Eco Logical Australia was commissioned by the National Park and Wildlife Service (NPWS) to undertake vegetation survey and mapping of Coolah Tops National Park in 2019. The reserve includes the former Bundella and Warung State Forests and was gazetted as National Park in 1996. The reserve forms part of the Liverpool Range which makes up the largest lava field province in NSW, dated between 32 and 40 million years covering an area of over 6,000km2 with up to 400m thickness of basalt.
The project sought to review existing data and mapping and align vegetation communities with the current state-wide Plant Community Type classification through the collection of strategic data on floristic and structural diversity. Existing vegetation surveys and mapping were reviewed and supplemented with over 340 rapid data points. Plant Community Type mapping was undertaken at a scale of between 1:2,500 and 1:10,000 using a range of datasets. Development of linework and attribution of Plant Community Types was undertaken in three dimensions using high resolution stereo ADS40 imagery. The final mapped product is considered accurate at a 1:5,000 scale.
A total of 464 species from 82 plant families were recorded, of which 13% were exotic (four being priority weeds). A total of 24 unique Plant Community Types (totalling 16,264 hectares) were mapped. In addition, more than 160 separate subtypes were mapped due to significant variability with each Plant Community Type based on the dominant species in each patch. The vast majority of vegetation mapped falls within the Grassy Woodlands Formation, followed by Dry and Wet Sclerophyll Forests respectively.
A range of management considerations are discussed including: management of old growth forests dominated by Eucalyptus pauciflora (Snow Gum), E. nobilis (Mountain Ribbon Gum) and E. laevopinea (Silvertop Stringybark); inappropriate fire regimes; biosecurity including feral animal and weed management; and track maintenance.
Based on the results of this project, the following recommendations have been developed:
• Conduct detailed research into the likely fire ecology of each PCT including recent and likely historic fire regimes as well as sensitive species to better inform fire management requirements.
• Review and update relevant fire management plans taking into consideration the minimum fire intervals, mosaic burning practises, the adequacy of existing trail networks, management of fire in long unburnt forests and consideration of impacts to conservation significant species.
• Establish a biodiversity monitoring program to determine changes and help manage the effects of climate change over time. As an isolated basalt plateau, many of the species and communities that occur in the reserve are restricted and are unlikely to be able to adapt in a changing climate.
• Control priority and environmental weeds. Early detection and eradication of any Scotch Broom or Gorse is recommended.
• Control feral animals including goats, pigs and deer.
• Should additional funding become available, additional targeted vegetation survey across a range of PCTs, particularly in the south east where access is limited, would help to further define and understand the floristic and structural diversity of the reserve.
• Spring surveys for rare and threatened species including orchids are recommended in wetland areas, high altitude forests and in steep gullies and rock outcrops.
• Investigate the significance of rare and regionally significant PCTs with the intent of nominating communities for listing under the BC Act and/or EPBC Act. Specifically, a review of PCT 497 Teatree shrubland / sedgeland / forbland swamp wetland should be undertaken for consideration of amendment to the listing of the BC Act Endangered Ecological Community Upland Wetlands of the Drainage Divide of the New England Tableland Bioregion.
It is understood that EES is currently undertaking a review of the state-wide PCT classification including a complete reanalysis with the intent of refining each PCT and developing positive diagnostic species. This review may help to redefine some of the PCTs mapped as part of this project, and some new PCTs may be created and old PCTs retired. A review of the mapping undertaken as part of this project is
recommended once the review has been completed.