Elven Hunting Language - Sign Language

The elvish hunters over the centuries have developed a complicated and complete sign language to be used in hunting situations.
The origins of this language may predate Coalescence. This language is quite possibly borrowed, or has deviated to such an extent that the rules of grammar and syntax are quite different than the spoken language. Learning this language is very much like learning a whole new language along with also needing to learn the complex finger symbols.
The language takes advantage of the low light vision ability of all elves, in that it is meant to used close to the body, often having the finger positions in the shadows.
While complete, the language does have some particulars which make it great for hunting. It is heavy on timing and distance descriptors. The elves who practice this regularly will also use it in combat situations as it also works quite effective in tactical situations. However, as a utility language with a purpose, it is weak when used on abstract concepts like love and honor. This doesn't mean it can't be used as such - in fact over the centuries the practitioners will regularly try and hold complete discussions for practice.
There is no written version. Regular elvish script is used for written messages.
Due to the nature of the language, it is more varied by region than spoken elvish. A mere hundred miles will see the language transformed so that communication is difficult between two signers from different villages.
While hunting or in combat situations, communication is almost as fast as normal spoken communication. For more abstract ideas, the communication takes two to three times as long.
The range of the language is effective at 30' in night or dark situations, 60' during the day. Direct line of sight is required. It takes a DC of 15 and viewing the target to detect the use of the signing if the signer is trying to remain unnoticed (its not designed to be discrete and hidden like some thieves signs.) All ideas can be transmitted at half speed if only one hand is available to sign with - this is a limited usage design function of the language as it allows one hand free to perform other actions like holding onto a bow.
It is learned just like any other language by using a skill point. It is not secret, so that means there is no taboo in teaching others the language. In fact, most elves which know the language are flattered when other races take the time to learn their heritage.
Elves near Chrailis have abandoned this heritage centuries ago, so near the city, few elves know or understand the language. This is primarily a tool used by more remote jungle elf tribes.
This counts as one language choice if chosen and is not actually a sub-language of the written language