Koala Science

Survey Points South Coast-click map to access
Tree Index-click map to access
Habitat Suitability-click map to access
The team on site during plot survey July 2020
Koala mother and baby

Grant money awarded to Coastwatchers

Read article on grants award here

Red ironbark and spotted gum at Jingara Farm, Mogendoura 3.5 months after the fire

Wires funded Drone used to gather images

Lyrebird in recovering forest 6th March 2020. Photo courtesy Atlas of Life in the Coastal Wilderness.

EKP are involved in supporting the latest science in relation to Koalas and their habitat.

Find out the latest Koala News from ANU here Koala Science News: ANU fire impact

Advances in GIS (Geographic Information Systems) and publicly available data

Since 2012 when the Eurobodalla Koala Project generated its own habitat maps using costly ArcGIS software, powerful freeware has become available and we are now using QGIS.

Greatly improved maps and supporting datasets have also become publicly available through the NSW Government’s Koala Habitat Information Base at https://datasets.seed.nsw.gov.au/dataset/koala-habitat-information-base

The Project’s volunteer team has so far overlaid our Deua National Park plot survey coordinates on the SEED map layers for koala habitat suitability, a koala tree index and vegetation types.

This permits us to analyse and draw conclusions about the relationship between the map layers and what we found at close scale in the field. We can mediate this using the other research mentioned elsewhere in our website’s SCIENCE section, and by cross-referencing our findings with the NSW Government’s 2018 publication which updated koala use of tree species for all regions across the State.

The validity of our research can be scrutinised therefore, and there is the added advantage of contributing to, and helping validate the NSW Government’s own data.

Plot Surveys carried out July 2020

Data sheets relating to the plot surveys carried out in July 2020 can be found using this link – Plot Survey Data Link

What’s happening now – studying the Wamban-Nerrigundah corridor

The Eurobodalla Koalas project’s scientific priority for 2020 is to complete the ground-truthing of the forested patch between Wamban and Nerrigundah, which our previous research suggested is a potentially viable breeding corridor because of 2013 koala evidence at each end plus the presence of Eucalyptus globoidea, Angophora costata and other known browse species.

Commonwealth funding

For this work, the Commonwealth Government has granted $2,800 to The Coastwatchers Association Inc (matched in-kind by Coastwatchers) under the Communities Environment Program. This grant is for 4-wheel-drive hire to enable 10 close-scale plot surveys in what is officially called the Eurobodalla Koala Habitat and Occupancy Project, Gilmore Electorate.

The broad purpose of the grant is identification of koala habitat with a view to future koala population revival or reintroduction.

Fire and COVID-19

Although the grant was made beforehand, the severe fires of the 2019-2020 summer made this work all the more important, firstly as a contribution to the economic and social recovery of the Eurobodalla, and secondly for the scientific purpose of ascertaining the fires’ impact on the project’s Regularised Grid Based Spot Assessment Technique (RGBSAT) for individual plot analysis as well as the estimated survival and recovery rates of the broader habitat patch. These catastrophic fires burned most of the patch.

Fieldwork (the plot surveys) was postponed to allow community and agency contacts time to recover as well as access and safety reasons. Social distancing and travel restrictions associated with the COVID-19 virus pandemic added to the delay.

The plot surveys have now begun, but are being interrupted by inclement weather. Fortunately the Commonwealth has extended our reporting deadline to mid-2021, so we are confident about completing all surveys and publishing our findings in a full report by then.

Tree planting for encouraging koalas on farms a reference and abstract.

Biodiversity benefits are routinely cited as an outcome of planting trees on farms but there has been too little information to properly substantiate such claims. This study is among the first to examine the use of plantings by arboreal mammals. We examined an important inland koala population and its use of farm revegetation to determine: (1) if koalas use planted trees; (2) patch characteristics correlated with use/non-use by koalas; and, (3) contextual characteristics correlated with use/non-use. Surveys of koala dung, also known as scats or faecal pellets, were conducted under trees in 19 plantings. Fourteen showed signs of koalas and their pellets were recorded under 16 of the 25 tree taxa examined. All sizes and ages of trees were used, including the youngest plantings (six years). Considerable koala activity occurred in the various Eucalyptus species, but some tree species were not used. Koalas made substantial use of inland ironbark species, which are not listed as ‘koala food trees’ in government policy documents. Proximity to potential source populations of koalas was the strongest predictor of a planting being used, but this was further improved by including the age of the planting. There is extensive public funding available for restoration and land care activities. This study demonstrates that certain trees rapidly provide koala habitat when planted on farms and that the first priority should be restoring sites in close proximity to known koala populations. Tree species used should include local recognized food trees, as well as ironbarks and non-eucalyptus species that offer shelter. Rhind Susan G. , Ellis Murray V. , Smith Martin Lunney Daniel (2014) Do Koalas Phascolarctos cinereus use trees planted on farms? A case study from north-west New South Wales, Australia. Pacific Conservation Biology 20, 302-312. 

