A recent visit to Ballina on the north coast of NSW provided an opportunity to visit a 130 hectare area of new Koala habitat west of Wardell that Corkery Consulting was involved in. The project formed part of the Pacific Highway upgrade and provided a rare opportunity to contribute to the creation new habitat to support one of Australia’s iconic wildlife species, which is under increasing threat of extinction. It was particularly gratifying to see stands healthy trees beginning to provide new habitat for local Koala communities and a corridor connection between significant areas known habitat.
Construction of the 120 km section of the Pacific Highway between Woolgoolga to Ballina by Pacific Complete formed the final link in the Pacific Highway upgrade project between Hexham near Newcastle and the Queensland Border. We were engaged by Pacific Complete (PC) to prepare landscape design documentation for implementing the new habitat planting. Dr Rod Kavanagh who is a recognised expert on Koalas provided advice on revegetation issues including tree species selection, tree spacing, planting layout and bushfire management issues.
Establishing the 130 hectares of new Koala habit tree planting as an offset to the vegetation cleared for the road works achieved a significant ecological outcome of the project. The new Koala habitat straddles the highway to connect existing core Koala habitat areas located to both the east and west of the highway corridor. A series of wildlife underpasses were constructed as part of the highway works to allow Koalas to move safety between the habitat areas.
Potential planting areas were identified and mapped, taking account of existing infrastructure, vegetation and growing conditions. A priority schedule for the tree planting program was developed that was based on site inspections to assess the proposed planting areas. Growing conditions are highly variable and included extensive low elevation areas previously cultivated for sugar cane that have poor drainage and a high water table, lower slopes of hills to the west and sand dune areas to the east of the highway corridor. The Tender documents therefore specified that soil testing be carried out by a registered laboratory and implementation of soil amelioration recommendations. Detailed planting plans, schedules, plant quantities, specifications and a preliminary planting strategy were prepared by Corkery Consulting and used in the tendering process. Local plant nurseries were contracted to confirm plant availability and supply arrangements for the tree species identified as Koala habitat species
In summary the Koala Habitat project covered;
Species Selection – species selection based on soil mapping and location on slope and connectivity to established areas to develop priority
Site preparation – weed control pre planting, mechanical ripping, treatment for specific slopes
Planting rate and size – spacing , pot size, timing, lead time for propagation, planting method, ordering provenance seed
Maintenance – fencing for protection, watering, weed suppression, on-going erosion protection
Monitoring annual sampling over 5 years - opportunistic observations, annual report summary, monitor recommended number of koala SAT plots, Management review and response.
Planting commenced in 2016 and initially the tree growth was constrained by competition from heavy weed cover. However, the growth rate accelerated over the last few years as the tree canopies begin to shade out the grasses. The recent site visit confirmed that a substantial new area of Koala habitat has be created that is beginning to make a significant contribution to sustainability of a local Koala community.
