myna poses a serious threat (such that it has been listed in the World Conservation Union's world's 100 worst invasive species). The bird has caused human health concerns due to the spread of mites and disease and it has also been known to force native birds and their eggs from their nests. The rock pigeon in particular has acidic faeces and can damage human property, including historic stone buildings. Control Historically, control programs have struggled to curb the expansion and proliferation of invasive bird populations in Australia. A new program in Canberra has reversed this trend regarding mynas. Since 2006 the Canberra Indian Myna Action Group (CIMAG) has implemented an effective control scheme, based upon large-scale trapping conducted by volunteers. As of June 2013 the Action Group has recorded over 45,000 myna captures in the Canberra region since 2006. This has reduced the myna's prevalence in the Canberra region from a ranking of third most prevalent bird species in 2006, to twentieth in 2012. This has correlated with anecdotal evidence of increased nesting activity and prevalence of native species in the Canberra region. Other volunteer organisations in Australia have begun to adopt the CIMAG model with similar success. Starlings and sparrows are currently closely monitored in south-eastern Western Australia. Despite the number of rock pigeons, many people continue to feed the birds bread crumbs and assist them to breed in great numbers. It is not illegal to feed pigeons in Australia, and many local proposals to cull pigeons have been rejected. Programs promoting indigenous plantations to attract native birds are an alternative method of promoting native species rejuvenation. Invasive freshwater fish species Invasive freshwater fish species in Australia include carp, brown trout, rainbow trout, redfin perch, mosquitofish (Gambusia spp), weather loach, and spotted tilapia among others. Some introduced freshwater fish species have had devastating impacts on Australia's endemic freshwater fish species and other native aquatic life. For example, in much of south eastern Australia's freshwater systems introduced carp (often incorrectly called "European" carp) dominate the lowland reaches, while introduced trout species almost completely dominate the upland reaches. While the damaging impact of carp is well recognised, little in the way of control measures have been employed to control their spread. Their ability to colonise almost any body of water, even those previously considered to be beyond their physical tolerances, is now well established. Invasive marine species A number of marine