In Australia, invasive species have been recognized one of the most serious threats to biodiversity. According to Environment Protection and Biodiversity Conservation Act 1999 (EPBC), invasive species are the primary cause of animal extinctions in Australia. Invasive species cause about three-quarters of the vertebrate animals and one-third of the …show more content…
combined flora and fauna species extinctions in the past two centuries (about 22 species of mammals, 13 island birds, 4-6 frogs and 2 endemic rodent species). However, extinctions of invertebrate animals and threatened species have not been comprehensively identified, the total number of extinctions species cause by the invasive species would be much large.
Invasive species of significant concern include: European Rabbit (Oryctolagus cuniculus), European Red Fox (Vulpes vulpes), Feral Cats (Felis catus) and Cane Toad (Bufo marinus). Those are recognises as threats to native species under the EPBC Act.
Red fox had introduced into Australia in about 1855 for fox hunting.
Red foxes don’t have much natural predators in Australia, most death only occur due to human activities or drought. In addition, red fox is a predator of variety species. They played a decisive role in the decline and extinctions of small and medium sized species. A brief review by the department of the Environment, Water, Heritage and the Arts (DEWHA) (2008) identified that red fox are considered a treat to 48 mammals, 14 birds, 12 reptiles and 2 amphibians. Furthermore, as they also consume a range of fruits and carrions. These allow them to out-compete Australia’s native organisms for food. Now red fox had spread across Australia and the presently inhabit is about 76% of the continent (West, 2008, p. …show more content…
34).
Invasive animals can also act as a carrier of same common diseases as domestic animals. For example, fox are potential carriers of rabies. Rabies can be transmitted to human and between animals through the saliva of the animals. Once spread, it would be very difficult to control. (Australian Government, 2013, para 4)
Climate change or natural disaster
According to Dr Belinda Reyers, a Chief Scientist at the Council for Scientificand Industrial Research (CSIR), there is a close interaction between the biosphere integrity and the climate change. The average temperature of the Earth surface in Australia has risen 0.7 – 0.9℃ over the past 100 years, and according to the inter-governmental Panel on Climate Change (IPCC) project, the temperature in 2100 will rise about 1.6-4.3 ℃ compare to 1850 -1900 baseline. The increase in temperature will affect the biodiversity in different ways.
Effect on species
The first things that the climate effect on the species are the species distributions.
Due to the temperature increase, species have to migrate to higher elevations or latitudes to areas with preferred climate. However migration might not be possible for some species, due to the geographical, human actives or exist of competition species. Furthermore, climate change might benefit to some introduced species, such as dingo. Dingo is classified as the Australia’s largest land predator. Sciences predict that the distribution and abundance of dingo will increase because of the climate change. This expand their prey base and will be implications for either native or invasive
species.
Phenological changes is another other impact that climate change effect species, such as the timing of migration and breeding. The advance of spring lead to many birds migrate in the early spring and late autumn. It also extended some species breeding seasons. However, this might not benefit to the ecosystem as the interaction between species are important. If two interacting species responds differently to the climate change, it could create a mismatch between species, such as the breeding time of bird advances faster than the peak abundance of its prey.