Figure 1. Example of NaturePrint with BioSites in the north-west of Melbourne.
NaturePrint shows this area of the outskirts of Melbourne as having some of the highest biodiversity values in Victoria, yet this area has had a long history of agriculture and intensive land use and in reality, the significant areas are restricted.
Victorian government planning once relied on use of individually mapped and documented BioSites. Now a simplified state-wide map and computer modelling inform decisions. Nic McCaffrey and Graeme Lorimer explain what has been lost and gained.
‘Sites of biological significance’ are defined areas of land or water containing high biological values such as threatened species or ecological communities (DSE 2005). Most of the recognised sites have been mapped, documented and rated in the course of systematic studies of individual regions. Some other sites gain recognition through ecological studies of individual sites, because the regional studies are rarely exhaustive. Each site is given a significance rating, for which objective criteria were devised by (Amos 2004). Beginning with the Port Phillip region in 2003, predecessors of the Victorian Department of Environment, Land, Water and Planning (DELWP) published maps and data for these sites, which they dubbed ‘BioSites’. The mapping, data and significance ratings helped to inform protective measures, management activities and prioritisation of our most precious natural assets.
For example, BioSites are usually given specific protection in planning schemes (Victorian Government 2002), and public land managers often know that management activities within mapped BioSites need to pay special attention to what has been documented about the sites. (DNRE 2002) regarded the BioSites information as ‘an essential foundation for planning and land management decisions’. During 2003–2013, the Victorian government’s ‘Native Vegetation Framework’ required consideration of a BioSite’s significance rating whenever a permit was considered for removal of native vegetation within the site.
But in recent years, DELWP has abandoned the BioSites concept and withdrawn online access to the BioSites mapping and information. Instead of the BioSites mapping and data, DELWP have replaced significance with a state-wide map called ‘NaturePrint – Strategic Natural Values’. DELWP also intends to revamp the online database called ‘Actions for Biodiversity Conservation’ (ABC) to catalogue each site’s natural assets. The change from BioSites represents a move toward a state-wide standardised approach to managing biodiversity that relies more on computer modelling than expert interpretation of each site and its regional context.
What have we gained and lost from this change?
BioSites’ history, strengths and weaknesses
As far as we know, the first Victorian study designed to map, document and rate a set of BioSites was that of (Gullan et al. 1979) for the Upper Yarra Valley and Dandenong Ranges. There have been many subsequent studies of regions or individual BioSites by government, private consultants and naturalists in various parts of Victoria (e.g. those listed by (DNRE 2002)). They have involved field surveys, literature search, ecological analysis and sometimes strategic planning analysis.
At their best, the BioSites studies have delivered consistent, objective assessment of the relative merits and needs of all (or nearly all) BioSites within a municipality or region. Such a survey allows determination of the interrelationships between BioSites, e.g. how a rare bird species moves between different sites to meet its varying seasonal needs. The boundaries of the sites are typically chosen to align with boundaries that relate to management or zoning of the land, thereby simplifying the translation of ecological information into land management and planning. Consistency across the region or municipality simplifies strategic planning and aids allocation of resources and protective measures between the sites.
However, the thoroughness, consistency and level of detail of BioSites assessments has varied greatly across Victoria. In part, that is inevitable: a peri-urban region with limited natural areas and a high population can sometimes afford a thorough, detailed study, unlike a rural region containing large tracts of pristine forests and sparse population (Lorimer 2005). Regional or municipal BioSites studies differ in age and often the approach taken by the investigators. In some studies, the site boundaries tightly circumscribe the areas of significance, while in other studies, the sites include substantial buffer areas and a matrix of significant and non-significant land. BioSites studies are therefore difficult to compare and they make imperfect guides for prioritising state or federal resources and protective measures between regions or municipalities.
The age of computer modelling
As described in the article on page 8, NaturePrint represents a state-wide map of the perceived importance of flora and fauna, with a resolution of 75 m. Because detailed field data and expert knowledge about flora and fauna vary greatly across Victoria, NaturePrint instead uses a greatly simplified representation of flora and fauna and it extrapolates that representation to locations where data is deficient. In essence, the price for overcoming the patchy, inconsistent information about BioSites has been the inability to take into account a lot of detail and expert interpretation.
This conclusion is supported by a recent study that sought to use NaturePrint to guide the application of the Environmental Significance Overlay in the Shire of Yarra Ranges (Ecology Australia 2013). That study found that it was necessary to augment NaturePrint mapping with additional data including aerial photo interpretation, previous BioSites studies and field validation.
