Document ID: chunk:federal_register_of_legislation:F2024L01094:body:0:p21
Version: federal_register_of_legislation:F2024L01094
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Character Range: 62440–65511

degraded habitats they can become the subordinate one (Futuyma & Moreno 1988; Kassen 2002).

3.2.7 Competition for nest hollows
Striated pardalotes and tree martins compete with forty-spotted pardalotes for nest cavities with small entrances and deep chambers, often evicting them from their nests even after eggs have been laid. Edworthy (2016a) found that 10% of forty-spotted pardalote nests were usurped by striated pardalotes but found no cases of forty-spotted pardalotes evicting striated pardalotes from nests. Tree martins also usurp nest boxes used by forty-spotted pardalotes. Forty-spotted pardalotes often spend many days trying to defend their nests from these competitors without success (T Cochran & A Hingston 2022. pers comm 10 January). Such competition reduces breeding opportunities for forty-spotted pardalotes, resulting in energy loss, delayed breeding, nest takeover, and loss of eggs (Edworthy 2016a). Additionally, striated pardalotes and tree martins are relatively insensitive to habitat disturbance and may have a competitive advantage over forty-spotted pardalotes in altered habitats (Bryant 2010).

3.2.8 Competition by aggressive native birds
The noisy miner is a native species that often aggressively excludes other small woodland birds from remnant vegetation (Willson & Bignall 2009). Noisy miners have benefited from landscape-scale clearing and fragmentation, possibly at the expense of forty-spotted pardalotes (Bryant 2010). The species typically dominates open eucalypt woodland remnants (such as tree corridors and clumps of paddock trees) on farms, especially those lacking a shrubby understorey (Crates et al. 2018). Although noisy miners do not currently co‐occur with forty-spotted pardalotes, much of Maria Island, Bruny Island and the Tinderbox Peninsula is climatically suitable for noisy miners (Webb et al. 2019). Thus, local scale noisy miner control programs at critical breeding sites may be needed in the future.

3.2.9 Predation by introduced species
The Krefft's glider is non-native to mainland Tasmania (Gunn 1851; Rounsevell et al. 1991; Lindenmayer 2002; Hui 2006; Campbell et al. 2018) and is a known predator of Lathamus discolor (swift parrot) adult females, nestlings, and eggs within nest hollows (Stojanovic et al. 2014; Heinsohn et al. 2015). Hence, it is possible that forty-spotted pardalotes nesting on the mainland of Tasmania are also similarly affected if using hollows with entrances large enough to permit access by gliders. Such an impact could explain why forty-spotted pardalotes have largely disappeared from mainland Tasmania while persisting on the glider-free Maria and Bruny Islands. The black rat (Rattus rattus) is a potential predator of the forty-spotted pardalote, as it is capable of climbing into trees and depredating bird nests (Smith et al. 2016).

Additionally, there has been a significant change in bird populations across Australia (BirdLife Australia 2015), and there are knowledge gaps in terms of the impacts of these changes on predation and competition of native and