It looks as though it has been dyed. To make it look more uniform and darker in color. The bridge, in particular, looks totally dyed with a flat black India Ink type of dye.
So it's difficult to tell which wood it is. I'd guess ebony but I'm not that familiar with pau ferro.
Pau Ferro is typically much lighter in colour, closer to something like mahogany or acacia, but I have seen Pau Ferro fretboards dyed as black as that. I don't think Ebony has the kind of grain to it as in the photos so I'm guessing it's just Pau Ferro dyed black.