Article 13 pest species

 Kia ora my name is Jack Karetai-Barrett, and I’m a Year 10 student at Whakatane High School. This month, I am writing about pest animal species in New Zealand.

Aotearoa's unique ecosystems have faced significant challenges due to the introduction of various pest species, often with disastrous consequences. The arrival of the Pacific rat, or kiore, with the first Polynesian settlers around 1250–1300 CE marked the beginning of these challenges. Later, ship rats and Norway rats were introduced by European settlers, leading to widespread ecological damage. These rats have been instrumental in the decline of native species by preying on birds, bats, and insects crucial to a healthy ecosystem.

European rabbits were introduced to Aotearoa in the 1830s, making them among the earliest of our introduced pest animal species. Then, in the 1870s, stoats were introduced from Britain in an attempt to control the rapidly increasing rabbit population. Unfortunately, they quickly spread into native bush areas, where they preyed on eggs and young birds, devastating native bird populations. Wild cats, initially brought on ships to control rats, have also become a major threat, preying on native birds, lizards, and insects. This all reminds me of the song about the lady who swallowed the fly.

Possums (Trichosurus vulpecula), another destructive pest, were first brought from Australia in 1837 to Riverton in Southland with the intention of establishing a fur industry. The initial attempt failed, but following four subsequent attempts, by 1858 there was a population explosion. The successful introduction of possums is related to the establishment of fruit trees as a food source. Today, possums inhabit about 95% of all farmland, scrubland, and bush in Aotearoa. Their population density here is much higher than in most parts of Australia, leading to severe ecological consequences as they feed on leaves, fruits, and flowers, contributing to the decline of many tree species and threatening the habitats of native birds and insects. There is also some video evidence of possums consuming native bird eggs from nests.

Deer, goats, wallabys, and pigs, introduced for hunting and farming, have also caused extensive damage to Aotearoa’s forests. Deer, brought in from 1851 to provide game for hunters, have significantly degraded forests due to their huge appetite for young foliage. Goats, initially used by early farmers to control invasive plants like blackberry and gorse (also intentionally introduced), have since gone wild, further damaging native bush. Wild pigs, introduced by Captain James Cook, disturb the ground as they forage, causing additional harm to the native ecosystem.

The introduction of these species was often supported by acclimatisation societies, established by European colonists in the 1860s. These societies aimed to naturalise new species in Aotearoa, not understanding they would have harmful effects. These societies were even legally recognised and supported by Animal Protection Acts, and they continued their activities well into the late 19th century. The Tauranga Acclimatisation Society, for instance, received funding to introduce pheasants and fallow deer, which now thrive around Aotearoa at the expense of our native species. It is interesting to read the old minute books of the Society, available online on the Tauranga City Libraries page. 

There are lots of methods of managing pest species. They include the use of toxins, and traditional methods such as trapping and shooting. I am a hunter, and one of my jobs in our family is to keep Mum’s freezer full of deer and goats.  Hunters, particularly on farms, play a crucial role in managing pest populations. They actively shoot pests like deer, pigs, and goats, helping to minimise the damage these animals cause to the land. Trappers, on the other hand, work tirelessly to control populations of smaller pests like possums and stoats. The combined efforts of these methods are essential in protecting Aotearoa's natural environment.

The history of introduced species in Aotearoa is a reminder of the far-reaching impacts that human actions can have on ecosystems. The ongoing efforts to control these pests are crucial in preserving our country’s unique natural environment for future generations.

Ka ora te whenua, ka ora te tāngata; When the land is well, the people are well. 

We are all responsible for our natural world; we all have to work together to protect our native species, and minimise the impact of pest species on our beautiful land.