Advice Needed again: the RAT

Thanks everyone for their advice in response to the last post. Now I need new advice:

As I have mentioned before, I am staying in the basement right now. As such, I have the typical basement windows--where there is a hole dug out of the ground and then the window lets in a tiny bit of sunlight (but mostly you just stare at the window well). So, anyway, today I looked out the window and here's what there was:

a RAT!!

Just kidding, it wasn't that big. It was more like this:

The truth is, it didn't freak me out that much. I used to have a pet rat. The only difference is, this one could be carrying the bubonic plague. No big deal. I began to watch him (or possibly her, I don't want to gender stereotype here):

As I watched, I realized that he was running around in circles. He was trapped in the window well. Poor little thing. So now what?
I thought about my options. Here's what I came up with:
1. Rat poison, finish him off quickly
2. Let him starve to death in the well.
3. Help him get out.
So the problem with both number 1 and 2 is that I will then have a DEAD rat to fish out and that is disgusting. I'd rather have him escape on his own.
So I made a ladder. I took a board and put it at the smallest angle I could and figured he would just climb right out and go find his family and live happily ever after.

Problem is, he can't figure it out. He gets on the bottom of it and can't figure it out. Does he think that I am tricking him? Is it too steep?

So now what? Any ideas?
I need advice FAST before he starves to death.