New additions to the data collection

Amended planning for the fieldwork has included additions to expected data collection such as the short and long-term impact of the fire on eucalypt recovery, whether thinning/thickening of shade or understory are permanent, the health of watercourses and soil nutrients after hot fire.

To support the fieldwork, volunteers are collecting landholder observations, photographic images and published material about habitat recovery after fire.

Using a drone to gather images of fauna and flora

There is also collaboration with a WIRES-funded drone operation to produce images of post-fire flora and fauna within our patch of interest. This drone can capture high-resolution images through the use of an infra-red heat technique, even at night.

Forestry Corporation NSW and National Parks and Wildlife Service collaboration

Most of the Wamban-Nerrigundah patch falls within Forestry Corporation NSW and National Parks and Wildlife Service tenure, so a Forestry Corporation Specific Purpose Research Permit application has been granted and liaison is occurring with both agencies.

Existing Data on the Patch

Publicly available Forestry Corporation NSW Forest Type Maps and some history and condition data for thirteen Dampier State Forest compartments within the study patch have been cross-checked with the multiple vegetation associations listed for koala in the south-east corner on the NSW OEH Threatened Species site, and with nine SCIVI forest type classifications where past survey sites occurred near or within our patch of interest.

Cross-checking our own survey data

The Eurobodalla Koalas project itself previously produced data for 12 plot surveys within or adjacent to this Wamban-Nerrigundah patch, so these have also been cross-checked especially for the type, distribution and densities of browse species.

Surveys on private land

In 2020 we have already conducted plot surveys on private properties at Buckenbowra and Lilli Pilli (more are planned), checking not only for the properties’ own habitat suitability but for connectivity between themselves and neighbouring forested areas. The Buckenbowra site has excellent “koala trees” and connectivity with Mogo State Forest. Vegetation on the Lilli Pilli site is greatly valued by its owners but landscape-scale habitat suitability beyond the site suffers from substantial historical fragmentation caused by urban development without adequate biodiversity corridors.

In 2017 plot surveys were conducted for two private landholders interested in the capacity of their properties to offer browse for small numbers of koalas. One was a large property with eco-tourism and sanctuary potential and the other was a smaller property with a wildlife hospital. The data suggested the larger property could sustain a small number of captive koalas using its own eucalypts, whereas the wildlife hospital would need to import most browse from a separate property nearby for any recuperating wild koalas it might receive.

Our volunteers are available to conduct plot surveys for any interested private landholders.

Pilot Study

In 2013 the Eurobodalla Koalas Project published the final report of its scientific pilot study at this link Coastwatchers Koala Pilot Study Report

Components of the pilot study included a literature search, gathering of local knowledge through personal comments, a GIS (Geographic Information Systems) shire-wide potential habitat map-modelling exercise, and a series of ground-truthing plot surveys. The final document contains a comprehensive reference list, a report on the study’s peer review and a list acknowledging community members and agencies who helped.

Some minor items in the pilot study require correction or updating, but it remains a worthwhile document for those who want to delve into the theoretical basis, methodology, progress, outcomes and conclusions that form much of the basis for the project’s ongoing work.

Bendethera expedition

The pilot study was supplemented by a week-long expedition to Bendethera to conduct detailed habitat plot surveys, draw a conclusion about the location’s suitability as potential koala habitat and test a more complete set of habitat factors than those incorporated in the pilot study. The Bendethera Report can be accessed at this link: Bendethera Koala Habitat Survey Report

What next?

In 2021 the likely scientific focus will be koala sightings, habitat and cross-border connectivity in the north-eastern and south-eastern corners of the Eurobodalla Shire.

Koala sightings in December 2019 at East Lynne and in January 2020 in Bodalla State Forest (both after the fires) plus the emergence of new local knowledge suggest the project’s previous postulation that these are significant places for koala revival is ready for the next stage of validation.

The pilot study and subsequent enquiries point to the importance of connectivity for breeding between Bodalla and the Bermagui koala population, and East Lynne and known Shoalhaven populations.

There is also a need to better examine the viability of northern eucalyptus browse species such as Messmate (Eucalyptus obliqua), Sydney Peppermint (Eucalyptus piperita) and Grey Box (Eucalyptus moluccana).

Map of steepness overlaid on modelled potential habitat quality (South Eastern Eurobodalla)

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