Jurisdictional reporting on pressures

2016

Each state and territory in Australia has highlighted a range of key pressures in their jurisdictional reporting. Many of these pressures are common across all jurisdictions—for example, land clearing and vegetation fragmentation, pest animals, weeds, disease and pressures resulting from climate change—with varying impacts in each jurisdiction. Understanding of the full impact of these key pressures on biodiversity is generally considered to be low because of the inadequacy of long-term data and monitoring.

Australian Capital Territory

  • Key pressures:
    • Major threats are habitat loss and modification, pest plants and animals, and altered fire regimes.
    • Connectivity is being lost through developments such as the Majura Parkway and urban development, but key links are being protected, and revegetation is undertaken in other key areas for connectivity.
  • Assessment grade and adequacy of information:
    • Distribution and abundance of non-native species: status—high; trend—stable; confidence—low. Little specific assessment has been done on the effects of pests and weeds on biodiversity, or the abundance and distribution of weed species.
    • Fire: status—low; trend—stable; confidence—limited. The uncertainty comes from the limited data on effects of fire on biodiversity in the Australian Capital Territory.

New South Wales

  • Key pressures:
    • The pressure affecting the largest number of terrestrial threatened species in New South Wales (87 per cent) is clearing and disturbance of native vegetation, followed by invasive pest and weed species.
    • Currently, 46 key threatening processes are listed in state legislation; 1 key threatening process has been listed since 2012 (noisy miner).
    • Introduced pests, especially foxes and cats, have the greatest impact on native fauna.
    • Two new invasive species incursions have been reported since 2012 (red imported fire ants, tilapia).
    • Cane toads are considered an emerging species of concern, with several populations established. The invasion and establishment of the cane toad were listed under the Threatened Species Conservation Act 1995 (NSW) as a key threatening process in 2006.
    • Several emerging weed risks have recently been identified (orange hawkweed, mouse-ear hawkweed, sea spurge).
    • Pathogens and diseases are an emerging threat.
  • Assessment grade and adequacy of information:
    • Number of new invasive species detected: status—moderate; trend—stable; information availability—limited.
    • Spread of emerging invasive species: status—moderate; trend—increasing impact; information availability—limited.
    • Impact of widespread invasive species: status—poor; trend—stable; information availability—reasonable.

Queensland

  • Key pressures:
    • Sixty-eight major threats have been identified that affect Queensland threatened fauna. The threats affecting the most species are clearing of vegetation, inappropriate fire regimes and inappropriate grazing regimes.
    • Land clearing for pasture is the greatest pressure on threatened flora and fauna, and affects the eastern coastal bioregions at a higher rate; clearing has almost doubled since 2011–12.
    • Fragmentation is another key pressure; eastern bioregions—in particular, south-east Queensland—are the most heavily fragmented and prone to further degradation because they are close to cleared land.
    • Introduced pest animals place considerable pressure on Queensland’s native biodiversity. Negative environmental impacts include
      • predation on native fauna—foxes and feral cats have been implicated in the decline or extinction of native species
      • destruction of habitats and natural resources, including reduced water quality, increased soil erosion and land degradation, and destruction of native plants that provide food and shelter to native species
      • competition with native animals for food and shelter
      • disease, poisoning or injury to native animals—a decline of native predators has been attributed to poisoning from cane toads.
    • Invasive non-native plants (weeds) are widespread across Queensland, and have the potential to degrade natural vegetation and affect biodiversity.
  • Assessment grade and adequacy of information:
    • Knowledge of threats facing fauna—good; knowledge of invasive flora—moderate; knowledge of fragmentation—moderate.

Victoria

  • Key pressures:
    • For threatened species, key threatening processes are
      • habitat loss (affecting 109 species)
      • weed invasion (108 species)
      • grazing (99 species)
      • inappropriate fire regimes (63 species).
    • Key pressures for fauna species include
      • population fragmentation, leading to poor population viability, in part caused by habitat loss and fragmentation
      • predation by introduced species (e.g. foxes, feral cats, wild dogs)
      • competition for resources with introduced species.
    • Salvage logging of fire-affected dead trees has increased in the past 5 years in response to large fires; this can be detrimental to fauna by removing important habitat.
  • Assessment grade and adequacy of information:
    • No assessment provided.

