Holidaymakers warned not to take ants on holiday with them
Summer is a risk period for the spread of invasive pest ants – and holiday travellers are being asked to check that they
are not unwittingly aiding new ant incursions.
Argentine ants are major household pests, can harm native ecosystems, and bite people. Originally from South America,
they have spread around the world through trade and are now quite widespread in the North Island. They have also arrived
recently in Nelson. Darwin ants, originally from Australia, are also a significant household nuisance and may also
threaten native environments. They are now in the Christchurch area, especially around the Port Hills, and have been
spotted in Nelson, Blenheim, and various places in the North Island from Whangarei to Gisborne.
Landcare Research scientist Richard Toft says these pest ants form new nests over summer, and the inadvertent dispersal
of these nests is their main mode of spreading.
“These ants are very slow to move of their own accord. For example, it is estimated it would take Argentine ants 300
years to move from Kaitaia to Cape Reinga under their own steam!
“However, the ants are adept at nesting on human goods such as boats, trailers, camping gear, timber, pot plants –
anything that may have been left sitting outside.
“If you are in an area known to have Argentine or Darwin ants, check vehicles, plants or equipment that has been left
outside. If you do find ants on something you are intending to take elsewhere, please destroy the colony first.
“I would particularly encourage people to check their boats to help prevent the ants establishing on offshore islands.
Argentine ants established on Tiritiri Matangi Island north of Auckland after arriving by boat.”
Mr Toft says when it comes to ant invasions, prevention is far better than the cure.
“Small populations of ants can be eradicated easily, but once ants become established in urban areas, the best we can
usually hope for is localised control.”