The Biodiversity Corridor Mapping project is progressing well.  So far, six of the TML work sites have been mapped, namely, Plunkett Creek, Tamborine Mountain State High School, Holt Park, Rosser Park, Contour Road and Ohia Court. Typical features that have been mapped include creeks, drainage lines, the perimeters of large weed infestations, the perimeters of planted areas, point locations of significant trees (mature native trees or large weed trees marked for removal) and any other physical features which may impact on management decisions. An intensive mapping schedule is lined up for the forth coming month with a visit planned to each of the TML work sites before the end of June. With his intimate knowledge of the sites and the vegetation, John Bestevaar is accompanying me in the capacity of nature advisor.

To date the mapping has been carried out using a handheld GPS-based mapping unit, which has been generously loaned to TML by the Brisbane City Council, a significant in-kind contribution to the project. A more recent in-kind contribution to the project is the supply of Rinex data free-of-charge from the Department of Natural Resources and Water’s SunPOZ services.  For those who are unfamiliar with this, Rinex data is additional GPS data collected from dedicated ground receiving stations and is required for post-processing GPS readings in order to improve their spatial accuracy by up to 5m or more. Given that these data normally cost $40 per hour of mapping time and so far in excess of 34 hours of mapping has been carried out with an estimated 50 hours of mapping still ahead of us, based on these estimates this tallies up to $3 560 (for this project alone), which is significant indeed! So good on you, DNRW!

Looking to the future beyond the current project, the feasibility of purchasing a high precision GPS-based mapping unit for TML has been investigated.  Dorean Erhart (management committee member) and I met with a representative from Trimble last Friday (16 May) to test drive a couple of their units. The upshot of this is that Trimble have offered us a unit capable of 1-3m accuracy (post-processed), valued at $8 000, for almost half the cost. Not wanting to look a gift horse in the mouth, plans are afoot to apply to the Gambling Benefit Fund for the required funding. Once the cost of the software and peripheral hardware (i.e. cables, etc) are included, the grand total tips $12 000.

While one of the primary objectives of the Biodiversity Corridor Mapping project is to map the creeks on the mountain to improve the delineation and definition of the biodiversity corridor network, there will be incidental spin-offs which will impact directly on site coordinators, including detailed maps of every TML work site. It is anticipated that these maps and the underlying spatial data layers in the GIS database will provide invaluable logistical support through (amongst other things) their ability to quantitatively calculate area and length of features with ease (and hence help in estimating the size of task-forces required to clear a certain area; or the number of specific plant types required to revegetate areas in specific locations), as well as its ability to provide insight into the spatial relationships between features on the sites.

Rebecca Castley - Member and digital mapping project manager.