Azores

    After escaping from hedges in the 19th century, sweet pittosporum (Pittosporum undulatum) now occupies 24,000 ha in the Azores, equivalent to 49 per cent of its forested area.

    Photo Credit: Anthony Calvert

    England

    An Australian barnacle (Austrominius modestus) that arrived on ships decades ago thrives today in England, including in the Thames, and also on the continent. It displaces native European barnacles.

    Photo Credit: Anthony Calvert

    France

    West of Paris, in the Forest of Rambouillet, drivers are warned by road signs to watch out for red-necked wallabies, the descendants of escapees from a wildlife park.

    Photo Credit: Anthony Calvert

    Germany

    Black swans that escaped from captivity or were released have formed small breeding populations in Germany, Italy, Belgium and elsewhere in Europe, and Japan
    as well.

    Photo Credit: Anthony Calvert

    Zambia  

    Africa lacks native crayfish, raising questions about the impacts Australian redclaw crayfish (Cherax quadricarinatus) are having in Lake Kariba in Zambia, and in other African wetlands.

    Photo Credit: Anthony Calvert

    South Africa

    Eucalypts are less invasive than many Australian plants, but in South Africa the river red gum (Eucalyptus camaldulensis) has spread along many watercourses.

    Photo Credit: Anthony Calvert

    Israel

    Israel is one of many countries to have golden wreath wattle (Acacia saligna) as a weed, with infestations in many places including the Judean Mountains and near Jerusalem.

    Photo Credit: Anthony Calvert

    India

    The Australian sugarcane planthopper (Perkinsiella saccharicida) has become
    a pest in most countries that grow sugar cane, including India.

    Photo Credit: Anthony Calvert

    Japan

    The redback spider (Latrodectus hasseltii) is a serious concern in Japan, where it has spread across much of the country, to the concern of residents.

    Photo Credit: Anthony Calvert

    Guam

    The eastern dwarf tree frog or eastern sedge-frog (Litoria fallax), is tiny, but that didn’t stop it somehow reaching Guam and thriving there.

    Photo Credit: Anthony Calvert

    Vanuatu

    Animals often undergo ‘ecological release’ when they establish somewhere new, and for the green and golden bell frog (Litoria aurea) that has included thriving in Vanuatu, which is hotter than its native New South Wales.

    Photo Credit: Anthony Calvert

    New Zealand

    The Australian paper wasp (Polistes humilis) is one of the stinging creatures New Zealand has acquired from Australia, along with the redback and huntsman spiders.

    Photo Credit: Anthony Calvert

    Hawaii

    When it was discovered in Hawaii a century ago, the common grass skink (Lampropholis delicata) was thought to be a native reptile.

    Photo Credit: Anthony Calvert

    Tahiti

    In Tahiti, silvereyes released in the 1930s to colour the landscape now spread the seeds of the island’s worst weed, miconia, a South American tree that covers vast areas of damaged rainforest.

    Photo Credit: Anthony Calvert

    California

    Vedalia beetle (Rodolia cardinalis) is a welcome Australian, taken to California in 1888 to feed on cottony cushion scale, an Australian sap-sucking bug.

    Photo Credit: Anthony Calvert

    Chile

    Silver wattle (Acacia dealbata) is very weedy in Chile, but also a useful source of firewood.

    Photo Credit: Anthony Calvert

    Florida

    A common paperbark tree (Melaleuca quinquefolia) can shed millions of seeds when it is killed, helping explain why it is southern Florida’s worst weed.

    Photo Credit: Anthony Calvert

    Jamaica

    After escaping from a botanic garden, sweet pittosporum (Pittosporum undulatum) spread over 1300ha of montane tropical rainforest in Jamaica, benefiting from hummingbirds that pollinate its flowers and Jamaican orioles that spread its seeds.

    Photo Credit: Anthony Calvert

    Argentina

    Trade in pot plants probably explains how the blue garden flatworm (Caenoplana coerulea) reached Argentina, one of many countries it has colonised.

    Photo Credit: Anthony Calvert

    Brazil

    In the Atlantic forests of Brazil the piccabeen palm (Archontophoenix cunninghamiana) is fast becoming a weed, owing to a high seed output.

    Photo Credit: Anthony Calvert

    Greenland

    The Australian spider beetle (Ptinus tectus) can survive winters in Greenland because it lives inside kitchens in stored foods.

    Photo Credit: Anthony Calvert

Aussie invasion: the impact of our natives overseas

By AG STAFF | September 4, 2017

Cane toads, rabbits, lantana…the destruction caused by introduced species to Australian shores is well known. But what about the impact of our natives overseas? Biologist Tim Low journeyed around the world to see just how damaging our flora and fauna have been to other ecosystems.