Drought as a teacher: The strategic value of wetlands of the Discovery Bay coast is now being brought into sharp focus

For anyone who lives in western Victoria or southern SA, I don’t need to tell you how dry it has been!

The local stories of dry dams, springs and bores, empty rainwater tanks, dying trees and parched dry ground in place of usually semi-permanent wetlands tell the story of the past couple of years incredibly dry conditions.

Where I live in western Victoria, no one from the older generation ever remembers it being this dry before, and this is backed up by the long-term climate data. It is also reflected by the fact that almost all of the freshwater wetlands across the wider region, on both sides of the border, are now well and truly dry. For example, high-profile NGT wetland restoration sites shown below like Walker Swamp, which had been inundated continuously since 2019, as well as Green Swamp and Mt Burr Swamp, which have both been permanently inundated since 2016, are now all completely dry for the first time since they filled after restoration.

But if we pay attention, drought can also be a great teacher, and it may surprise you to learn that right now there are a small subset of fresh wetlands – fed by groundwater – that are offering incredibly valuable drought refuge habitat.

In the zone experiencing the most severe drought conditions at the moment, NGT have had a hand in restoring groundwater fed wetlands that are bucking the current trend. On the Fleurieu Peninsula south of Adelaide, sites like Square Waterhole Swamp and Glenshera Swamp (as discussed by Tessa in her article here) are groundwater seepage fed peat swamps that – aided by restoration works to prevent desiccation of the peat – now remain saturated, while in far south-western Victoria, NGT’s decade-long restoration project at Long Swamp, in Discovery Bay Coastal Park, is also currently illustrating its immense strategic landscape value by remaining inundated.

In fact, I had the benefit of visiting the site of NGT’s Long Swamp restoration project site in Discovery Bay Coastal Park recently (for the first time since December, when I predicted this site would provide valuable drought refuge habitat this year), and here is what I saw…

Long Swamp at this location has now been continuously inundated for 10 years, since 2015, providing vital additional drought refuge habitat and – by reinstating flows towards the Glenelg River – increasing water availability and security to other now permanent wetlands situated further downstream (to the west) in Long Swamp.

I also ended up visiting another nearby restoration site on the same day – Pick Swamp – a project I conceived and oversaw 20 years ago when I worked for the SA Government, prior to NGT coming onto the scene in 2012. Now part of Piccaninnie Ponds Conservation Park, Pick Swamp is former drained farmland that lies within the SA portion of the Discovery Bay coast, and is another outstanding, groundwater-fed drought refuge site.

This property was purchased in 2005 by the SA Government, and has sustained permanent inundation now for 18 years, since restoration works began in 2007. Indeed, the success of the project at this site, and the desire to replicate these amazing outcomes more broadly elsewhere, was actually one of the key motivations for my decision to take the leap all those years ago and assemble a team in 2011 to start up NGT!

The incredible bird list for this wetland that has been collated over the years by the local Birdlife SE SA group, speaks volumes for the vital role these interconnected Discovery Bay wetlands are playing in the landscape. Here is what Pick Swamp looked like when I visited the other day…

While periodic drying is part of the natural cycle for many wetland types (noting that those wetlands mentioned above which have dried out will all bounce back), there are an increasingly rare and restricted number of wetlands that never dry out, which makes those sites more important than ever. Right now these sites are demonstrating their immense strategic value for biodiversity protection, because a wide range of both less mobile species (e.g. freshwater fish and crayfish) and more mobile species (e.g. birds and bats) require access to secure aquatic habitat when times get really tough in the wider landscape.

In the case of both Pick Swamp and Long Swamp, while they are situated within listed Wetlands of International Importance under the Ramsar Convention – the Piccaninnie Ponds Karst Wetlands and Discovery Bay and Glenelg Estuary Ramsar sites respectively – this status alone doesn’t appear to automatically guard against all potential threats, particularly those that occur upstream or on nearby land.

More than ever, against the backdrop of a changing climate, the immense value of these wetlands requires appropriate recognition by all levels of government, to ensure that these sites (and the movement pathways of the species that frequent them) are offered the highest and broadest level of policy protection. We must apply adequate caution, to proactively guard against any nearby activities that risk compromising their biodiversity values or future water security.

PS: By the way, if you would like to discover more about the restoration story of these wetlands, you can learn more by clicking on the relevant link below:

• Pick Swamp (click this link to see the pdf document)
• Long Swamp (click this link to see the pdf document)