Document ID: chunk:federal_register_of_legislation:F2025L00287:reg:3:p53
Version: federal_register_of_legislation:F2025L00287
Segment Type: reg
Provision Reference: reg 3 (pt 53/276)
Character Range: 215379–218366

has been extensive loss of vegetation cover and diversity on Norfolk Island through cattle (Bos taurus) grazing (Neuweger et al. 2001). Cattle grazing has documented impacts on plant species such as Achyranthes arborescens, Boehmeria australis australis, Elatostema montanum, Ptisana salicina, Meryta latifolia and Streblus pendulinus (Sykes & Atkinson 1998). In areas outside the national park and in some public reserves, the loss of native forest to livestock grazing has been followed by little or no regeneration of native plant species. Grazing, trampling and soil compaction by cattle continue to be significant threats to remnant and regenerating native vegetation and to the health of ecosystems, particularly in riparian areas. Additionally, cattle are vectors for the spread of seeds from introduced plants and mechanical transmission of plant pathogens. Grazing by farmed cattle and goats may pose a threat to some of the few remaining patches of lowland forest on Norfolk Island.
Almost all the native vegetation on Phillip Island was lost to grazing by goats, pigs and rabbits, and as a result the island's topsoil has been severely eroded (Hyder Consulting 2008). Since the eradication of these feral herbivores, there has been significant regeneration of vegetation, particularly in gullies where soil pockets and collected precipitation provide good conditions for plant growth. Habitat loss, soil compaction and erosion caused by grazing and burrowing rabbits all contributed to the decline of native reptiles (Cogger et al. 1993) and the suppression of plant species such as Anthosachne kingiana kingiana on Phillip Island (Sykes & Atkinson 1988).

Introduced invertebrate species
The Argentine ant (Linepithema humile) is one of the world's worst invasive species, having spread from its native habitat in South America to establish populations on six continents and many oceanic islands (Suarez et al. 2001). The threat abatement plan to reduce the impacts of tramp ants on biodiversity in Australia and its territories (DEH 2006) identified the Argentine ant as one of six national priority species.
The Argentine ant was identified on Norfolk Island in 2005, and an eradication program commenced in 2008. Work to date has found Argentine ant infestations in 16 spatially discrete areas covering approximately 460 ha of the island's 3,455 ha. Approximately 45% of the infested areas have undergone treatment to date. No specific data on the impacts of the Argentine ant on Norfolk Island's biota or agriculture have been documented, but the potential impacts of this globally‑dispersed invasive species are well known (such as interfering with pollination and seed dispersal, outcompeting native invertebrates and damaging crops). Because of their aggressive nature and need for protein-based food sources, Argentine ants may pose a significant threat to the majority of the island's vertebrates and invertebrates. At particular risk are ground-nesting seabirds and