Threats to wildlife
Threatening processes are practices that are reducing or will reduce the biodiversity and ecological integrity of a regional ecosystem and its wildlife. Processes that are threats to wildlife in Queensland include:
Loss of natural habitat through land clearing for pastoral purposes, urban development and agriculture can threaten native wildlife and their habitat.
A scientific review of the impacts of land clearing on threatened species in Queensland 2017 provides evidence that land clearing causes species decline and habitat loss, exacerbates other threatening processes, and reduces the resilience of threatened species to survive future challenges such as climate change.
Inappropriate grazing and fire regimes
Grazing pressure from domestic stock and introduced animals (such as rabbits) can have a negative impact on habitat of native animals. Changes in the frequency and intensity of fire can cause wildlife populations to decline. Some species depend on a suitable fire regime for successful regeneration and survival.
Invasive plants and animals
The global movement of goods and people are directly contributing to the introduction of plants and animals to areas where they do not naturally occur. These species taken to new environments may fail to survive but some thrive and become invasive. This process, together with habitat destruction, has been a major cause of extinction of Australian native species in the past few hundred years. Invasive species causing harm to the environment, biodiversity, human health or productivity are declared under Queensland legislation and are subject to a range of control actions, from preventing spread to eradication.
Invasive species include:
- introduced marine pests
- diseases, fungi and parasites
Introduced pest animals place considerable pressure on native wildlife. While some impacts have been well documented, the true impact of invasive animals on Queensland's environment is unknown and difficult to quantify. Invasive species such as foxes and feral cats, prey on native fauna and have been implicated in the decline or extinction of at least 17 native species. Feral pig predation of marine turtle nests is one of the main threats facing marine turtle populations in Queensland. Cane toads compete for food, shelter and breeding sites with native animals. This is thought to be an important factor in the decline of many native animals, particularly the decline in number of some native frogs. Pest fish, such as carp, tilapia and mosquito fish, compete for resources, degrade fish habitat, predate on native fish species and introduce and spread diseases and parasites.
The Australian Government has listed the impacts of some invasive species as a key threatening process under the Environment Protection and Biodiversity Act 1999 (EBPC Act) and threat abatement plans have been developed.
Find out more information on particular invasive animals in Queensland.
Weeds can degrade native vegetation and have a detrimental impact on biodiversity.
The loss and degradation of native plant and animal habitat by invasion of escaped garden plants, including aquatic plants is listed as a key threatened process and has had a listing advice developed.
Aquarium and other aquatic plants can carry pathogens that can devastate native populations of plants and animals.
More information about invasive plants can be found on the Business Queensland website.
There are a number of non-native marine pests (reported in Australian waters most of which were introduced accidentally by shipping and aquaculture activities. Some, including several crabs, mussels, seastars and seaweeds have been found to have a significant impact on marine ecosystems.
Diseases, fungi and parasites
Diseases, fungi and parasites can reduce the ability of native plant and animal species to reproduce or survive. Due to their reduced or restricted populations and the impacts of other threatening processes, threatened species can be particularly vulnerable to introduced diseases, fungi and parasites. Some of the diseases, fungi and parasites currently of concern because of their impact on native species include:
- Psittacine beak and feather disease (psittacine circoviral disease) impacting on native parrots
- Chytrid amphibian fungus – Chytridiomycosis impacting on native frogs
- Phytophthora cinnamomi disease affecting many native plants
- Myrtle rust Puccinia psidii
Collecting native plants and plant parts is another threat to some of our native plants. Under the Nature Conservation Act 1992 and Nature Conservation (Wildlife) Regulation 1994, the harvesting and sale of native plants and plant parts are closely regulated.
Some ferns, tree ferns, cycads and orchids are seriously threatened by collecting. Even common plants like grasstrees and staghorns are at risk. Individual plants can be damaged when stems, fruits and flowers are removed. Collecting a plant's seeds reduces the prospects for successful regeneration.