You are falling asleep at night and you hear the scurry, scurry, scurry on the roof above you. You wonder what it is and you think to yourself for a minute I bet it's rats. Most people just get creeped out by the fact that rats are actually really important for the outside ecosystem where they come from. Hi I'm Janice Creneti and I have been teaching environmental science for about 20 years and I am here to answer the question where do rats live? Well the short answer is just about anywhere they want. Rats actually are found all over the world. They are found on pretty much every continent except Antarctica. They can survive in very cold temperatures and also very hot humid temperatures. There are Norway rats and roof rats and they come from all different places all over the globe. One of the reasons that we have so many rats here is because we import goods from a lot of different places. Rats can actually become what we call an invasive species. It means they come from somewhere else, they get out in our ecosystem and they start to cause problems, particularly in our houses. You see they will hide in a shipment of bananas or tomatoes or whatever is being shipped from somewhere else over on the cargo boats. That is how they actually first arrived in the United States on those cargo ships. Well once they are here they breed very quickly and they can get into tiny spaces even inch by an inch. They like to build nests where they can lay or they can have their babies and where they can also stay warm when the night cools off a little bit even though they are warm blooded they need that extra protection particularly if they are living in colder climates. Rats will live inside your house. They'll live in forests. They will build nests inside your house. They will also build nests out in the environment out of straw, out of leaves, whatever they can find. They are pretty ingenious little devils and they can survive just about anywhere. They are also fed on by a lot of things which is part of why they need to breed as often as they do. That's good news for the people that are eating or the animals that are eating rats but not so good for the people that are living in houses and trying to get rid of them, but plug up the holes, discourage your environment from being suitable for rats and you can probably chase them away eventually. I'm Janice Creneti and this is where do rats live.