If the rat trusts you, often the rat will let you pick it up when you calmly and gently hold out your hand to it. The rat in the video is a Roof Rat, but this will also work for Norway rats.
Rats can be quick and hard to hold onto if they don’t want you to. So, your first goal should be to get your new rat to trust you. That way, it is less likely that it will jump down and, if it does, it will allow you to pick it up again.
If your rat doesn’t trust you yet, it may evade your attempts at picking it up, and possibly hide someplace. As you can imagine, rats are very good at hiding, and the more places where it can hide, the harder it will be to recapture. So, word to the wise, while your rat is first getting to know you, try to play with it someplace with limited places to hide. For example, we made a simple play area for socializing out baby rats from leftover cardboard boxes. Again, the rats in the video are Roof Rats, but the same principle applies for Norway rats.
If the rat has already escaped someplace in your house, you will want to quickly try to narrow down where the rat is to the best of your ability. Then, close doors and block as many escape routes as possible to keep the rat confined to the smallest possible area.
Next, give the rat a chance to calm down and it might either let you pick it up or return to it’s cage on its own. You’d be surprised how often this works if you are patient and friendly to the rat.
However, if the rat is too frightened or traumatized, that might not be an option, so in the meantime go order a no kill trap from Amazon or pick one up from Lowes or Home Depot. If your rat is a baby, you need a mouse sized one.
You will need a bigger one for adult rats
You just need to bait the trap with something tasty (cooked rice seems to work), put it where you think the rat probably is and leave it be overnight. If you have a camera that can see in the dark (like a Nest), you can watch the area around the trap to see if the rat is coming out, and if it gets trapped.
Now, you will need to carefully socialize it and gain its trust so this doesn’t happen again. Until it finally trusts you, your little Houdini will be a flight risk, so handle him/her accordingly!