Are orcs immortal??

[Mariska Greenleaf]

(feel free to argue with me. I want you to)

The Uruk-Hai, for example, are not immoortal, because it states that they were bred from orcs and men

Whether or not orcs, or some kind of orcs, are immortal, Uruk-hai are, as far as I know, not the result of breeding orcs and men.
Perhaps this misunderstanding arose with the making of the movie, in which Saruman is the one to create the Uruk-hai, while in the book Sauron creates them. Saruman did however cross orcs and men, known as Goblin-men. Maybe this lead to some confusion.

Back on topic.
I believe that orcs are immortal. Of course,
almost all of the known individual orcs are slain in battle, or killed in other circumstances. What is kinda remarkable is that Gorbag was slain in 3019 (III), at the age of more then 500 years, which would suggest his immortality. He was an Uruk-hai, so he was a later breed of orc.
And if these were immortal, and assuming that the first orcs are corrupted elves, I do believe that orcs are immortal.

Does anybody know what happened to Shagrat?