Mythopoeia

Flora - All natural wildlife indigenous to Australia.

Fauna - All natural animal life, indigenous to Australia. (Koalas were genetically engineered to be able to procreate at an alarming rate due to the readily available food source they can provide for prisoners. This genetically engineered mutation resulted in Koalas becoming the incessant vermin of the island. But also still a food source.

Conlang - Most languages are the same. English is primary. Mandarin is a close second. There are various hybrids of slang used, Hindi slang mixed with Cantonese. American slang mixed with British slang and so on and so forth.