Ecologist Dr Hugh Pringle and Eurardy Reserve’s Elizabeth Lescheid describe the erosion problems in Bungabandi Creek at Eurardy Reserve.
Eurardy wildflowers. Photo Julian Fennessy.
The homestead complex at Eurardy Reserve is situated in the gentle valley that forms the headwaters of Bungabandi Creek. Most of the Bungabandi Creek system is on conservation lands as it spans Eurardy Reserve and Kalbarri National Park. The ‘creek’ is essentially a narrow valley floor that occasionally widens and then constricts on its way westwards, eventually dropping down into the Murchison River below.
The valley floor has been the focus of recent restoration work as it's been put under enormous pressure from hard-hoofed animals (sheep, goats), feral animals (rabbits, deer) and use by vehicles.
Originally the Bungabandi system would have been a heavily vegetated narrow valley carrying sluggish flows after rain down to the Murchison River, but the impact of grazing and feral animal pressure has resulted in a destabilised soil surface. The result is something like a tiled roof with downpipes channelling rainwater rapidly through the system. Rain is mostly lost before it can penetrate and revitalise the soil.
Carpet of flowers including blue pincushion, Eurardy Reserve. Photo Julian Fennessy.
Apart from the valley floor, Bungabandi Creek is probably the healthiest tributary system to the Murchison River. It supports an amazing mosaic of different habitats, from thick scrub to open grasslands and saltbush shrublands.
There are declared rare flora (orchids), and a Department of Conservation and Environment wildlife officer has identified signs of bilbies. The variety of habitats and food resources of the Bungabandi also supports an abundance of birds.
The restoration plan for the creek involves a technique known as ‘brushing’, where brush is placed in the water channels, as well as depositing gravel in the worst-affected areas. This ‘plugs’ the channels and slows the rapid flow of the water.
If this works – and it may take time, including ongoing repairs – the valley floor will return to its former glory as a critical drought refuge and wildlife corridor at a landscape scale. This work is being undertaken by the reserve staff with vital help from volunteers.
‘Brushing’ the creek: bring on the volunteers
In the height of summer, when the mercury was reaching the upper 40s on a regular basis, Matt Warnock, the reserve’s manager, began carting and tipping trailer loads of gravel close to trouble spots to begin ‘plugging’ Bungabandi Creek.
Eurardy wildflowers. Photo Julian Fennessy.
Once the gravel mounds had been formed, it was time for the next stage. It was time to call in the volunteers!
Over late March and early April, a team from Conservation Volunteers Australia arrived to help out with the first brushing work. The brush is placed in the water channels to slow down the flow. Using the handy tip trailer we cut and collected brush from the edges of fire tracks that needed clearing and hauled it to the creek.
Also where trees had grown too thickly through the creek itself, Matt cleared brush, with a chainsaw and we followed, picking up the brush then dragging and laying it in the problem areas or ‘plug points’.
This valuable start to the Bungabandi Restoration Project was continued during the recent working bee in May. Two hard-working and enthusiastic volunteers, Brian Crute and Herbie Titelus, made a return journey from Perth to Eurardy to help out for the duration.
Brush was cut from the side of access tracks and piled on the trailer. Photo Elizabeth Lescheid.
A local TAFE conservation land management class also joined in for a couple of days. Brush was collected and laid, some of the gravel mounds were touched up and many ‘plugs’ were put in to stop erosion.
It was wonderful to drive around at the end of the working bee, looking at all the ribbons of brush that so many people had helped to lay. In places, it looked as if the brush was flowing too.
When the drought-breaking rains finally came in late May, Matt and I went down to see how the plugs were working. The first mounds we came to had little puddles of water pooled behind them and the first brush piles had ripples of sand building up near some of the edges. Rounding the corner to one of the major strategic points, we spotted a huge puddle behind the mound.
Further on, both brush and mound had stopped the flow too. Everything was working as intended.
Loud calls from several different species of frogs added to the excitement. Emu and kangaroo tracks covered the muddy track where wheel ruts used to be. Bungabandi Creek restoration had definitely begun!
Turning to me, Matt said: ‘We’ve only just begun, you know!’ Then, grinning, he went on to reveal plans to continue the project throughout the following year.