Tributary of Unnamed Creek, Sellicks Beach, SE from Sellicks Hill
2013 Aquatic Ecosystem Condition Report
- Dry in autumn and spring 2013
- Likely to be enriched with nutrients when wet due to the surrounding land uses in the catchment
- Riparian vegetation lacked native species and comprised woody weeds over introduced grasses and weeds
- Some areas of bank erosion caused by past flood and stock damage of the banks were evident
About the location
This Unnamed Creek near Sellicks Hill is a very small stream that rises off the north-west side of the Sellicks Hill Range at an elevation of about 345 m. It flows for a couple of kilometres and joins with several other unnamed streams to form a channelised creekline, which discharges into Gulf St Vincent at Sellicks Beach after exceptionally heavy periods of rain on the surrounding hills. The major land use in the 141 hectare catchment was stock grazing (sheep and goats), with minor areas also used for roads and mining. The site was located off Old Sellicks Hill, about 1 km south-east from the township of Sellicks Hill in the Southern Mount Lofty Ranges.
The creek was given a Poor rating because the site sampled showed evidence of major changes in ecosystem structure and function. There was evidence of human disturbance due to the lack of native plants associated with the creek, in a catchment where most of the native vegetation has been cleared and used for cropping and grazing since in the early days of European settlement.
The3- 5 m wide channel was dry in both autumn and spring 2013. No macroinvertebrate or water quality data was consequently available for this site.
The sediments were dominated by detritus and clay, with smaller amounts of sand, gravel, cobble and boulder also present; samples taken from below the surface were red sands and there was no evidence to indicate that the sediments had recently been anaerobic or lacking in oxygen (e.g. no odours or signs of blackened sediments). There was a small amount of bank erosion present which appeared to have been caused by past flood and stock damage of the steep, poorly vegetated banks.
There was no evidence of any dried filamentous algal mats or aquatic plants within the creekbed, which indicate that the creek remains dry for most of the year. The riparian zone lacked any native plants and comprised a few scattered olive trees over introduced grasses, weeds and bare soil. The surrounding vegetation near the creek comprised a few scattered gums over introduced grasses among cleared sheep grazing paddocks.
Special environmental features
Pressures and management responses
|Widespread introduced weeds in the riparian zone at the site and upstream (reducing habitat quality).||The Adelaide and Mount Lofty Ranges NRM Board has several pest plant (weed) mitigation and control programs. They work closely with landholders to control weeds on their property and to help stop the spread to other properties and waterways.|
This aquatic ecosystem condition report is based on monitoring data collected by the EPA. It was prepared with and co-funded by the Adelaide and Mount Lofty Ranges NRM Board.