Appendix D Terrestrial and Aquatic Biodiversity - Environment ...

feature the three species of freshwater sawfish and possibly Gulf Snapping Turtle, all of which are listed as
threatened. Moreover, riparian habitat provides refugia during fires and offers potential habitat for threatened
and restricted species.
The presence of riparian vegetation is geographically restricted to the edge of waterways. Riparian
vegetation assessment sites were surveyed at seven proposed haul road crossing sites located at six major
water courses along the route. Given the broad width of the Limmen Bight River, both banks were assessed.
Only one bank was assessed at the Cox and Nathan Rivers and the Rosie, Pine and Bing Bong Creeks.
Assessment of riparian habitats at proposed crossing points shows that in general riparian vegetation strips
surrounding watercourses along the haul road are narrow and subject to seasonal flood events, resulting in
high impact on species present.
No flora species of conservation significance were located during the survey, however one grass species
Enteropogon minutus listed as data deficient was recorded on both banks of the Limmen Bight River. All of
the seven survey sites were located in the McArthur Land System described as “Mid-high open woodland of
Corymbia terminalis and Eucalyptus microtheca with some C. bella and C. polycarpa. Tall fringing riparian
vegetation often includes Melaleuca spp.” (Aldrick and Wilson 1990). Survey sites were typically dominated
by riparian species in the upper stratum including Melaleuca ssp., Casuarina cunninghamiana, Eucalyptus
camaldulensis and Lophostemon grandiflorus. This differed at the proposed crossing at Bing Bong Creek
where Callitris intratropica was recorded as dominant in the upper stratum. This species was frequently
observed in the landscape around Bing Bong Creek within the Fletcher Land System.
Weeds were opportunistically surveyed at each of the proposed crossing sites. Bellyache Bush Jatropha
gossypiifolia (Class A under the Weeds Management Act 2001) was identified near the riparian assessment
site. Management of this Class A riparian weed must eradicate and prevent the spread of the species as it
can highly impact native riparian vegetation. Given its difficulty to manage, preventing further spread is a
high management priority for this species. Other classified weed species surveyed adjacent to riparian
vegetation included Hyptis suaveolens and Sida acuta (Class B under the Weeds Management Act 2001) at
3 of the 7 sites surveyed.
In constructing the haul road bridges or culverts will be constructed, depending on the width, depth and flow
of the watercourse to be crossed. It is recommended that culverts be put in place during construction of the
haul road to minimise the disruption of surface water flows.
Vegetation descriptions and photo plates for each riparian assessment site are provided in Appendix D-10.
Client: Western Desert Resources Ltd Page 114 of 150
Doc No. DW120004-C0302-EIA-R-0036
Doc Title: Appendix D – Terrestrial Biodiversity Technical Report