Beautiful Valley Creek, near Horrocks Pass
2012 Aquatic Ecosystem Condition Report
- Dry in autumn and spring 2012
- Likely to be enriched with nutrients when wet because a large part of the catchment is grazed by stock
- No evidence of any bank erosion or stock accessing the creekbed at the site sampled
- Riparian vegetation consisted of native gums and shrubs over a weedy understorey
About the location
Beautiful Valley Creek is a small intermittent stream in the Southern Flinders Ranges that rises about 2 km north-east from Mt Remarkable National Park and 1 km north from Hancock’s Lookout, flows north-east and during exceptionally wet years eventually discharges into Willochra Creek. The major land use in the 2,957 hectare catchment, upstream from the site sampled, is grazing modified pastures (78%), with smaller areas used for native vegetation (18%), roads (3%) and cereals (1%). The monitoring site was located at a ford on Gunyah Road, about 2 km north-north-east from Wilmington.
The creek was given a Fair rating because the site sampled showed evidence of moderate changes in ecosystem structure, and some changes to the way the ecosystem functions. There was evidence of human disturbance due to the extent of weed growth in the understorey vegetation but the stream provided a range of fine and coarse sediment types and was dominated by native trees and shrubs.
The sediments were dominated by detritus, boulder, cobble and gravel, with smaller amounts of pebble, sand, silt and clay also present. Samples taken from below the surface were grey sands, and showed no signs that the sediments were recently anaerobic, or lacking in oxygen. No signs of any bank erosion or stock accessing and defaecating at the site were recorded in 2012.
Two types of emergent aquatic plants (sedge Cyperus gymnocaulos and rush Juncus) were recorded in patches at the site and there was no evidence of any dried algal deposits from the channel. The riparian vegetation was dominated by River Red Gums over weeds, introduced grasses, sedges and rushes. The surrounding vegetation at the site included scattered White Cypress Pines, gums, and acacias over introduced grasses and hay paddocks.
Special environmental values
Beautiful Valley Creek is an ephemeral stream in the Southern Flinders Ranges with a catchment that includes areas of grazed lands and native vegetation. No significant environmental values were recorded from the dry site in 2012. However, previous sampling of the same site in 1998 recorded a range of aquatic species from the pools that were present during a much wetter period. They included several regionally rare species of molluscs (e.g. Gyraulus, Isidorella and Ferrissia) that generally occur from permanently wet streams as well as a range of tolerant generalist species of beetles, flies, waterbugs and caddisflies.
Pressures and management responses
|Livestock and feral animals have direct access at the site and upstream, exerting excessive grazing pressure, causing sediment erosion and adding excessive nutrients to the watercourse||
The Northern and Yorke Regional NRM Plan has the following Resource Condition Targets:
Natural Resources (Northern and Yorke) has also been updating its understanding and management of the Willochra Catchment: