[4] Jarrah Forest is recognised globally as a significant hotspot of plant biodiversity and endemism, and is also managed for land uses such as water, timber and mineral production, recreation, and conservation.
[13]Carnaby's black cockatoo (Zenda latirostris) is endemic to south-west Western Australia and is listed as endangered under the EPBC of 1999.
[15] Other birds to inhabit Jarrah Forest include rare birds such as the forest red-tailed black cockatoo (Calyptorhynchus banksii naso), Muir's corella (Cacatua pastinator pastinator), black-throated whipbird (Psophodes nigrogularis), western bristlebird (Dasyornis longirostris), noisy scrub-bird (Atrichornis clamosus) and Baudin's black cockatoo (Calyptorhynchus baudinii).
[8] The first evidence of human habitation of the region was 50,000 years ago at Devil's Lair by ancestors of today's Aboriginal people.
Frequent burning reduced woody cover and encouraged the growth of low shrubs, herbs, and grasses, fostering open woodlands, shrublands, and savannas and limiting areas of dense forest and thicket.
The British started logging the jarrah forest in the 1840s to produce timber for use in construction, transport and power, and to protect water supplies.
[5] Jarrah was harvested for woodchips as well as high quality furniture and flooring until the WA government responded to decades of campaigning by placing a ban on native forest logging in 2024.
[23] Most of Jarrah Forest has been cleared for agriculture, timber and mining, leading to the consequent degradation of flora and fauna species and ecosystems.
[25] The significant population loss of fauna species in Jarrah Forest is attributed to the fox and cat (felis catus).
[24] Another introduced species that is a major threat to birds in some areas of Jarrah Forest, but for a very different reason, is the feral bee (Apis mellifera).
[26] Landscape fragmentation and the loss of suitable macro- and microhabitats can be detrimental to an animal's ability to live in or traverse through an area.
[27] With matrix permeability greatly reduced this wide-ranging carnivore is highly susceptible to being hit by vehicles as it crosses road reserves moving from one area to another.
[27] Despite the restoration and protection of jarrah forest in areas previously used by mine sites, the lack of hollow logs and stumps on the ground is evident.
[13] Suitable habitats can take decades to form and animals that rely on these for shelter, such as the chuditch and Egernia napoleonis, are left without.
[34] In December 2023, Premier Roger Cook began stricter control over Alcoa's mining operations ahead of the EPA's decision.
[35] Prevalent in the northern areas of Jarrah Forest, dieback disease, caused by the introduced soil-borne pathogen Phytophthora cinnamomi, is a serious threat to many plant species.
[5][36] The disease involves the formation of lesions (decaying tissue) starting in the roots and moving up the stem of a plant, and, in the case of many species, killing them.
[26] FORESTCHECK is a Department of Parks and Wildlife initiative that is responsible for monitoring biodiversity in the jarrah forests of south-west Western Australia.
[26] Focussing on timber harvesting and silviculture treatments in the present, future monitoring programs may be extended to include fire, climate change, mining, utility corridors and recreational use.
[5][36] Vertebrate fauna play a key role in jarrah forest ecosystem processes including pollination, grazing and predation.
[13] The chuditch, quenda and common brushtail possums are three such species considered essential in the development of a sustainable restored forest ecosystem.
[13] To prevent population numbers of these species and other vertebrates from further declining an aerial fox baiting program was introduced forest-wide.
Much of this region is under long-term mining leases for bauxite owned by Alcoa and Worsley who have actively resisted attempts to allow the WA government to create substantial and secure reserves.
[28] The implementation of the fox baiting program was expected to greatly increase the population numbers and range of native including the western ringtail possum which was re-introduced into the jarrah forest in the same time-frame.
[28] The abundance and distribution of the chuditch population in south-west WA has recovered quite significantly in the last decade and this has been attributed to the control of foxes.
[13] Capture rates (interpreted as mammal abundance) of the woylie, chuditch and common brushtail possum coincided with the efforts of this program.
[24] In 1974-1999 six mammals were listed as threatened under Australian Commonwealth and WA stage legislation, the woylie, tammar wallaby, quenda, chuditch, numbat and the western ringtail possum.
[13] The protection of old growth jarrah forest needs to continue, especially in the northern region and the best way to achieve this is to claw back some of the mining lease areas granted to Alcoa and Worsley and create substantial reserves with proper A Class status.
Additionally jarrah forest needs to be rehabilitated to promote further growth, decrease fragmentation and to maintain and improve flora and fauna biodiversity, a process that may take decades.