Learn English – What do you call the battery slot’s ends

There are "anklets", which are worn around the ankles.

From Wikipedia:

An anklet, also called ankle chain, ankle bracelet or ankle string, is an ornament worn around the ankle.

Note that "ankle bracelet" in some contexts could be misconstrued as an ankle monitoring device used in law enforcement.

Also, please note that "bracelets" are worn around the wrists. It is clear and natural to say someone wore a bracelet on their arm, but most native speakers will take that to mean it is on that person's wrist. I think the object in your picture would be worn on the upper arm, and therefore is not a bracelet.

There is something called a "bangle". Here is Wikipedia on bangles, for convenience:

"Bangle" on Wikipedia

But yes, in some cases you would simply say "jewelry". (I suggest not calling it a "jewel") Leg-jewelry is little bit odd, so, personally, I would rearrange the phrase to say (He wore) "jewelry on his leg".

I think the term you might be looking for is 'taxidermy mounts'.

Taxidermy is the preserving of an animal's body for the purpose of being put on display. A person who creates these displays is called a 'taxidermist'. The end result is called a 'taxidermy mount' or just simply 'taxidermy'. There are different methods used in taxidermy such as overlaying the animal's skin over a frame of wood and wire and then stuffing it with cotton, creating replicas with resin or fiber glass, or freeze drying the whole animal and removing its organs.

Preserving chemicals are sometimes applied to the skin used, or the skin is tanned, which is why they do not rot over time.