Details of this species in Macquarie Is. (sub-Antarctic) Status: Alien Invasiveness: Invasive Occurrence: Established Source: Parks and Wildlife Service. 2006; Tasmania National Parks Association Inc. 2006. Arrival Date: 1870 Introduction: Intentional Species Notes for this Location: European rabbits were released by sealers in the 1870s as an additional food source (Cumpston 1968, in Parks and Wildlife Service. 2006). They are now found throughout the island. In 1978 the overwintering population was estimated at 150 000 rabbits (Copson et al. 1981, in Parks and Wildlife Service. 2006). In December 1978 control measures were begun using myxomatosis. The estimated population in 2002 was 16 000 (Copson 2002, in Parks and Wildlife Service. 2006). Management Notes for this Location: The Macquarie Island Nature Reserve and World Heritage Area Management Plan 2006 (Parks and Wildlife Service. 2006) identifies the eradication of rabbits, rats and mice from the island as one of the highest conservation priorities in the reserve. The 2006 Macquarie Island Nature Reserve and World Heritage Area Management Plan recommends that until such time as a combined rabbit and rodent eradication program can be undertaken, rabbit control should be continued and given a high priority, and the myxoma virus and other most effective available control methods should be utilised. Please follow this link to see the just published (March 2007) Plan for the Eradication of Rabbits and Rodents on Subantarctic Macquarie Island A threat abatement plan has been produced by the Department of Environment and Heritage that is relevant to the management of alien species of Macquarie Island. It is entitled: The Threat Abatement Plan for Competition and Land Degradation by Feral Rabbits (1999). Location Notes: Macquarie Island Nature Reserve is one of the most valuable reserves in the world, well recognised for its conservation, geological, ecological and scientific values. It is a World Heritage Area, a Biosphere Reserve, and on the Register of the National Estate (Parks and Wildlife Service 2006). Macquarie Island is a breeding ground for nearly four million seabirds, including two threatened albatross species: the wandering and grey-headed albatross (Tasmania National Parks Association Inc. 2006b). Impacts: Economic/Livelihoods: Loss of tourism value. A landslide believed to be caused by heavy rabbit grazing in September 2006 adjacent to Sandy Bay staircase forced the closure of the staircase, boardwalk and Royal penguin viewing platform (key visitor infrastructure) (Tasmania National Parks Association Inc. 2006). Ecosystem change: Rabbits, rats and mice are causing extensive impacts on the biodiversity and landscape of the Macquarie Island Nature Reserve (Parks and Wildlife Service 2006). Rabbits are key drivers of ecosystem change. The drive at least two key threatening processes on Macquarie Island; one is their impact on vegetation (tall tussock grassland and herbfields), the second is their alteration of valuable seabird habitats via increasing soil instability and erosion processes (Parks and Wildlife Service 2006). Rabbits are known for their ability to heavily graze vegetation, destroyed some tall tussock grassland areas and converting them to short grassland or mire (Copson 1984, Scott 1988, in Parks and Wildlife Service 2006). Some plant species, such as Pleurophyllum hookeri and Stilbocarpa polaris, are so heavily grazed by rabbits that they have become locally extinct from some sites on the island (Parks and Wildlife Service 2006).
It is thought that habitat alteration by rabbits, as well as predation by skuas and introduced cats, wekas and rats, have greatly reduced or even eliminated populations of some of the smaller species of prion and petrel which once bred in the reserve (Brothers 1984, Brothers and Copson 1988, in Parks and Wildlife Service 2006).
Soil stability is a key environmental variable in the Macquarie Island Nature Reserve which is affected partly by rabbit grazing, and also by continual winds, seismic activity, freezing and thawing and constant precipitation (Parks and Wildlife Service 2006). Habitat alteration: In Sandy Bay Healthy green tussock vegetation is being replaced by dead brown stumps due to rabbit grazing (Tasmania National Parks Association Inc. 2006). Physical disturbance: Macquarie Island’s largest king penguin (see Aptenodytes patagonicus in IUCN Red List of Threatened Species) colony, found at Lusitania Bay, was threatened by a landslide which occurred in September 2006 and which was thought to be due to a combination of heavy rainfall and rabbit grazing which increased the instability of the land. The landslide buried some penguins alive and destroyed part of the colonies habitat (Tasmania National Parks Association Inc. 2006). Last Modified: 18/04/2007 4:01:38 p.m.
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