What is biosecurity?
Biosecurity encompasses the policies and measures taken to protect people, natural resources, plants and animals against potentially harmful species and diseases from other countries. It is a relatively new term that gained currency in New Zealand from the 1990s – especially after the passing of the Biosecurity Act 1993.
In the past biosecurity mainly involved quarantine stations and border inspections. The focus was largely economic, aiming to protect the agricultural, horticultural and forestry industries from exotic pests and diseases.
Later, people became concerned about the negative impact of some introduced species on New Zealand’s environment, and native plants and animals. Introduced invasive species are the biggest threat to many native species – and growth in trade and tourism has increased the chances of new species arriving. These realisations have led to a more systematic and wide-ranging approach to protecting New Zealand, including more attention to marine biosecurity.
The early fear was disease – for humans, and for animals such as sheep and cattle. From the 1860s major ports built quarantine stations on islands. Incoming ships with sick people on board had to unload their passengers there until the all-clear was given. Port Chalmers was served by a station on Quarantine Island/Kamau Taurua, Lyttelton by Ōtamahua/Quail Island, Wellington by Matiu/Somes Island and Auckland by Motuihe Island. Many of these islands also had animal quarantine facilities, where imported animals stayed in yards until it was clear that they were free of disease.
Attitudes towards importing exotic species have changed. From the 1840s European settlers imported many plants and animals that they thought were useful. In the 1860s acclimatisation societies were set up specifically to introduce exotic species. Settlers had some limited awareness of the potential for harmful introductions – under the Protection of Animals Act 1867 no one could import ‘any fox, venomous reptile, hawk, vulture or other bird of prey’. People could bring in and liberate any other species (unless it was deemed a threat to agriculture) until 1896, when the act was amended to give the government full control over animal importations.
In the 1860s some settlers spoke out against introductions of exotic species. They were voices in the wilderness – most believed that animals from the old country (Britain) could not possibly be harmful. But farmers were soon struggling with the ‘small bird nuisance’ (introduced sparrows eating crops) and the ‘rabbit nuisance’ (rabbits eating pasture). Gorse spread from its intended hedgerows and became a prolific weed, and mustelids (stoats, ferrets and weasels), introduced to control rabbits, munched on native birds instead.
Legislation to protect farming
The 1849 Sheep Ordinance was introduced to protect sheep from imported diseases such as scab. Scab, caused by the mite Psoroptes ovis, made infected sheep lose condition and sometimes die. Imported sheep had to be inspected, and infected animals were quarantined.
The Diseased Cattle Act 1861 allowed provincial governments to ban the importation of cattle from diseased areas. Yet the government had little overall control of importation of farm animals until the Animals Importation Prohibition Act was passed in 1876. This allowed it to block imports of any animal that posed a threat to agriculture. The Codlin Moth Act was passed in 1884 after an outbreak of codling moth threatened fruit production. The Department of Agriculture began inspecting fruit and plants arriving at ports in the 1890s. Other legislation followed, with a focus on protecting productive industries from specific pests or diseases.
It was soon realised that many pests and diseases found in other parts of the world were absent from New Zealand, giving farmers a competitive advantage. But every new importation of animals or plants risked introducing new problems. Regulations governing importations became stricter over the 1900s, but were not comprehensive. For example, the Noxious Weeds Act of 1900 focused on threats that weeds posed to farming, not the natural environment. While the government was watching out for farm weeds, ornamental garden plants were easily imported. Many naturalised and became problem weeds in the bush.