What year was key largo founded?
I think you're referring to the Key Largo Cotton Mouse. It is not known how many Key Largo Cotton Mice are left. They are found only on Key Largo Island and are threatened by habitat loss. They are not an endangered species, however, because they are not a species. They are only a subspecies of the Cotton Mouse.
The Key Largo Woodrat is an an endangered species. The Burmese Python is an invasive species, and is harming many native and endangered species in the Everglades. A Burmese Python can even eat an alligator - it will eat anything, no matter what size. This is why the Key Largo Woodrat is threatened by the Burmese Pythons.