Abstract
Feral goats Capra hircus, considered among the world’s most destructive invasive mammals, were introduced to Aldabra Atoll, a UNESCO World Heritage site in the Seychelles, before 1878. An eradication programme to remove goats from Aldabra was initiated in 1987, after severe ecological impacts were recorded. Eradication and control efforts continued intermittently for the next 20 years, and a final campaign was launched in 2007 using the Judas goat method. We present the methods, eradication dynamics, outcomes and financial costs of the final eradication campaign between 2007 and 2012. This effort was divided into three phases; (1) establishment of Judas goats and intensive hunting (4 months); (2) monitoring of Judas goats (4 years); and (3) Judas goat elimination and verification of success (8 months). In the focal 5-year period, 227 goats were culled (of 2297 across the entire 25-year period); 202 in phase 1, 21 in phase 2, and four remaining Judas goats in phase 3. The eradication was completed and confirmed successful in August 2012, following the use of multiple measures to confirm the absence of goats. The total cost of the eradication was US$ 185,105, an average of US$ 815/goat, or US$ 31/ha. The eradication, although ultimately successful, posed a unique combination of challenges. We discuss key lessons learned and put the project in context of other major island goat eradications. The financial details, context and lessons are expected to be of value to future practitioners.
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Acknowledgements
This achievement has only been possible with the dedication and hard work of a large team of people over many years. We’d like to thank all of the staff who braved the extreme heat, harsh terrain, mosquito infestations, basic camp conditions, and stagnant water to contribute to this success. These staff include: Stan Denis, Andy Gouffe, Israel Labrosse, Alex Underwood, Catherina Onezia, David Boodna, Uzice Samedi, Mike Marianne, Curtis Baker, Terence Mahoune, Michel Malbrook, Murvin Green, Richard Jeanne, Nella Victor, Martijn van Dinther, Jakawan Hoareau, Ritval Pillay, Naomi Doak, Bevil Narty, Aurelie Duhec, Roland Duval, Richard Baxter, Sam Balderson, Ian Valmont, and Malik Maiche. We thank Aldabra logistical staff, especially Island Manager Joel Souyave, senior skipper Jude Brice, and other staff members who covered work and rearranged schedules to prioritise the goat work. Many thanks to the other members of the original 2007 hunting team Herman Kant and Philippa Schultz, to Karl Campbell for his valuable advice and help in the planning stages, to Tom Smith for his vital help with the re-collaring efforts at a critical stage. Logistical and administrative support from SIF Head Office staff was essential throughout, particular thanks to Annabelle Constance and Felix Francourt for sourcing of equipment. Thanks to the Seychelles People’s Defence Force for staff support. A special thanks to the SIF Chairman Mr Maurice Loustau-Lalanne, the SIF Board of Trustees and Scientific Sub-Committee members for prioritising this project for 5 years. We are also grateful for all of the external and internal input advice, support and help with communications from a great many people. The eradication was funded by the Seychelles Islands Foundation and completed with financial support from the European Union under Project DCI-ENV/2010/220-252: “Mainstreaming the management of invasive species as fundamental to preserving the ecological integrity and enhancing the resilience of Seychelles’ World Heritage Sites”.
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Bunbury, N., von Brandis, R., Currie, J.C. et al. Late stage dynamics of a successful feral goat eradication from the UNESCO World Heritage site of Aldabra Atoll, Seychelles. Biol Invasions 20, 1735–1747 (2018). https://doi.org/10.1007/s10530-017-1657-0
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DOI: https://doi.org/10.1007/s10530-017-1657-0