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Click here to go back Details of this species in Ascension Is. Status: Alien Invasiveness: Invasive Occurrence: Established Source: Pickup, 1999 in Varnham, 2006 Arrival Date: 1830 Introduction: Intentional Species Notes for this Location: Rabbits were introduced to Ascension Island around 1820 as a food source (Ashmole & Ashmole in Bell & Boyle 2008). Rabbit numbers were estimated to be 5010 or less than 5 rabbits per hectare, which is considered low density (Bell & Boyle, 2008). Management Notes for this Location: A combination of ferret/cat control, disease and increased hunting kept the population on Ascension relatively low until recently. However it is thought that the eradication of cats in 2002-2004 released the rabbits from predation pressure which allowed numbers to increase again (Bell & Boyle 2008). The ultimate goal of rabbit control of Ascension is long term management to reduce the impacts of rabbits on the island. Bell and Boyle (2008) list the following as practical control methods for rabbits in St Helena: Trapping Shooting Repellents Rabbit-proof fencing Disease (Rabbit calicivirus disease (RCD)) Poisoning Bell and Boyle (2008) conclude that the best option for control involves targeted poisoning and trapping and settlements. Even though there is public concern about poisoning and is relatively labour intensive, it is thought to be the most effective control option at present. Intensive control should continue for three to five years, after which long term control programmes should be maintained. Monitoring is essential to measure the effectiveness of control and ensure populations are being kept at a minimum. Public education is also essential. For the full case study of rabbit control on Ascension Island please follow this link to Management of rabbits (Oryctolagus cuniculus) on Ascension: a case study. Location Notes: Ascension Island is an isolated oceanic island 9700ha in size located in the mid-Atlantic Ocean. The terrain of the island is rugged with the highest point of Green Mountain rising to 859m.Ascension is a British Overseas Territory and Dependency of St Helena. The island is of high conservation value as it is the breeding ground of large numbers of green turtles (Ashmole & Ashmole in Bell & Boyle 2008) and tropical seabirds including the endemic Ascension frigatebird (Fregata Aquila) and landbirds, including the endemic Ascension rail (Atlantisia elpenor)(Bell & Boyle 2008). Impacts: Reduction in native biodiversity: There are suggestions that rabbits may be affecting the ability of smaller sea bird species to recolonise the island (Pickup, 1999 in Varnham, 2006). Threat to endangered species: Rabbits are affecting re-establishment of the 'Critically Endangered (CR)' endemic Ascension Spurge (see Euphorbia origanoides). Rabbits have affected attempts at re-establishment of this plant by grazing and digging at the base of plants, possibly to feed on the roots. Similarly rabbits are affecting establishment of new colonies of the 'Near Threatened (NT)' fern (see Marattia purpurascens). Last Modified: 17/06/2008 9:57:28 a.m.