$500 Bonus at Work - Only $356 Net??

My work announced everyone was getting a $500 bonus and I do see it listed on my check, however after taxes I am only seeing an increase of $356 from my normal check. I can't seem to figure out why it was taxed so hard? The federal withholding alone was $106 extra and the rest was split up between state and Medicare.

Does this seem right? I expected a little over $400.