2.2.1 Data Checking: Existing Data The majority of existing data has already undergone detailed and extensive checking during NEFBS and NRAC studies. A subset of the existing data, viz. most taxa assessed as Endangered or Vulnerable by expert review during the Interim Forest Assessment (IFA) has been assessed for spatial accuracy during the IFA process (Resource and Conservation Assessment Council. 1996b) (see Data Validation section 2.3 below).
Import runs of discrete data sets were manually scanned to check that field importation had proceeded correctly. Routine spot checks were made by checking known locality coordinates of some taxa with topographic maps or on GIS. This was performed by a field botanist with experience of the taxa and localities in question.
The CRA Access database contains reference libraries such as 'CAPS', the Census of Australian Plant Species (refer to Hnatiuk, 1990) and a NPWS mapping library containing details of 1:25000 and 1:100000 scale topographic map sheet names and their corner coordinates as well as spatially related information about public land tenure, reserves under the jurisdiction of various NSW government agencies, local government areas, and area names and their extent. Refer to NSW NPWS (1994) for further information. The CAPS library was used to check taxon names, and to update names in line with current taxonomic knowledge. The mapping library enabled an automated spatial check to be carried out on records at a map sheet scale. Anomalous records were quarantined from further use or, if possible, corrected.
2.2.2 Data Checking: New Data
All new data that were collected during this project and manually entered into the database were printed out and manually checked against the original pro-formas by two technical staff. Discrepancies were corrected immediately, or were sent to the relevant botanist to amend as appropriate.
The data validation process aimed to remove spurious or duplicate records and identify those plant records that were considered taxonomically correct and spatially accurate to within 100 metres of the stated locality. This was necessary to provide a set of records which could be used with confidence for species modelling and population viability analysis.
An automated procedure was utilised to firstly locate all records in the database that, for each taxon, were spatially identical. All but one of each of these records were quarantined. This was a random assignation process that did not necessarily select the primary record for each locality. This did not remove all genuine duplicate records, as coordinate conversion programs, used to convert latitude/longitude to a grid reference, have variable rounding-off criteria, which produces slightly different grid references from similar lat/longs.
The data accuracy notes made for records of priority plant taxa during the Interim Forest Assessment process were incorporated into the database at this stage. Proposed corrections from the IFA were implemented, and spurious records quarantined.
Two panels of expert botanists, one of rainforest experts R.J. Hunter (NPWS) and R. Kooyman (SFNSW) and one generalist panel made up of those botanists contracted for this project as well as D. Binns (SFNSW) and P. Richards (NPWS) were convened over a seven day period in April 1998. Using ArcView GIS, digital environmental layers and the CRA significant plants database, all records for a subset of taxa in the database were assessed for accuracy. Those records considered of insufficient accuracy were either corrected if possible or were quarantined from further use. Three quarantine fields in the database were used to indicate acceptable and unacceptable records and to document the validation process.
2.4 SELECTING TARGET TAXA
The Northern Flora Technical Working Group, convened by the Department of Urban Affairs and Planning and representing all relevant government agencies and stakeholder groups, developed explicit criteria which were utilised to determine priority species in the context of expert knowledge and available literature. The criteria included conservation status on State and Federal Acts, Rare or Threatened Australian Plant (ROTAP) status (Briggs and Leigh 1996), status applied to taxa during Interim Forest Assessment flora workshops (Resource and Conservation Assessment Council 1996b), regional significance, existing information on distribution, population attributes and threatening processes, amount of previous survey effort, ecology, and practicality of targeted surveys. The key criteria are summarised by the significance categories developed by the Forest Biota Response to Disturbance (RTD) project (Table 2.2; DeVries 1997; Richards et al. 1998). The FBRTD project was based upon JANIS criteria, and expanded upon previous key regional studies in rare plant classification systems (Keith 1990; Keith & Ashby 1992; Sheringham & Westaway 1997).
Table 2.2: Significance Category codes derived for the Forest Biota Response to Disturbance Project
Categories of Significance
Endangered taxa - a taxon in danger of extinction unless the circumstances and factors threatening its abundance, survival or evolutionary development cease to operate; priority is given to taxa which are endangered nationally as identified in the Commonwealth Endangered Species Protection Act 1992 and species listed under the NSW Threatened Species Conservation Act 1995.
Vulnerable taxa - a taxon likely to move into the endangered category within the next 25 years, unless the factors threatening its abundance, survival or evolutionary development cease to operate; priority is given to taxa which are listed as vulnerable nationally in the Commonwealth Endangered Species Protection Act 1992 and taxa listed under the NSW Threatened Species Conservation Act 1995.
Declining taxa - a taxon known to be adversely affected by prevailing land uses through either a significant decrease in abundance or a significant reduction in range at the regional level; the declining taxa category includes taxa not listed on either Commonwealth or State threatened plant lists but known or suspected to be declining at the national, state or regional level.
Rare taxa - taxon with small world populations that are not presently endangered or vulnerable but which may have a higher risk of extinction; such taxa may be identified with reference to the Briggs and Leigh (1996) or State rare plant lists or with reference to explicit criteria such as geographic range, habitat specificity, local population size, total number of populations, relative abundance or the frequency of records in collections.
Migratory and mobile taxa (nomads) – taxon in which populations, or components of populations, regularly or irregularly occupy different areas of the landscape because of changes in resource / habitat availability or due to the creation and maintenance of habitat (resource) patches.
Dependent on mature and over-mature forest - taxon dependent on forest in its mature and over-mature forest growth stages.
Taxa whose distributions do not correlate with any forest ecosystem.
Phylogenetically distinct taxa - taxon whose taxonomic position means that its potential loss will lead to a significant loss of biological diversity.
Taxa with complex spatial patterns of genetic variation.
Bioregional endemics - taxa in which 75% or more of the known range is contained in a single biogeographic region or which have a total range of 100,000 square kilometres or less.
Taxa with disjunct populations - taxon where populations have become physically separated over time due a break in a formerly continuous distribution or through long-distance dispersal over a barrier and as a consequence are morphologically or structurally distinct and have diverged genetically from parent stocks.
Taxa at the edge of their range.
Functionally important species - taxon whose disappearance from a system results, either directly or indirectly, in the loss of several other species, such as canopy species or species prominent in other layers.
Indicator taxa - taxon whose population response broadly reflects the response of a range of species populations to environmental changes resulting from particular land uses.
Economically or culturally important taxa - taxon of medicinal, agricultural or other economic value or species of scientific, social or cultural value.
Poorly known / recently described taxa - taxon yet to be described (undescribed taxa), species recently described (within the last 5 years) or recently segregated taxa (new species within an existing genus or new subspecies or varieties within an existing species).
Taxa presumed extinct - taxon presumed extinct at a State or National level.
Geographically Restricted - Taxa with an Australian geographic range of <100 km.