Lake Eyre Basin Rivers 70 Populations of waterbirds, flock bronzewings (Phaps histrionica), frogs, butterflies, dragonflies and brightly coloured insect pollinators also increased with the rains, often irrupting spectacularly. Increasing populations of plague locusts (Chortoicetes terminifera), introduced house mice (Mus musculus) and native long-haired rats (Rattus villosissimus) exhibited similar patterns, damaging agricultural infrastructure and livestock pastures. This proliferation of prey brings increases in several species of elapid snakes (e.g. western brown snake (Pseudonaja nuchalis), ringed brown snake (P. modesta) and king brown or mulga snake (Pseudechis australis)) that feed on the many mammals and frogs. Feral cats (Felis catus), red foxes (Vulpes vulpes) and dingoes (Canis dingo) also increase in numbers during boom periods (Dickman et al. 2014). Heavy rainfall also increases weeds (e.g. buffel grass (Cenchrus ciliaris), athel pine (Tamarix aphylla)) and other vertebrate pests (e.g. cane toads (Rhinella marina), feral pigs (Sus scrofa)). With more vegetation growth and spread, fire risk also increases. Fires in the study region are estimated to return to the same patch about every 26 years (Greenville et al. 2009), but this may reduce with future climate changes (Low 2011). Potential consequences of irrigation and mining developments The boom and bust dynamic that prevails in the desert channels environment and the Lake Eyre Basin more broadly will be affected by developments that destroy habitats and these cycles. For example, coal seam gas contaminates groundwater (Osborne 2012), damaging aquatic animals and potentially polluting surface artesian waters (GABCC 2009). Animals can fall into uncapped drill holes where exploration is unregulated (Pedler 2010), while surface mining activities and their associated infrastructure can remove large tracts of habitat (Andersen et al. 2014). More generally, irrigation and mining developments increase human habitation, requiring water and waste disposal operations which can affect populations of plants, animals and other organisms. For example, development of mine sites can artificially inflate predator numbers, change home-range sizes and indirectly affect co-occurring species through changes in levels of predation or competition (Newsome et al. 2013 Newsome et al. 2015). In addition, increased roads, even if unsealed, and other transport infrastructure increase weeds and feral animals, especially foxes and feral cats that preferably use vehicle tracks (Mahon et al. 1998). We focus on two potential scenarios, assuming current development recommendations (Northern Australia Land and Water Taskforce 2009), which are irrigation developments, mining modification of landscapes with removal of native vegetation for roads and mine infrastructure, and depletion of ground waters and surface water flows. We acknowledge that global environmental change will very likely further alter these scenarios and increase uncertainty in outcomes, both for development options and environmental degradation. This uncertainty emphasises the need to critically evaluate evidence for the success of any proposed scheme before it goes ahead. Scenario 1: Fixation of boom-period conditions Increased irrigation will affect natural boom and bust cycles, emulating heavy onsite rainfall or flooding events. Persistent water in the landscape in the form of increased low flows and
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