Is it possible to tag an area that is protected and/or has endangered species?
Yes you can see boundary= protected_area:
You can use protect_class= to specify the type of protection:
And also see leisure=nature_reserve
Does this answer your question?
I do want to mention that there are some ethics involved in mapping endangered speices (and in this case I mostly mean mentioning or specifically tagging it with
species=*. If its a legal and well defined boundary, or a well known fact that this animal lives there, then this is probably no problem. But the act of mapping endangered species can cause harm, as it can attract people that are interested in endangered species for a variety of reasons. Like seriously, species have gone extict because people were too obsessed in spotting or catching species purely because they were endangered and rare.
The wiki page on mapping birds nests goes in to this in pretty good detail, though focussed on birds for obvious reasons. It gives a good overview of when to map and when not to map.