Cell Descriptions - South East Natural Resources Management Board

SE7 – Canunda NP
nationally vulnerable Dwarf Galaxias. In conjunction with the nearby Mullins Swamp, Lake
Frome has been considered as the most important wetland in the South East outside of Bool
Lagoon (SEWC, 1984). However, the system does show signs of declining health, coupled with a
trend toward habitat homogenisation via the spread of Typha domingensis. In response to these
trends, hydrological restoration has been identified as a key objective in the Lake Frome CP
Management Plan (DEH, 2003). Farrington (2009) investigated the wetland restoration feasibility
in terms of depths and volumes of inundation, potential ecological impacts and flood
management implications. A hydrological model has since been developed for the drainage
catchments (Geoff Woods, DENR pers. comm. 2010) and monitoring infrastructure has been
installed in order to more accurately assess drainage inflows and volume retention. Based on a
ground-truthed digital elevation model, water could be retained to a depth of 1.5m AHD via an
outlet regulator, without the need for levee banks. It would be possible to hold water up to 2.2m
AHD without significant flooding back up any of the inflow drains, however large earthworks
would be required for levee banks to protect surrounding, low-lying properties. Based on
preliminary hydrological data, the volume of water required to fill the wetland basin up to a
volume of 2.2m AHD has been delivered in eight out of the last ten years (Farrington, 2009) and
so security of necessary inflows remains high despite an unprecedented period of low rainfall.
Ongoing collection of groundwater and surface water data, including inflow volumes and salinity,
form an extension of background investigations. In addition, the regular monitoring of vegetation
is a priority site action for DENR. The greatest obstacle to hydrological restoration is opposition
voiced by neighbouring property owners. A key recommendation for the restoration of Lake
Frome is engagement of the local community and an evaluation of any concerns using data and
information that has been and continues to be collected.
Conservation Analysis (GIS)
The summary of cell conservation means shows that this cell is the third highest conservation
priority in the region (136.3). The bulk of the medium to medium high values are in the older
inner vegetated dune areas (see conservation summary map below); the whole of Lake Frome
Conservation Park exhibits very high values; a smaller area, from Cullen Bay to the Cape Buffon
shows high totals within 150m of the vegetated cliff line. In contrast, the de-vegetated dunes on
the slopes leading to the shoreline show low to medium low values.
Lake Frome CP records very high scores for threatened reptile habitat, butterfly habitat and
habitat for 6 out of the 7 focal species – Orange Bellied Parrot, Fairy Tern, Swamp Antechinus
(last viable population in SA; nb likes vegetation with a dense under storey, it is a late invader and
hence is threatened by fire), Swamp Skink, Yellow Sedge Skipper and Southern Bell Frog.
The cell has high values for state rarity of vegetation communities; priority for the threatened
status of flora is high throughout the vegetated dune areas; also the dunes accumulate the highest
values for plant associations only found in this region within the state floristic survey. However,
numbers of threatened species, and total numbers of species are not high, both in the wetland
and the dunes. Significant habitat for butterfly species is recorded throughout the vegetated
dunes and the Lake Frome swamp. Vegetation block metrics – size, shape and connectivity – all
score highly. The entire foreshore,