South Australia

  • Key pressures:
    • Illegal land clearing is increasing.
    • The number, distribution and abundance of most pest plants, pest animals and diseases are increasing; the numbers of weeds, marine pests, aquatic pests and native plant diseases are increasing; the number of terrestrial vertebrate pests is steady; and the number of wildlife diseases is unknown.
    • Several weeds (gorse, blackberry) and 1 pest (feral camels) have decreased in distribution and abundance.
    • Some aquatic pests are increasing and some are decreasing, although the distribution and abundance of most aquatic pests are unknown.
    • Climate change has altered fire regimes.
    • Diseases are increasing (chytridiomycosis in amphibians, sarcoptic mange and alkaloid toxicity in wombats, psittacine beak and feather disease in parrots, blindness in kangaroos, chlamydia in koalas).
    • Phytophthora (causing rootrot and dieback in plants) is becoming more widespread.
  • Assessment grade and adequacy of information:
    • Introduced species: status—very poor; trend—deteriorating; confidence—low. Confidence in the assessment of trends of introduced species is limited because of a lack of evidence or consensus.
    • Insufficient data exist about the abundance and trends of aquatic pests.
    • The extent of disease in native fauna is largely unknown.

Western Australia

  • Key pressures:
    • Habitat loss or modification is resulting from introduced plants (weeds) or plant diseases, vegetation clearing, fragmentation and edge effects, altered fire regimes, or altered hydrological regimes, including salinity and acidification.
    • Introduced or feral animals cause a range of pressures on biodiversity, including
      • predation (e.g. foxes, rats, feral cats)
      • competition for food and/or habitats (e.g. camels, donkeys, goats, rabbits, feral cattle)
      • ingestion (e.g. cane toads).
    • Emerging plant diseases include
      • phytophthora dieback
      • canker
      • myrtle rust.
    • The changing climate is also bringing a range of pressures—in particular, the drying climate, such as in the south-west, is affecting a range of species.
  • Assessment grade and adequacy of information
    • No assessment provided.

Tasmania

  • Key pressures:
    • Vegetation clearance has predominantly been for dairy farming and cropping, with plantation clearing markedly reduced since 2010. Other pressures are fire and diseases (e.g. myrtle rust, phytophthora dieback).
    • Clearance and degradation of habitat (vegetation, soil, hydrology) have been because of
      • residential development
      • agricultural and forestry activities (clearance, dams)
      • hydro-electrical requirements
      • expansion of irrigation schemes
      • inappropriate fire regimes (frequency, intensity), which are expected to worsen with climate change.
    • Introduced species and weed invasion affect native species.
    • Drought has directly affected biodiversity and has also increased the browsing pressure from native animals.
    • A range of unpredictable threats to rare species exist.
    • Climate-induced change in the marine environment is affecting
      • ocean chemistry
      • food availability
      • foraging areas (changing temperatures and currents).
  • Assessment grade and adequacy of information:
    • No assessment provided.

Northern Territory

  • Key pressures:
    • In most terrestrial environments are, the key pressures are;
      • altered fire regimes, particularly more frequent, intense and/or extensive fires
      • habitat degradation by large feral herbivores and pigs
      • predation by predators (feral cats and foxes)
      • habitat modification by major environmental weeds
      • cane toads
  • The relative importance of these pressures varies regionally and for different biota; significant interactions between pressures are increasingly being recognised, with important implications for management.
  • The extent of clearing and fragmentation of native vegetation is relatively small, but is a significant pressure in the Greater Darwin region and Daly River catchment.
  • A significant and well-quantified increase in the extent and/or severity of some threats has been seen in the past decade, including gamba grass in the north-western Northern Territory and feral buffalo in Arnhem Land.
  • The density of feral camels in the territory has been greatly reduced as a result of the Australian Feral Camel Management Project between 2009 and 2014.
  • Management or containment of some weed and pest ant species has been effective at local or catchment scales.
  • Landscape-scale fire management for greenhouse gas abatement (‘savanna burning’), primarily on Indigenous-managed lands in the north of the Northern Territory, has ameliorated damaging fire regimes in some areas (notably western Arnhem Land).
  • Some new pathogens have recently emerged (e.g. myrtle rust), with uncertain impacts on native biota.
  • Sea level rise, saltwater intrusion and severe weather events (ultimately caused by climate change) are increasingly severe pressures on coastal environments, particularly floodplains. Recent extensive dieback of mangroves is likely linked to climate change. Climate change impacts on marine environments and biota are very poorly known.
  • Assessment grade and adequacy of information:
    • No systematic remote monitoring of vegetation clearing currently exists.
    • Recent quantitative data are available about the extent and density of some feral animal species, either for the entire territory (camels) or for some regions (feral buffalo, feral horses).
    • Very poor data exist for the density distribution of feral cats, although techniques are currently being developed to monitor cat occupancy and abundance.
    • Generally good data are available about the spatial extent of major weed species.
    • Good spatial data are available about the annual extent of fire throughout the territory.
Cresswell ID, Murphy H (2016). Biodiversity: Jurisdictional reporting on pressures. In: Australia state of the environment 2016, Australian Government Department of the Environment and Energy, Canberra, https://soe.environment.gov.au/theme/biodiversity/topic/2016/jurisdictional-reporting-pressures, DOI 10.4226/94/58b65ac828812