No, not an expensive one off tool, though these woodpeckers do have a bright red head. I was cruising my wood lot the other day and spotted this very precisely crafted mortise in a cedar tree. The sides are perfectly tapered and the top/bottom are remarkably flat.

I went over to investigate and found out why.

This was a smaller cedar, <12", which aren't normally hollow heart yet but this one clearly was. The black ants obviously took advantage, as did the woodpecker(s). I came across another, similarly precise mortise in another cedar a few hundred yards away. Pretty sure these were crafted by Pileated Woodpeckers as the Norther Flickers we have tend to make a round hole. Could also be from a Red-naped Sapsucker but the mortise seems a little large for one of those. In any case I was pretty amazed at nature's craftsmanship.