The pressures affecting biodiversity remain largely consistent with those identified in the 1996, 2001, 2006 and 2011 state of the environment reports.

The most significant current pressures are clearing, fragmentation and declining quality of habitat; invasive species; climate change; changed fire regimes; grazing; and changed hydrology. Most of these exert a high to very high pressure on biodiversity, and are worsening. The cumulative and interacting effects of many of these pressures amplify the threat to biodiversity in Australia. Jurisdictional reports all note that their understanding of the full impact of these key pressures on biodiversity is low because of the inadequacy of long-term data and monitoring.

Clearing has stabilised across most states since 2011, except in Queensland. However, the legacy of past clearing means that its effects on biodiversity are not decreasing. High rates of population growth in urban and peri-urban areas result in continued conversion and degradation of the surrounding natural ecosystems.

The pressure from invasive species and pathogens continues a very high and worsening trend. Invasive plants and animals are the most frequently cited threats to species listed in the Environment Protection and Biodiversity Conservation Act 1999, and account for 12 of the 21 identified key threatening processes. Almost all states and territories note that data on the distribution and abundance of pest plants and animals, and management effectiveness for these pests are poor.

The impacts of a changing climate are increasingly clear, and include changes to ecosystem structure and composition, phenology (timing of lifecycle events), fire regimes and hydrology. Climate variability and climate change are also considered to have a high or very high impact, with a worsening trend in coastal, marine and inland water environments, and a range of impacts on aquatic biodiversity.

Livestock production is considered a major contributing factor to the decline of threatened mammals in northern Australia and, in conjunction with other pressures, contributes to changes in bird populations. However, the complete impact of grazing on biodiversity and ecosystem functioning is largely unknown.