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Ballina Koala Habitat Study
Executive Summary The Ballina Shire Council Local Government Area (LGA) encompasses an area of approximately 49,200ha located between Wardell and Lennox Head on the far-north coast of NSW. This report describes the results of the first shire-wide assessment of koala distribution and abundance for the Ballina LGA.
Analysis of 515 historical koala records for the Ballina LGA confirms that koalas have a history of occupation in the study area that extends back more than a century. Over the last 3 koala generations (1995-2012) and in common with the adjoining Lismore LGA, the records imply an increase in the key range parameter Extent of Occurrence from more southern areas of the LGA into farmland on the Alstonville Plateau. For the same time period the records further suggest a significant increase in the associated range parameter Area of Occupancy from approximately 46% of available habitat for the time period 1949-1994, to nearly 60% of available habitat. Based on data for the last 6 koala generations covering the time period 1974-2012, historical records for the LGA further indicate the presence of a major source population in the southern section of the study area coinciding with the localities of Bagotville, Meerschaum Vale, Coolgardie and Wardell, with northern outliers in the Uralba and Lynwood areas. Reasons for increases in both the Extent of Occurrence and the Area of Occupancy are considered to be associated with farming activities on the high nutrient soils formerly occupied by the Big Scrub rainforest, specifically the use of Eucalypts such as Tallowwood for windbreak purposes which has consequently created a habitat matrix now capable of sustaining resident koala populations.
Because of its location, relatively small size and high nutrient soils in more elevated areas, vegetation cover across most of the Ballina LGA is extensively fragmented with high levels of invasion by species such as Camphor Laurel on more fertile soils. Subject to landholder permissions, koala habitat assessments to obtain koala food tree preference, population and occupancy data used a systematic sampling strategy employing the Spot Assessment Technique (SAT) methodology at 1,000m and 500m (supplementary) intervals. Collectively, 123 primary field sites were initially identified for sampling, 56 of which were formally assessed, while a further 19 supplementary field sites were located around primary field sites wherein koala activity had been recorded. Evidence of habitat use by koalas, specifically the presence of koala faecal pellets, was recorded in 18 of the 56 primary field sites which provided a contemporaneous Area of Occupancy estimate for the LGA of approximately 32% of available habitat. Significantly, over 70% (13/18) of active primary field sites were located in the aforementioned area between Bagotville, Meerschaum Vale, 5
