REDONDA RESTORATION PROGRAMME: Technical report on the final check following the eradication of black rats (Rattus rattus) from Redonda, Antigua & Barbuda, June‐July 2018 Cover illustration: Magnificent frigatebirds, Fregata magnificens, on their nest sites on Redonda (Photo: Elizabeth Bell, WMIL). THE OPINIONS OF THE AUTHORS DO NOT NECESSARILY REFLECT THE OPINIONS OF THE PARTNER ORGANISATIONS OF THE REDONDA RESTORATION PROGRAMME. PUBLISHED BY: Redonda Restoration Programme, St. John’s, Antigua RECOMMENDED CITATION: Bell, E.A. & Challenger, S. (2018) Technical report on the final check following the eradication of black rats Rattus rattus from Redonda, Antigua and Barbuda, June‐July 2018. Report from Wildlife Management International Ltd and Fauna & Flora International to the Redonda Restoration Programme, St John’s, Antigua and Barbuda. Author details: Ms. Elizabeth ‘Biz’ Bell Ms. Shanna Challenger Senior Ecologist Redonda Restoration Programme Coordinator Wildlife Management International Ltd Department of Environment/Environmental PO Box 607, Awareness Group/Fauna & Flora International Blenheim 7240 St John’s New Zealand Antigua www.wmil.co.nz Email: shanna.challenger@fauna‐flora.org Email: [email protected] All photographs in this report are copyright ©WMIL unless otherwise credited, in which case the person or organization credited is the copyright holder. The Redonda Restoration Programme was launched in 2016 by the Government of Antigua and Barbuda, Environmental Awareness Group, British Mountaineering Council, Fauna & Flora International, Island Conservation and Wildlife Management International Ltd. This partnership is working to rehabilitate Redonda into a healthy island ecosystem that is sustainably managed for the conservation of indigenous biodiversity, and to preserve Redonda’s important historical values and facilitate the sustainable use and enjoyment of Redonda by present and future generations. The development of this plan was funded by the National Fish and Wildlife Foundation and Darwin Initiative (#23‐003: Eradicating Invasive Species from the Highest Priority Caribbean Island). EXECUTIVE SUMMARY 1. Redonda has been internationally recognised as an Important Bird Area and supports rare and unique animals and plants of both national and global importance, including seabirds such as magnificent frigatebird Fregata magnificens, masked booby Sula dactylatra, red‐ footed booby S. sula and brown booby S. leucogaster, as well as smaller numbers of red‐ billed tropic bird Phaethon aethereus, brown noddy Anous stolidus and bridled tern Sterna anaethetus and endemic reptiles such as the Redonda ground lizard Philodoscelis atrata and Redonda tree lizard Anolis nubilus and an unnamed dwarf gecko (Sphaerodactylus sp.). 2. The Redonda Restoration Programme (RRP) is a collaborative programme of the Government of Antigua & Barbuda, Environmental Awareness Group (EAG), Fauna & Flora International (FFI), British Mountaineering Council (BMC), Wildlife Management International Ltd (WMIL) and Island Conservation (IC), with support from Darwin Initiative through UK Government funding, National Fish & Wildlife Foundation, Taurus Foundation, Global Wildlife Conservation, Syngenta Crop Protection AG and Caribbean Helicopters Ltd. 3. This partnership is working to rehabilitate Redonda into a healthy island ecosystem that is sustainably managed for the conservation of indigenous biodiversity, and to preserve Redonda’s important historical values and facilitate the sustainable use and enjoyment of Redonda by present and future generations. 4. Redonda had a large population of invasive alien black rats (Rattus rattus). Together with feral goats (Capra hircus, which were relocated in 2018), these rodents were heavily implicated in the severe and ongoing decline of the island’s vegetation and native wildlife populations, and a number of species have become extinct. The once‐forested island had reached advanced stages of desertification. 5. The eradication of black rats from Redonda was completed between 13 February and 7 April 2017 using a combination of ground‐based bait station and aerial methods was led by island restoration specialists from Wildlife Management International Ltd with a team of nine volunteers over the ten‐week project. 6. Long‐term monitoring was carried out between April 2017 and May 2018 by RRP personnel. 7. The final check was carried out by Wildlife Management International Ltd. personnel and RRP staff and volunteers. 8. Monitoring during the final check consisted of flavoured wax (peanut, chocolate and aniseed), tracking tunnels and trail cameras in a combination of closed lockable biosecurity stations and points in the open over the island (n = 169 stations, excluding biosecurity stations). 