Document ID: chunk:federal_register_of_legislation:F2019L00106:body:0:p11
Version: federal_register_of_legislation:F2019L00106
Segment Type: other
Provision Reference: 
Character Range: 29497–32375

m (usually 0.4–0.6 m) and water velocity was between 0.3–0.6 m/sec. Brumley et al. (1987) also found that habitat areas often have a pool (usually 15–30 m long and at least 1.5 m deep) immediately upstream and fast-flowing broken water immediately downstream. Within Seven Creeks, the species still occurs in the middle reaches from below Polly McQuinns Weir downstream to habitats below Gooram Falls (ARI pers. comm., 2017), and individuals are thought to be in good condition in areas where deep refuge habitat from predators was accessible.. Upstream of Polly McQuinns Weir, the species is likely to be extinct (Stoessel 2009). Until recently, adults in the Cotter River catchment in the Australian Capital Territory principally resided within Cotter Reservoir rather than the river (Ebner & Lintermans 2007; Ebner et al., 2008) but that was probably due to the lack of riverine habitat available to the species given the barrier posed by Vanitys Crossing (Broadhurst et al., 2012; 2013). Within the Cotter Reservoir adults use emergent macrophytes for shelter and juveniles are associated with rock piles (Ebner & Lintermans 2007).
Preferred juvenile habitat in rivers is not well documented. Juveniles of 10–30 mm length inhabit pools in the Cotter River and are benthic and/or semi-pelagic during the day and inactive at night (Ebner & Lintermans 2007; Ebner et al., 2008; 2009; Broadhurst et al., 2012).
Reflecting of its records in the uppermost and high altitudinal parts of the Murray-Darling catchments it once occurred (Trueman 2011), Macquarie perch can tolerate relatively cold water temperatures. It has been measured to be living in temperatures as low as at least 4°C in in the Cotter River in the Australian Capital Territory (ACT Gov pers. comm., 2017) and living in the upper Murrumbidgee River at Kissops Flat where water temperatures regularly drop under 4°C in winter (Lintermans unpub. data., cited in Lintermans pers. comm., 2017).
A recent study of the Macquarie perch population in Lake Dartmouth found that growth and recruitment were highest during years of refilling, when amongst other variables, water temperatures were low. The study considered the influence of low water temperatures on high growth not surprising given the species' natural occupancy of cool, upland streams (Tonkin et al., 2014). Observational evidence indicates that the Macquarie perch in aquaria show signs of severe illness or stress once temperatures reach 26°C or above (Lintermans unpub. data, cited in Lintermans pers. comm., 2017), consistent with observations of broodstock in ponds perishing when water temperatures exceeded 27°C (Trueman pers. comm., cited in Trueman 2007).
The species requires a temperature rise in spring months, generally to at least 16°C for spawning to occur, but it is possible that they can spawn at lower temperatures (Cadwallader & Rogan