Rats
Rats are native to Europe and Asia but now they have spread all over the world because where people go, rats go too.
When people began exploring the world rats usually jumped on board the ships and were carried to faraway places by accident.
Apples or rats?
Soon after European settlers had arrived, New Zealand was full of rats. One settler who lived in Canterbury described how on one night he went out to find his birch tree was full of apples. “I rubbed my eyes and looked again’ he said, “Finally I picked up a long pole and poked one of the apples. The apple squeaked and all the fruit ran away!” What he thought was a tree full of fruit was a tree full of rats. Ew!
In New Zealand we have 3 different types of rat:
Kiore (Pacific Rat)
The kiore arrived around 700 years ago with Maori ancestors from Polynesia in their canoes. Maori used to hunt kiore for food and would often eat them whole because their bellies were full of tasty native berries. Maori also used kiore skins to make cloaks. Kiore used to live throughout New Zealand, however now they just live in Fiordland and offshore islands. This is because they can’t live in places that have Ship or Norway rats, which are bigger and more vicious than kiore.
Norway Rats
Norway rats came on the ships of European explorers like Captain Cook, in the late 1700’s. They are the biggest rats in New Zealand. They are also known as water rats because they like to live in wet places like swamps or damp forests. They aren’t very good climbers so they often eat animals that live on the ground, like our flightless birds and insects like the giant weta.
Ship Rats
Ship rats hitched a ride on the sailing ships that brought European settlers to New Zealand in the 1800’s. Ship rats usually live and make their nests in trees. Now ship rats live in forests and cities all over New Zealand.
Why are rats a problem?
Babies, babies everywhere
One thing rats are very good at is making more rats! A male and a female rat have babies, those babies have babies and on and on it goes. In one year that first pair of rats can have up to 15,000 descendants!
People have accidentally taken rats to islands and it has always been a disaster.
When rats came to New Zealand there was lots of food for them to eat, like insects, lizards, plants and birds eggs. There were also not very many animals that like to eat the rats. In other countries there are snakes, mongooses and other animals that eat rats but in New Zealand there were only a few owls and hawks that were keen to catch them. With all that food and nothing to stop them they spread around New Zealand very fast.
Rats could easily eat the eggs and chicks of our birds who didn’t know how to defend themselves and often couldn’t move very fast. Rats also developed a taste for insects like weta and the giant snails. Lizards and native frogs are also commonly eaten by rats as well.
Not only do they eat our animals and insects but they also eat a lot of the fruits and seeds in our native forests. Without seeds no new plants can grow and the forest slowly dies.
Rats also attract other introduced pests like stoats and cats, which both like to snack on rats. So whereever there are rats, stoats and cats are not far behind. That means even more threats to the creatures that live in the forest!
Fortunately there are lots of things that we can do to get rid of pests and help save our native species.
How can you help?
Even your own garden could be home to native birds, insects or lizards so help look after them by putting out rat traps or bait. It will help stop rats from getting into your house too!