Despite the need for tweaking experienced in the Yarra Ranges, NaturePrint probably works well in reasonably large, forested landscapes as the vegetation mapping is more reliable and datasets more accurate. In heavily cleared grassy and grassy woodland landscapes, NaturePrint appears to be less reliable and more liable to overestimate or underestimate biodiversity values, threatening processes and ecosystem function.
If we look at an example in the north-west of Melbourne (Figure 1 on page 4), we see that NaturePrint, compared with BioSites probably overestimates the biodiversity importance. Even parts of the Calder Park raceway (an extremely unnatural environment) get some of the highest values possible in the State! Also, it is not clear in this example, and many others like it, where the valuable small and narrow BioSites are. For example, the two National BioSites near Holden Road BioSite #3568 and BioSite #3569 were (and hopefully still are) known sites for the Spiny Rice-flower Pimelea spinescens subsp. spinescens and Large-fruit Groundsel Senecio macrocarpus. Both those species are listed as threatened under the federal
Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act). These sites are not apparent from the surrounding landscape and cannot be expected to be picked up by NaturePrint.
In the past, many rail and road operators understood the need to avoid impacts within BioSites such as for routine vegetation maintenance and sight clearance. Also, how many developments, major infrastructure projects and land management decisions factored in BioSites for a better balance between development and conservation? Previously for site based decisions, anyone could look up Biodiversity Information Maps and see at least this is an important area and get an idea of why the site was listed and what type of management and monitoring has been undertaken.
The Actions for Biodiversity Conservation (ABC) database
The ABC is an internet-based database used by DELWP to store data about the management of threatened species and communities across Victoria. See link Home>Environment and wildlife>Conserving threatened species and communities>Actions for Biodiversity Conservation. Its operation commenced in 2004 for three main purposes:
- To describe important threatened species populations or communities and track their management actions via population monitoring and other programs;
- Generate information for Action Statements under the Flora and Fauna Guarantee Act (FFG Act); and
- Modelling to determine the relationship between management actions, threats and variables which influence the status of populations and assess the cost-benefit of various management options.
In its current form, the database is restricted to government staff and other registered users and there is no apparent spatial dataset available for wider usage. According to DELWP, the ABC is set to be revamped and will essentially replace the register of site-based management actions which BioSites previously helped with. Also, the extent of management will be viewable via polygons on a map and will be quite specific on detail for management of threatened flora and fauna. The dataset will also be made available via a new version of Biodiversity Interactive Maps called the Biodiversity Information Portal.
This all sounds positive but we hope that in the upcoming changes to the ABC database, along with the review of native vegetation regulations and the FFG Act, important/significant sites aren’t lost in the zeitgeist of modelled datasets, now used more and more for environmental decision-making and prioritising biodiversity conservation.
Specifically, we would like to see clear spatial identification of important sites for threatened species and their habitats, as well as regionally threatened species and communities (not just state or federal threatened species) as an item on the soon-to-be released Biodiversity Information Portal or through the ABC database. These ‘important sites’ identified by a combination of high-value NaturePrint sites, previous BioSites studies and site-validated and peer-reviewed data. Also, if we are to take these important sites seriously, there would be additional permit requirements under planning schemes as well as the FFG Act.
A comment was sought in vain from DELWP.
Amos, N (2004), The standard criteria for defining sites of biological significance in Victoria, Department of Sustainability and Environment, Melbourne.
DNRE (2002), BioSites: Sites of Biodiversity Significance in Port Phillip and Westernport Region Victoria, Department of Natural Resources and Environment, Melbourne.
DSE (2005), Biosites and Mapping Updates – Port Phillip Region, Department of Sustainability and Environment, Melbourne.
Ecology Australia (2013), Yarra Ranges Environmental Significance Overlay Review (Stage 1), Authors L. Crowfoot and A. McMahon. Prepared by Ecology Australia for Shire of Yarra Ranges.
Gullan, PK, Parks, D, Morton, A & Bartley, M (1979), Sites of botanical significance in the Upper Yarra Region, Minister of Conservation Victoria, Environmental Studies Program, Upper Yarra Valley and Dandenong Ranges Authority.
Lorimer, GS (2005), ‘Municipal-scale conservation of plant species around Melbourne’, Australian Plant Conservation, vol. 14(2):18-19.
Victorian Government (2002), VPP Practice Note – ‘Biodiversity’.