Jessica Oates and Brent Johnson The Quolls of Poondano: A Case Study

Background The project targets Channel Iron Deposits (CID) that are expressed as both bedded formations (Poondano South West) and exposed mesa formations (Poondano Central). Small 4.2 million tonne resource. Fauna assessment of the Poondano area by Bamford Consulting in Northern quolls were detected on Poondano Central (Outback Ecology 2009a). Rapallo undertook a targeted trapping program across Poondano Central and Poondano West (Rapallo 2010). Referred to the Department of Sustainability, Environment, Population, Water and Communities and listed as a controlled action. Further trapping by Rapallo in April 2011, which focused on understanding the regional distribution of the northern quoll (Rapallo 2011). Genetic investigations undertaken: Population structure analysis shows that they clearly group well within a ‘Pilbara’ cluster, undifferentiated from animals that have been sampled from the Pilbara previously. Mining at Poondano Central commenced October Approval Condition required development of a Fauna Management Plan to manage potential impacts from mining. Monitoring survey in July 2012 for the northern quoll across the impact and control sites (Rapallo 2012). Northern quolls were captured at all trapping locations, with a total of 69 individuals recorded results indicated that the population surrounding Poondano Iron Ore Project was robust, although displacement was observed at Poondano Central. Monitoring and radio-tracking May – July 2013 undertaken by Astron Environmental Services.

Poondano Mesa

Poondano Central

Poondano West

2013 Monitoring A similar methodology to Rapallo (2012) was employed for the northern quoll trapping program. A total of 100 cage traps at eight sites were monitored for between 4 and 7 nights, resulting in a total of 610 trap nights. Trap sites were re-established at the same sites two new ‘control’ sites.

Study Area

Data Analysis A spatially explicit capture-recapture framework enabled explicit modelling of animal (e.g. sex, maturity, learning), trap (e.g. distance from impact, habitat zone, trap type) and temporal (e.g. seasonal differences) effects on the distribution of a spatially heterogeneous population. secr package in R. The basic model focuses on three parameters: – population density – probability of detection per night – a scale parameter describing the home range extent of the ‘average’ animal. These population parameters were estimated individually for each year and for each population site surveyed.

Trapping Results SiteNo. Individual QuollsNo. Total CapturesTrap Success (%)Male : Female Ratio Poondano Central :1 Poondano West :1 Control East :1 Control West :1 Granite Outcrop :1 Northern Outcrop :1 Poondano East :1 Southern Granites :1 TOTAL %0.83:1

YearSite Density Estimate (no. quolls per ha) Detection ProbabilityPopulation Estimate 2010 Poondano West Poondano Central Poondano West Poondano Central Granite Outcrop Northern Outcrop Poondano West Poondano Central Granite Outcrop Northern Outcrop Southern Granites Poondano East Poondano West Poondano Central Granite Outcrop Northern Outcrop Southern Granites Poondano East Control East0.1504NA3 Control West The population parameters of density, detectability and home range extent of the average animal were further modelled as a function of both sex of the individual animal (male or female) and or behaviour of the individual animal (i.e. learning). No consistent influence of any of these factors on any of the population parameters when compared across mesas and years, as measured by the Akaike Information Criterion (AIC).

Quoll population estimates (± SE) for each monitoring site between 2010 and 2013 PW – Poondano West, PC – Poondano Central, GO – Granite Outcrop, NO – Northern Outcrop, SG – Southern Granites, PE – Poondano East Activity at Poondano West Mining at Poondano Central

Density, detectability and movement extent were also modelled as a function of distance from disturbance. Distance from Poondano West, which is considered to be currently active mining Distance from Poondano Central, which is considered to be previously mined. Quoll numbers were not influenced by distance to current or previous disturbance

Individual Movements of Quolls

Summary of Population Modelling Results Current data suggests that the northern quoll population within and surrounding the Poondano Iron Ore Project remains stable and robust. Short-term movement (or displacement) of quolls related to disturbance from mining activities. High site fidelity to rocky habitats – no use of riparian habitats. Number of other factors that are considered likely to affect the : – overall population numbers Rainfall Resource availability Fire – spatial distribution of quolls and re-colonisation of previously disturbed areas Elevation Slope Refuge (cave/crevice) retention and boulder size Landform Vegetation

Refuge Preference Zones of high refuge opportunity No recorded use of hollows or burrows Strong preference for rock caves, crevices & boulder piles Mining infrastructure is utilised – buildings, laydowns, waste rock dumps, vehicles and machinery Strong site fidelity shown by females and some males Movement between mesas & granite outcrops mainly demonstrated by males 2 – 3 km movements common Home range data yet to be analysed

Mining Activity and Interactions

Rehabilitation (commencing 2013)

Rough is good! Plan prior to mining commencement Retain material Heaps are better than level spread Provide clear prescriptions (SWPs) and training to machine operators

Threats Habitat loss – Foraging – Refugia Human interactions Feral predators Cane toads in Petermarer Creek?

Summary of Findings This is a significant northern quoll population The population remains robust Predation not recorded in radiotracking study High site fidelity displayed Strong refuge preference for rocky habitat over riparian Mining infrastructure needs to be considerable distance from preferred habitat to prevent interactions Management and staff awareness is essential Housekeeping needs to be maintained Correctly rehabilitated sites will be utilised Clear prescription for rehab needs to be written prior to mining activities

Recommendation for Research at Poondano Value add Collect and analyse a number of habitat covariates from monitoring sites so that these can be linked to the spatial distribution of quolls, including landform, geology, elevation, slope, aspect, measure of boulder size, vegetation. Collect and analyse a number of aspatial trip descriptors such as a drought index, rainfall preceding the monitoring trip, Normalised Difference Vegetation Index (NDVI) value for the project area, so that these can be linked to the temporal changes in quoll numbers. Plus Monitoring of rehabilitated areas to assess re-colonisation trends and requirements (Adaptive management?) Survey of outlying mesas and outcrops to broaden regional knowledge.

Acknowledgements: Polaris Metals Pty Ltd Astron Team Questions?