Alarm over Ewens' decline
Gerard Carmody
 

Eight Mile Creek is a natural watercourse running from Ewen’s Ponds to the sea.

Ewens Ponds and Eight Mile Creek, one of Australia’s natural wonders, may not be here for us to enjoy in the years to come. The rapid decline of the series of ponds, one of Australia’s best and iconic freshwater dive sites located in the South East of South Australia, is alarming conservationists, divers and the community.

 Ewens pygmy perch (Nannoperca variegata) and the Glenelg Spiny Crayfish (Euastacus bispinosus) are angered and under threat in Ewens Pond. Photographs: Rudie Kuiter.

Ewens Ponds are set to be one of many environmental casualties caused by global warming and our current drought. With rainfall in the past ten years at its lowest on record in the water catchments feeding Ewens Ponds, an outbreak of blue-green algae has occurred causing a massive dieback of aquatic plants. These plants are essential to ecological balance of the ponds and their reduction has caused a significant decrease in populations of slower moving aquatic fish and invertebrate species. The water problem for Ewens Ponds is magnified by relevant management authorities continuing to allocate too much water to local irrigators trying to drought-proof their farms and timber plantations. Ewens, a freshwater ground-dependent ecosystem, is suffering as a result of this miscalculation of water allocation and the failure to address the problem.

This map from 1896 shows Eight Mile Creek as a natural watercourse running from Ewen’s Ponds to the sea. Ewen’s Ponds are about 15 kms from Mt Gambier, South Australia. Over the years the natural flow of Eight Mile Creek has been channelised and now follows a more direct course.

A recent public outcry over the decline of Ewens has seen the establishment of a technical reference group. Comprised of various government representatives the group will investigate and determine management strategies to improve its condition. Hopefully the recommendations and implementations of this group will not be too late for this precious ecosystem. We can only hope irreversible damage has not already occurred. Underwater experts, Ron and Valerie Taylor, have joined the public outcry over Ewens. Familiar with the unique dive spot since 1962, the creators of two documentaries about Ewens are dedicated to saving this pristine freshwater site.

‘We are extremely concerned by the rapid decline of these wetlands due to lack of understanding and serious mismanagement. Australian has only one Ewens Ponds. It is our duty to care for and preserve this magnificent gift of nature that belongs to us all equally and to not bleed it dry for the short term benefit of a few.’ The Ewens Pond system deserves to be fully protected and preserved for future generations. Its long term future will depend on the critical decisions we make.

Our suffering ecosystem
• More than 50% decline of water flow from Ewens Ponds to the ocean in the last 15 years, coinciding with an exponential growth in centre pivot use in the south east.
• Nutrient concentration more than 5 times safe environmental limits (ref EPA)
• Major decline in aquatic plant and fish life from the Ewens Pond system
• Evidence of hybridization of endangered fish species, possibly due to environmental stress.

 Underwater photographs of Ewens Ponds. At the same location in October 2002 and January 2006

More information
www.angfa.org.au/projects.htm

Ewens Ponds system Dredging