The electrified exclusion fence at Wild Horse Plain, north of Kiandra, was built to protect 108 hectares of endangered alpine wetlands from wild horses. Photo: Supplied.
A large fence stretching across open country at Wild Horse Plain in Kosciuszko National Park (KNP) was built to protect 108 hectares of endangered alpine wetlands, the NSW National Parks and Wildlife Service (NPWS) has confirmed.
The new enclosure, north of Kiandra, had prompted widespread questions from park users about what was being protected and speculation that it might be connected to a sinkhole, subsidence or other ground instability associated with Snowy 2.0.
Closely spaced black steel star pickets carry multiple electrified wires – with orange insulators running almost from ground level to the top strand – around a roughly square enclosure, with access gates, warning signs and solar-powered units positioned at intervals along its length.
A NSW Government contract notice shows the work was awarded to JD Keys and MJ Keys for an estimated $187,000, with the contract running from 1 February to 30 March 2026.
NPWS said the fence was constructed in March to protect alpine sphagnum bogs and associated fens, also known as montane peatlands and swamps, from the ongoing impacts of wild horses.
A Department of Climate Change, Energy, the Environment and Water technical report on peat-forming bogs and fens in the Snowy Mountains found they account for up to 2.5 per cent of the higher-altitude landscape in KNP.
The report says they occur along drainage lines and seepage areas, where waterlogged conditions slow the breakdown of plant material and allow peat to accumulate.
Their sphagnum moss and peat soils hold water and release it gradually into alpine streams, while the slowly forming peat preserves a record of past vegetation and fire.
NPWS said the wetlands also provided important habitat for threatened species including the broad-toothed rat, northern corroboree frog and stocky galaxias.
Alpine sphagnum bogs and associated fens are listed as endangered under both NSW and Commonwealth environmental laws.
NPWS said habitat damage caused by feral horses was formally recognised as a key threat under NSW environmental law.
A 2023 study of 12 alpine and subalpine peatlands in KNP also found sites used by wild horses were losing more carbon and had poorer soil and water conditions than horse-free sites.
Researchers Sarah Treby and Samantha Grover found carbon emissions were 91 per cent higher from bare ground than from areas still covered by sphagnum moss.
They said excluding horses could help protect the wetlands, improve soil and water conditions and preserve their ability to store carbon.
A warning sign marks a gate in the electrified exclusion fence built around 108 hectares of endangered alpine wetlands at Wild Horse Plain. Photo: Supplied.
While the Wild Horse Plain enclosure appears unusual within KNP, conservation fencing is already used elsewhere across the NSW national park estate.
In far south-east NSW, near the Victorian border, a 25-kilometre electrified predator-proof fence surrounds 2080 hectares at Nungatta in South East Forest National Park.
The enclosure forms part of an NPWS network of 10 feral predator-free areas designed to exclude introduced animals and allow threatened native species to recover or be returned to places where they have become locally extinct.
The Nungatta project is expected to benefit more than 13 threatened animal species and allow up to nine locally extinct mammals to be returned to the area.
The 2008 Kosciuszko National Park Horse Management Plan identified fencing as one of several methods available to exclude horses from sensitive areas, with the most suitable approach depending on factors including geography, season and the size of the mob.
It was superseded by the 2021 Kosciuszko National Park Wild Horse Heritage Management Plan (KNP WWHHMP), which was amended in 2023 and will remain in place until wild horse management is incorporated into an updated park-wide plan of management by November 2027.
Snowy Hydro says the Wild Horse Plain fence has no connection to Snowy 2.0 construction works, although its cost was met through biodiversity offsets tied to the project.
Biodiversity offsets are intended to compensate for environmental impacts associated with major developments that cannot be fully avoided or reduced.
Snowy Hydro confirmed a specially designed weir had been built on Tantangara Creek, near Tantangara Reservoir in northern KNP, under Snowy 2.0’s environmental approval conditions to prevent introduced fish entering stocky galaxias habitat.
It forms part of a broader program that also includes fine-mesh screens at the reservoir outlets and captive breeding and recovery work for stocky galaxias and Macquarie perch.
