OPR Rail Proposal – Vegetation and Flora Assessment
to 284 km)
to 400 km)
to 560 km)
at 330 km)
68 (outlier to
to 475 km)
P1 = Priority 1, P2 = Priority 2, P3 = Priority 3, P4 = Priority 4, Vul = Vulnerable, DRF = Declared Rare Flora
National significance refers to those features of the environment which are recognised under
legislation as being of importance to the Australian community; in particular, species listed under the
EPBC Act are regarded as nationally significant. State significance refers to those features of the
environment that are recognised under State legislation as being of importance to the Western
Australian community, in particular, species listed as DRF under the WC Act are of state significance.
During the current survey, two flora species of national and state significance were recorded in the
Study Area: Caladenia hoffmanii (Endangered, DRF) and Eucalyptus blaxellii (Vulnerable, Priority 4).
During the database searches, an additional two flora species of national and state significance were
recorded in the Study Area; Drummondita ericoides (Endangered, DRF) and Philotheca wonganensis
(Endangered, DRF). The significance of these species is discussed below.
endemic to the Geraldton Sandplains bioregion as shown by the current WA HERB distribution for
Using the information provided in Table 8.2, this species is known from 285 individuals at 38
locations. Of these 93% of the total number of plants were inside the Study Area.
Caladenia hoffmanii grows in clay or sandy‐clay on laterite rocky hill sides and ridges, or in winter
wet flats. A disjunct occurrence is recorded 600 km south‐east of the Geraldton area in the Pinharing
area, growing around large granite outcrops. These habitats are not widespread in the Study Area
and the region and the large percentage of total individuals (52.3%) recorded in the Study Area
indicates a high local endemism for this species.
The known populations of C. hoffmanii are severely fragmented and the quality of habitat for many
populations is in decline (Pers. com. Murray Baker, DEC, 2009). The EPBC Act conservation advice
lists the main threats to C. hoffmanii as fire and grazing by feral pigs and rabbits.
Due to the fragmentation of the populations, decrease in habitat quality, the small distribution of
known occurrences (50 km with one outlier to 70 km), the high percentage of the total population in
the Study Area and the likelihood that it is locally endemic to the area, it is considered that C.
hoffmanii has high local significance in the Study Area.
been recorded in the Geraldton Sandplains and Avon Wheatbelt bioregions as shown by the current
WA HERB distribution of E. blaxellii in Figure 8.2 below.
Using the information provided in Table 8.2, this species is known from 2,948 individuals at 170
locations. Of these 24% of the total number of plants were recorded inside the Study Area.
The EPBC Act conservation advice states the main threat to E. blaxellii is inappropriate fire regimes,
however most known populations are secure as they occur in areas that are unsuitable for farming
due to the inaccessibility of the steep slope.
is widespread at the Western end of the Study Area. As these habitats are moderately widespread in
the region and as the percentage of total individuals is moderate (16.4%) in the Study Area, it
indicates a low to moderate local endemism for this species. E. blaxellii does not appear to be locally
restricted with records spaning 70 km and one outlier to 170 km.
Eucalyptus blaxellii has recently been removed from the WC Act DRF list, but still remains on the
EPBC Act listing as vulnerable. Because of the large population numbers, longevity, disturbance
recovery abilities and the removal of E. blaxellii from the listing of DRF (WC Act) it is considered that
is endemic to the Geraldton Sandplains bioregion as shown by the current WA HERB distribution of
Using the information provided in Table 8.2, this species is known from 212 individuals at 12
locations. Of these 5% of the total numbers of plants were recorded inside the Study Area.
The DEC’s Moresby Range Drummondita Interim Recovery Plan (DEC, 2004) for D. ericoides states
that the main threats include inappropriate fire regimes and high levels of human activity.
Drummondita ericoides grows on low heath on sandstone and laterite slopes, ridges and gullies of
the Moresby Range in brown loam or sandy loam and clay soils in areas not suitable for agriculture
and so has not been so highly cleared.
Drummondita ericoides appears to be locally restricted with all known records spaning 40 km and
therefore has high local significance in the Study Area.
has been recorded in the Geraldton Sandplains and Avon Wheatbelt bioregions as shown by the
current WA HERB distribution of P. wonganensis in Figure 8.4 below
Distribution of Philotheca wonganensis
Using the information provided in Table 8.2, this species is known from 136 individuals at eight
locations. Of these 8% of the total number of individuals were recorded inside the Study Area.
Philotheca wonganensis grows in red sandy soils over fractured greenstone. These habitats are not
very widespread in the region, and the percentage of total individuals (8.1%) recorded in the Study
Area indicates a high local endemism for this species. P. wonganensis appears to be locally restricted
with most of the known records spanning 30 km, with one outlier to 300 km.
Because of the low known population numbers and as 8% of the total known individuals were
recorded in the Study Area, impact to the species could result in a significant loss and despite the
large percentage (12.6%) of individuals in conservation reserves P. wonganensis has high local
conservation significance in the Study Area.
Regional significance addresses the representation of habitats at a biogeographic regional level.
Priority Flora taxa that are endemic to the Geraldton Sandplains, Yalgoo and Murchison bioregions
and whose distributions are limited or unknown are considered regionally significant.
Fifty‐five Priority Flora taxa were recorded during the current survey of the Study Area and an
additional 32 were recorded by the DEC searches or other sources as listed in Section 8.
Species that are endemic (using information provided from the WA Herb) to one IBRA bioregion
include the following;