Thinahtea Protected Area overlaps with traditional use areas of the Slavey, Cree and Beaver cultures of the Dene Tha and Fort Nelson First Nations. Thinahtea means where the giants laid down.
The protected area represents features of the Petitot Plain Ecosection in the Boreal white and black spruce biogeoclimatic zone. There are significant jackpine stands mixed amongst the muskeg.
The area contains important habitat for caribou, moose wolf, black bear and several other mammals and waterfowl; endangered, threatened and vulnerable species include trumpeter swans and water hemlock which has been collected at the Petitot River. The Petitot River and Thinahtea Lake contain several fish species such as Northern pike, walleye, burbot, longnose sucker, troutperch, longnose dace, and slimy sculpin.