They are on the ancient Croc in upper guk. His replacement spawn is
from one to 5 gators. The necessary lvl escapes me but I'd say its 34
solo (although a pure caster can probably do them at 30) to be safe.
The gators won't agro so you can kill one at a time. You have to clear
them all out before the next spawn cycle will start.

They weight only .4 so they do drop your overall weight significantly.

Mal