Lovely!
re: Orcs
I think the bases of those two arms of the mountain ranges that nearly cut off Gorgoroth from Nurn could sustain huntable animals - some small wily mountain goats, wild pigs in the scrubby growths of the foorhills, near the water sources. And yes - they would love to raid the gardens and fields. There might even be the occasional small hunting cat.
I do think that perhaps there would be tasty lizards and rodents of some sort available. The Orcs could keep guinea pig like animals, too, as a source of meat.