Very nice picture. I was actually there on saturday as well, but the male lion wasn't doing much of anything when I was there. Here's one I got of the female lion. I'm still learning how to use my D80 as well. Hope you don't mind my addition to your thread.
This was taken with a D80 + 18-200mm VR DX. Not the sharpest lense out there, but it's the only lense I have aside from my kit lense (18-55mm).
The rest of the pictures I got on in this gallery:
http://michaelluu.smugmug.com/gallery/3451095#193794739