Introduced Species.

The Black or Roof Rat…
In this essay, I will share information about an introduced species to New Zealand, the Black or Roof Rat. It will describe and explain facts about the rat, effects the rat had on native species which were already living here and the result of the rat on the population of the native species. It will also include ways and methods in which the introduced species is controlled and how effective those methods are.

The Black or Roof Rat often live in places like trees and vine covered fences. They can also be found near river banks and streams.
Rats are omnivores and will eat just about anything if they have to. They mostly feed on native seedlings, chick eggs, fruit and nuts.
Black or Roof Rats have a very poor sense of sight and rely on other senses such as smell, taste, touch and hearing to survive.

Many different types of rats were first introduced in to New Zealand by many different settlers but “black or roof rats” were introduced by the Europeans in the 1860s. The rats came over to New Zealand on the ships of Captain Cook with the early sealers and whalers.
Rats are a threat to breeding birds as they prey on eggs and chicks. These rats also eat foods such as seeds and berries which native birds feed on.
In result, many native bird species have been unable to adapt to rats and have no defence against them. This has over the years caused native birds to breed very slowly and New Zealand’s native bird population has dropped.


To control rats, The Department Of Conservation carries out rat control in areas where there are endangered native birds such as the kakapo and blue duck. Controlling the rats is done by several effective methods, trapping, poisoning and putting rats and other pets on mainland islands which are set up for predator management. The intention of this control is to keep rat numbers low enough to allow birds to breed and eggs to hatch.
It has been found that on areas where rat control has taken place there have been seedling recovery which shows that rats affect vegetation as well. This also shows that the methods The Department of Conservation is using are effective.
It is very important that the rat population is kept under control because New Zealand’s native birds would be at risk of extinction if they weren’t.