The Conservation Commission of Western Australia, responsible for assessing and auditing the performance of the department, was also created by the CALM Act.

[3] Now (as of 2020[update] renamed the Conservation and Parks Commission),[4] its functions have broadened, with its purpose stated as "to act as an independent and trusted community steward and government advisor for the protection of Western Australia’s biodiversity and conservation estate while fostering its appreciation and sustainable use".

CALM was responsible for the wildlife conservation project Western Shield which is pest animal control (more than 3.9 million hectares of conservation reserves and State forests baited for feral animal control).

CALM also managed two long distance trails: An important duty of the Department was wildfire prevention and suppression on its lands as well as fire prevention in unallocated Crown land and unmanaged reserves (89.1 million ha transferred from Department of Land Administration on 1 July 2003) by: Some of the most severe wildfires that the Department had to help to suppress, in chronological order, include: Earlier forms of nature conservation in Western Australia were under:[7] The Department maintained and coordinated a range of specialist equipment and emergency response vehicles.

This included pumpers and tankers and other equipment relating to operations involving search and rescue and firefighting.