Red=Grey?

[Lt.LowSelfEsteem]

So I've been working on this picture, but I've run into a roadblock.

   

I want to make this black bat red. So I use the fuzzy select tool ad highlight the bat. 

   

I select my desired shade of red and click on the bucket tool, all is going according to plan.

   

So I click on the bat with my bucket selected and...

   

What? This isn't just exclusive to red, with green it turns to a lighter grey and with yellow it turns white. What am I missing so that I can make the bat the color I've actually selected?