You need to resize it to no larger than 716px wide.
I will say however that I like it cropped this way as it eliminates a somewhat distracting background. The color cast is an interesting effect, I assume it's from the night time lighting as you shot this at a 1 sec. exposure time. You might also try experimenting with a B&W version.

I also prefer the cropped version, it brings the focus to the profile nicely. I like this picture, the only thing I would say is it's not very sharp - I would try a higher ISO and reduce the exposure time if you don't have a tripod because it's a shame to lose the crispness! Also, I agree with the person above about the colour cast and think it actually works here as the lion has that bronze tone already.