9. There were between 1 and 5 complete checks (depending on the areas, i.e. coastline, cliff scramble or top) done over 18 days. 10. Rats were not detected on any monitoring station or at any location on Redonda. 11. Redonda was declared rat‐free on 31 July 2018. 12. Ongoing monitoring of the 39 biosecurity stations on the island will continue indefinitely as part of the biosecurity requirements to maintain the rodent‐free status of Redonda. These biosecurity requirements will be the responsibility of the RRP personnel with support from Fauna & Flora International and other trained personnel when visiting the island. Bell & Challenger i 13. RRP, EAG and Department of Environment (DOE) staff and volunteers were trained in safe rodenticide use, long‐term monitoring, biosecurity and rodent detection techniques. 14. Research and monitoring of the seabirds, land birds, reptiles and vegetation will continue after the eradication programme to assess the effects of removing rats on the Redonda ecosystem. RRP, EAG and DOE staff and volunteers and other researchers will undertake this work with technical support from Fauna & Flora International. 15. The operation on Redonda has shown that a well‐planned, adequately resourced, well‐ executed programme, with the complete support of partner agencies and other stakeholders and led by an experienced operator with dedicated volunteers means total eradication of rats is possible on islands with difficult access and very steep terrain. 16. The eradication of black rats from Redonda is a major achievement and will provide the opportunity to restore and enhance the reptile, bird and other native species communities of the island. Bell & Challenger ii TABLE OF CONTENTS EXECUTIVE SUMMARY i TABLE OF CONTENTS iii ACKNOWLEDGEMENTS iv TECHNICAL REPORT OF THE FINAL CHECK FOLLOWING THE ERADICATION OF BLACK RATS (RATTUS RATTUS) FROM REDONDA, ANTIGUA & BARBUDA 1 1 INTRODUCTION 1 1.1 REDONDA 2 2 GOAL AND OBJECTIVE OF REDONDA RAT ERADICATION 5 3 METHODS 5 4 RESULTS 9 4.1 OTHER OBSERVATIONS DURING THE FINAL CHECK ON REDONDA 11 4.1.1 LIZARD OBSERVATIONS 11 4.1.2 BIRD OBSERVATIONS 11 4.1.3 VEGETATION OBSERVATIONS 12 4.1.4 GOAT OBSERVATIONS Error! Bookmark not defin 5 CONCLUSIONS 13 6 RECOMMENDATIONS 14 7 REFERENCES 14 8 APPENDICES 18 8.1 TIMETABLE OF ACTIVITIES FOR THE REDONDA FINAL CHECK (14 JUNE TO 2 JULY 2018) 18 Bell & Challenger iii ACKNOWLEDGEMENTS This work was carried out under the auspices of the Redonda Restoration Programme (RRP), a collaborative programme of the Government of Antigua and Barbuda, Environmental Awareness Group (EAG), British Mountaineering Council (BMC), Fauna & Flora International (FFI), Island Conservation and Wildlife Management International Ltd (WMIL). This programme was launched in 2016 with funding from Darwin Initiative through UK Government funding (grant #23‐003), National Fish & Wildlife Foundation, Global Wildlife Conservation, Taurus Foundation, Betty Liebert Trust, Waitt Foundation and additional technical and material support from Caribbean Helicopters, Syngenta Crop Protection AG and Bell Laboratories Inc. Additional staff time, international flights and equipment were provided by Fauna & Flora International (FFI) and Wildlife Management International Ltd. The authors would like to thank to the following people and organisations: The Government of Antigua and Barbuda—in particular the Ministry of Health, Wellness and the Environment and the Veterinary and Livestock Division under the Ministry of Agriculture, Fisheries and Barbuda Affairs—for their kind permission to conduct field work and for their interest, support, advice and in‐kind assistance throughout the development of this component of the RRP. Salina Janzan, Adam Long and Waldo Etherington, for their hard work during the Final Check phase. Jack Ibbotson, Chris Clarke, Thea Eldred, James Stops, Salina Janzan, Silas Walton, Bede West, John Tayton and Edward Marshall for their hard work, enthusiasm and support during the rat eradication phase; the success of the project so far, and in the future, is a credit to them. Carolyn Thomas, for her help with plant identification and assistance in the field when on Redonda. Sophia Steele, FFI Eastern Caribbean Coordinator, for her assistance with the logistical arrangements on Antigua, assistance in the field and ongoing support of the project. Jenny Daltry, FFI, Senior Conservation Biologist, for her assistance with all phases of the Redonda Restoration Programme, review of this report and continuing advice for the project. Natalya Lawrence, Coordinator, Offshore Islands Conservation Programme, EAG, for her support of the project. The team at Caribbean Helicopters for their ongoing support of the project. We also thank other individuals for peer‐reviewing this plan.