Just simple pieces of wood rotting away that I found. I let them dry for a few days and cleaned them up. Originally I planned to give them a clear coat, but someone suggested to stain them, which was a much better idea, so that's what I did.
I also made a third one, but that one is so big that filming it makes no sense because you wouldn't be able to see the details.
Here are the original 'build' threads, maybe you are interested in looking at some pics.
GonzmingoBig oneFishy