Feral Horses and Their Environmental Impacts in the Australian Alps: Policy and Management Priorities

Feral horses (Equus caballus) are listed as a Key Threatening Process (KTP) under federal and state conservation policies, leading to active state government management programs aimed at reducing feral horse populations in ecologically sensitive regions (Tables 1 and 2). Program and expert reporting shows benefits for water, vegetation, soil, waterbirds and native fish from horse removal in these systems (Rowland, Moore, and Walsh 2023; Just et al. 2025). The NSW Government's Kosciuszko Wild Horse Heritage Act 2018 diverges from the policies of other States, and conflicts with the NSW KTP listing, by mandating retention of 3000 horses in one third of Kosciuszko National Park. This is despite extensive scientific evidence of the environmental harm caused by feral horses in Kosciuszko National Park, across other alpine, subalpine and riverine regions (Figure 1), and in other ecosystems (Nimmo and Miller 2007; Driscoll et al. 2019; Stobo-Wilson et al. 2020). Just, K., Bennetts, K., & Wright, T. (2025). The Living Murray Barmah-Millewa Wetland Vegetation Condition Monitoring 2024 Annual Report. Consultant report to Goulburn Broken Catchment Management Authority, Shepparton. Murray-Darling Basin Authority (2025). Barmah–Millewa Forest Report Card 2023–24. Report by the Australian Government Murray-Darling Basin Authority. Studies show deleterious impacts of livestock grazing on alpine ecosystems and their conservation values. Grazing resulted in very high levels of damage to vegetation and soils, requiring $10 M taxpayer investment in rehabilitation in the Australian Alps There is no evidence to support previous claim that horses “can roam without causing significant environmental harm” as they are free ranging and cannot be kept in one place away from sensitive ecosystems, they graze selectively often in rare and endangered grasslands and herbfields, travel long distances that results in soil and water degradation, and damage wetlands when they visit them to drink Habitat degradation and loss by Feral Horses (brumbies, wild horses), Equus caballus Linnaeus 1758, listed as a Key Threatening Process in Schedule 4 of Biodiversity Conservation Act 2016. Kosciuszko Wild Horse Heritage Act 2018 (protects a nominated “heritage” herd) Recognised as feral animal & threat to native species—degradation and loss of habitats caused by feral Horses (Equus caballus) listed as a Potentially Threatening Process under Victorian Flora and Fauna Guarantee Act 1988 Not classified as pests under Catchment and Land Protection Act 1994 Determined to be an Established Species of National Significance Not declared as pest to agriculture or biosecurity threat under Pest Plants and Animals Act 2005 or Biosecurity (Pests) Declaration 2025 Complete removal via culling of feral horses from threatened alpine and subalpine ecosystems, including peatlands and wetlands, is recommended (Beeton and Johnson 2019). Excluding horses from sensitive locations (e.g., through fencing), or using fertility control methods, is insufficient for preserving ecological function and connectivity of sensitive ecosystems such as alpine peatlands and wetlands (Driscoll et al. 2019; Hobbs and Hinds 2018). Horse control must be coordinated with integrated fire and pest management strategies addressing other invasive herbivores and omnivores, weeds and invasive predators (Keith et al. 2022; Rowland, Walsh, et al. 2023). Restoration, including moss layer transfers and hydrological repair in peatlands, may reverse some damage and recover lost carbon storage capacity once horses are removed (Treby and Grover 2023). Uncensored evidence-based communication of feral horse impacts by State agency staff, independent scientists and political leaders is essential to make the cost of inaction clear (Nimmo and Miller 2007). The evidence is unequivocal: feral horses present a significant ecological threat to Australia's alpine and subalpine environments. Legislation that supports effective feral horse control throughout national parks and other public land designated for conservation purposes must be in place. Open access publishing facilitated by Queensland University of Technology, as part of the Wiley - Queensland University of Technology agreement via the Council of Australian University Librarians. The authors declare no conflicts of interest. The data that supports the findings of this study are available in the Supporting Information of this article. Data S1: aec70117-sup-0001-DataS1.xlsx. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.