Progressing our understanding of Rhinonicteris over the past 18 years - PowerPoint PPT Presentation

Progressing our understanding of Rhinonicteris over the past 18 years Dr Kyle Armstrong

How far we have come Postgraduate Research at UWA • Field surveys – distribution, habitat use and spatial pop structure • Phylogeographic and taxonomic comparisons Rise of acoustic surveys with AnaBat • Project specific surveys • Monitoring studies Reinventing acoustic surveys with ‘full spectrum’ • Balancing expediency and accuracy in analysis • Automated and semi-automated approaches • New standards needed Mixing research with mining • Population genetic studies Contributing to conservation and management • BAP, MAP, SPRAT, Commonwealth survey guidelines Postdoctoral work • Resolving taxonomic status  ABRS

Postgraduate Research Field surveys – distribution, habitat use and spatial pop structure (Armstrong 2000, 2001, 2003; Armstrong and Anstee 2000) Data from Armstrong 2003 PhD thesis; KN Armstrong and Gaia Resources unpub ms

Postgraduate Research • Pilbara high freq phonic type ( Armstrong and Coles 2007, Armstrong and Kerry 2011 ) • Some subtle morphological differences ( Armstrong 2002, 2005 ) • Previous genetic work (mtDNA) showed some genetic divergence ( Armstrong 2006 ) Taxonomy • Bat Action Plan, EPBC Listing

Rise of acoustic surveys with AnaBat • First comprehensive acoustic surveys were undertaken for several clients between 2001 – 2003 by Biota Environmental Sciences • AnaBat-based surveys became the standard in the following years • Monitoring studies with BHP Billiton, Atlas Iron, Rio Tinto Iron Ore based on comprehensive standardised approach • Monitoring during drilling programmes (Armstrong 2010)

Inferring usage from activity Possible roosting – peaks after dusk, much activity before dawn. High importance. Permanent diurnal roost, transient diurnal roost, maternity roost. Drinking? – visiting pool before foraging, before roosting. Important for maintaining presence, useful for monitoring. Not necessarily a diurnal roost. Night roost – low level visitation during the night, refuge for resting? Lowest activity. Less critical habitat, but of value. Night roost.

Reinventing acoustic surveys with ‘full spectrum’ Advantages • Good mic zone of reception, esp. for ultra-high frequency bats • Greater sensitivity, all things considered • Better resolution of calls for Rhinonicteris and Macroderma, harmonics for others, some still difficult • Several brands and models available • Lots of functionality with accompanying software Challenges • Many gigabytes of data to analyse in short timeframes, similar budget expectation. Balancing expediency and accuracy in analysis • Careful consideration of the effects of • sensitivity settings,  thresholding and parsing • filter use,  file scrubbers, • format conversion, and • other automated processes including for species-level identification. • New standards needed  ABS • Principles of good survey design

Auto-manual hybrid process • Download and convert WAC to WAV • SoundID – non-trivial • Visual Basic script in Excel for data management • Manual checking of each marked WAV for target • Compile and graph

Automated analysis in SoundID

Example monitoring project (Atlas Iron) • About 750 GB (3 weeks from 6 units) • 290,532 WAVs (5 sec or less) • 519,803 hits (above 100 kHz) • 520 matches • 244 WAVs with matches • 100 WAVs with target • CPU time 179 hours = 22 office days • More for a person

Small benchmark test • 16,000 WAV files • Manual searching for Rhinonicteris • Gave 76 WAV, 0% false neg/pos • Automated SoundID analysis 39% detection • Convert to ZCA 29% detection • Improved with a new SoundID version, improved optimisation, 70% detection • But auto detection rate back to 30% (13,000 file test set) in open habitat rather than cave entrance • ZCA from Kaleidoscope had greater detection than SoundID. But not appropriate for cave entrances. • Similar patterns between WAV and ZCA, both better than recording in ZCA with AnaBat equipment.

Mixing research with mining • Connectedness of colonies, population level genetic diversity • Good genetic diversity, elevated inbreeding only in peripatric West Pilbara group • MtDNA suggests high female philoptary, with two subpops • Microsatellites suggest males move throughout the Pilbara, responsible gene flow • Demonstrated opportunity for avoidance of human disturbances (low level chronic, non-catastrophic) BUT females less likely to move

What we still face • How do we deal with uncertainty? • What detection methods are appropriate? • How can we maintain rigour in acoustic surveys? • How to overcome practical constraints to info gathering? • How can we confirm roosts? • How do we place a value on roosts? • How do we protect colonies with large aggregations? • How do we ensure there are no concomitant impacts? • How important is foraging habitat? • How far can they move? And is this useful info? • How close can mining come to a roost? Intractable? • What should monitoring achieve? Triggers? Contingencies? • What should we do when a roost coincides with an ore body?

Key threatening processes Mammal Action Plan Vulnerable A3c; D2 Area of occupancy <10 km2, declining Unknown number of mature individuals 6-7 subpopulations  actually just one population, two subpops … Key threats include: • Deterioration of old mines ( includes flooding) • Human disturbance of roosts • Habitat loss (caves, mines) Plus • Roadkill near roosts • Concomitant effects

Conservation objectives (draft Mammal Action Plan) 1. Maintain viability of colonies throughout the population 2. Review and collate unpublished information collected by mining companies 3. Develop a regional management plan that prevents extensive destruction of roost sites 4. Acquire/manage land for conservation purposes where significant roosts occur 5. Encourage non-invasive or low impact activities that confirm the diurnal use of potential roost sites following acoustic detection at cave sites 6. Ensure any exploratory surveys, monitoring programmes and research projects do not introduce disturbance

Plugging the gaps – highest priority needs From BAP, SPRAT, MAP, Comm Cons Advice, my more recent thoughts Research • Estimating abundance, studies of social behaviour, diet – PhD • Complete taxonomy – being undertaken currently Proactive and focussed management • Roost protection, esp. old disused mines • Develop a set of standard guidelines for mining proponents to follow, flowchart, regional management plan (incl ghost bat), collated information, update Commonwealth documents • Long term monitoring of known roosts, and engagement with private programmes Rigorous consultancy work • Non-invasive surveys with appropriate gear and visitation • Roost confirmation as a standard survey approach • Artificial roost experiments • Long term monitoring where appropriate

Regional management plan • summary of what is known based on published science and observations with good evidence in unpublished reports. • flowchart for approach , provide a standardised path for developers to follow • management options, guidance for offsets • buffer zone size guidance • guidance for monitoring projects - design constraints, triggers and appropriate contingency responses • artificial habitat guidance note - when and how it would be appropriate, and a strategy outline • monitoring programme at key sites to assess concurrent impacts, to establish baseline and maintain vigilance

Effect of ‘non - invasive’ monitoring Let’s be careful when we think about research topics. Is the knowledge likely to have a net positive effect?