It may depend on your exact type of mooring
. I know in Europe
mooring can refer to tying to a pier at a marina or dropping an anchor
. If your intention is just to use an anchor
then most areas of Spain
allow this with restrictions in sea parks, crowded harbors, etc.
If mooring you mean to set a permanent block or other kind of permanent attachment to the bottom which you would leave in place and tie up between sailing or cruising then I believe this would be restricted.