are

Australia Australia, officially the Commonwealth of Australia, is a country comprising mainland Australia, the mainland of the Australia (continent), Australian continent, the island of Tasmania and list of islands of Australia, numerous smaller isl ...

n, including :*'' Philoponella congregabilis'' :*The redback, ''Latrodectus hasselti'', thought to have arrived with a steel shipment in the 1980s

Plant and other non-animal species

The National Pest Plant Accord, with a listing of about 120 genus, species, hybrids and subspecies, was developed to limit the spread of plant pests. Invasive plants are classified as such on a regional basis with some plants declared as national plant pests. Biosecurity New Zealand manages a small number of weeds under the National Interest Pest Responses programme. As of May 2024, NIPR covers nine weeds. Hornwort ('' Ceratophyllum demersum'') was covered until it was eradicated in 2014. Additionally, the Department of Conservation lists 328 vascular plant species as environmental weeds. Some of the better-known invasive plant species are: *'' Acacia'' species (mostly Australian) especially wattle *'' Acanthus'' - bear's breeches *'' Agapanthus'' *Arrowhead ('' Sagittaria sagittifolia'') *'' Arundo donax'' - giant reed (or elephant grass) *Asiatic knotweed ('' Reynoutria japonica'' or ''Fallopia japonica'') * Banana passionfruit * Blackberry * Boneseed ('' Chrysanthemoides monilifera'') * Boxthorn (''Lycium ferossimum'') * Broom (''Cytisus scoparius'') * Buckthorn (''Rhamnus alaternus'') * Californian thistle (''Cirsium arvense'') * Cape sundew (''Drosera capensis'') * Cape tulip * Castor oil plant (''Ricinus communis'') * Caulerpa brachypus * Caulerpa parvifolia * Christmasberry (''Schinus terebinthifolius'') * Climbing asparagus (''Asparagus scandens'') * Darwin's barberry (''Berberis darwnii'') *'' Didymosphenia geminata'' ("didymo" or "rock snot") *Field horsetail ('' Equisetum arvense'') *'' Glyceria maxima'', also called ''Poa aquatica'' * Gorse (''Ulex europaeus'') * Heather (''Calluna vulgaris'') * Japanese honeysuckle (''Lonicera japonica'') *

Jasmine Jasmine (botanical name: ''Jasminum'', pronounced ) is a genus of shrubs and vines in the olive family of Oleaceae. It contains around 200 species native to tropical and warm temperate regions of Eurasia, Africa, and Oceania. Jasmines are wid ...

(''Jasminum polyanthum'') * Kahili ginger (''Hedychium gardnerianum'') *''

Lantana camara ''Lantana camara'' (common lantana) is a species of flowering plant in the verbena family (Verbenaceae), native to the American tropics. It is a very adaptable species, which can inhabit a wide variety of ecosystems; once it has been introduced i ...

'' * Lodgepole pine (''Pinus contorta'') * Loquat (''Eriobotrya japonica'') *

Lupin ''Lupinus'', commonly known as lupin, lupine, or regionally bluebonnet, is a genus of plants in the legume family Fabaceae. The genus includes over 199 species, with centres of diversity in North and South America. Smaller centres occur in No ...

*Madeira vine ('' Anredera cordifolia'') * Mexican daisy (''Erigeron karvinskianus'') * Mexican devil (''Ageratina adenophora'') *Mile-a-minute ('' Dipogon lignosus'') * Mistflower (''Ageratina riparia'') *

Morning glory Morning glory (also written as morning-glory) is the common name for over 1,000 species of flowering plants in the family Convolvulaceae, whose taxonomy and systematics remain in flux. These species are distributed across numerous genus, gene ...

(''Convolvulus'') * Moth plant (''Araujia sericifera'') * Old man's beard (''Clematis vitalba'') * Oxygen weed (''Egeria'') * Oxygen weed (''Lagarosiphon major'') * Pampas grass (''Cortaderia selloana'') * Privet ** Tree privet (''Ligustrum lucidum'') ** Chinese privet (''Ligustrum sinense'') * Purple loosestrife (''Lythrum salicaria'') * Queen of the night (''Cestrum nocturnum'') * Ragwort *'' Rhododendron ponticum'' *Royal fern ('' Osmunda regalis'') *'' Salix cinerea'' (gray willow) * ''Salix'' × ''fragilis'' (crack willow) * Scotch thistle (''Onopordum acanthium'') *Smilax ('' Asparagus asparagoides'') * Sycamore (''Acer pseudoplatanus'') *'' Tradescantia fluminensis'' *Water pennywort ('' Hydrocotyle umbellata'') *Woolly nightshade ('' Solanum mauritianum'') * Yellow flag (''Iris pseudacorus'')

Auckland Auckland ( ; ) is a large metropolitan city in the North Island of New Zealand. It has an urban population of about It is located in the greater Auckland Region, the area governed by Auckland Council, which includes outlying rural areas and ...

has been declared to be the weediest city in the world.

References

External links

Biosecurity New Zealand
government agency
Official New Zealand Pest Register
– searchable database at the Ministry for Primary Industries
Pests and threats
Department of Conservation
Information on plant pests
at Weedbusters ;Publications * * {{Oceania in topic, Invasive species in

Invasive species An invasive species is an introduced species that harms its new environment. Invasive species adversely affect habitats and bioregions, causing ecological, environmental, and/or economic damage. The term can also be used for native spec ...