Boffa Miskell Ltd | Pest Animal Management Plan | Wharekirauponga Compensation Package | 30 May 2022 5 protection areas have frequently been well over the 5% tracking tunnel index (TTI) targets (sometimes up to 60% TTI; Easton, 2021), meaning these frogs have still been subject to predation impacts. Native frog populations can therefore be expected to respond positively to intensive animal pest management (M. Baber et al., 2006), and as such they may also be a useful bio-indicator to measure the general success of mammalian pest control initiatives. Control of rats, mustelids, possums and feral cats will therefore have a direct and measurable positive impact on the frog population. Based on evidence from other pest control programmes around New Zealand, with effective pest control in place over the wider area, the population of Archey’s frogs could therefore be expected to increase between 2.3 and 4 x the current population over a period of 3-4 years (and possibly greater in subsequent years) (Table 2). Table 2. Summary of case studies of predator control impacts on frog populations. Note areas are approximations only, and some boundaries are not well-defined. Area Size Control programme Pest control targets Success rates for frogs References Kokako Management Area (KMA; Hunua Ranges) 850 ha Intensive bait stations and traps; aerial 1080 1% residual trap catch (RTC) for possums and 1% rat tracking index (RTI) for rats by 1 Nov each year Hochstetter’s frog abundance / person hour searched was significantly higher within the KMA, with a higher the proportion of juveniles in the KMA (21% inside c.f. 9% outside). • Innes et al. 1999 • Baber et al., 2008 • Baber et al., 2009 Maungatautari 3,363 ha Pest eradications and pest-proof fence (except mice) 0% (pest-free) except for mice) Fourfold increase in Hochstetter’s frog numbers between 2009 and 2012 from a very low initial density • Longson et al., 2017 Whareorino Initially 300ha, later in 2017 increased to 600ha Intensive ground-based rodent control programme using with anticoagulant rodenticides and five yearly aerial 1080 operations <3% for possums <5% TTI for rats 2.3 x increase in L. archeyi population numbers (Ramirez 2017), despite rodent densities sometimes reaching high levels. • Haigh et al., 2007 • Ramirez, 2017 • Pledger, 2011; Pledger 2013, Bridgman, 2015 (unpub DOC reports, cited in Ramirez, 2017) 1.6 Current pest densities and history of control Previous pest control in the Wharekirauponga / Otahu area has predominately consisted of aerial 1080 applications approximately every four years, with the last operation on 7 November
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