Pest Control - Rats
There are three rat species found in New Zealand. The two main species are the Norway or Brown Rat and the Common or Black Rat. They were both introduced by European settlers and are both pests associated with human activity. They are found in houses, dumps, waterways and cropland.
The third one is the Pacific Rat or Kiore which were introduced to New Zealand by Maori settlers. They are quite rare now and are only found in Fiordland and a few Islands including Stewart Island.
The Signs of Rat Infestations:
- Gnaw marks: new gnawings or holes tend to be rough whereas, old gnawings are smooth from wear.
- Droppings: Fresh droppings are soft and moist but old droppings are dried and hard. If there are different sized droppings in one area then there are probably both adult and young rats present which means there is an infestation.
- Tracks or footprints: Fresh tracks are clear and sharp while old tracks are at least partially covered by dust
- Rub marks: They are more noticeable and bigger in size than those of mice.
- Burrows: Indoors they often nest in materials like insulation. If the nest is active it will be free of dust and cobwebs
- Runways: Most rodents, including rats and mice like to use the same routes, usually along walls, stacked merchandise and the like. Active runways or paths are free of dust and cobwebs, with fresh droppings. Tracks may or may not be visible.
- Damaged items: Look out for damaged food packaging, especially around fresh droppings
Biology of Rats:
The Norway Brown Rat is the largest of the two European rats. It's tail is thick and shorter than it's body and the ears are relatively small and do not reach the eye when pressed forward. It also has a blunt nose
The Common Black Rat hovever, which is more common, has a tail larger than its body, and larger ears that cover the eyes when pressed forward. It has a pointed nose.
Control of Rats:
The key to any rat control program is pest species identification, sanitation, harborage elimination, and mouse-proofing the building.
Control is based on the behavioural habits of rats.
"The two main species are the Norway or Brown Rat and the Common or Black Rat. They were both introduced by European settlers and are both pests associated with human activity."
Did You Know?
A rat's teeth are very hard, can bite up to 6 times every second and their incisor teeth can grow more than 100mm per year.
Did You Know?
Second only to Humans, House Mice and the Brown Rat are the most successful mammals on the planet!