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Archipelago-Wide Island Restoration in the Galápagos Islands: Reducing Costs of Invasive Mammal Eradication Programs and Reinvasion Risk

By Victor Carrion, C. Josh Donlan, Karl J. Campbell, Christian Lavoie and Felipe Cruz

Abstract

Invasive alien mammals are the major driver of biodiversity loss and ecosystem degradation on islands. Over the past three decades, invasive mammal eradication from islands has become one of society's most powerful tools for preventing extinction of insular endemics and restoring insular ecosystems. As practitioners tackle larger islands for restoration, three factors will heavily influence success and outcomes: the degree of local support, the ability to mitigate for non-target impacts, and the ability to eradicate non-native species more cost-effectively. Investments in removing invasive species, however, must be weighed against the risk of reintroduction. One way to reduce reintroduction risks is to eradicate the target invasive species from an entire archipelago, and thus eliminate readily available sources. We illustrate the costs and benefits of this approach with the efforts to remove invasive goats from the Galápagos Islands. Project Isabela, the world's largest island restoration effort to date, removed >140,000 goats from >500,000 ha for a cost of US$10.5 million. Leveraging the capacity built during Project Isabela, and given that goat reintroductions have been common over the past decade, we implemented an archipelago-wide goat eradication strategy. Feral goats remain on three islands in the archipelago, and removal efforts are underway. Efforts on the Galápagos Islands demonstrate that for some species, island size is no longer the limiting factor with respect to eradication. Rather, bureaucratic processes, financing, political will, and stakeholder approval appear to be the new challenges. Eradication efforts have delivered a suite of biodiversity benefits that are in the process of revealing themselves. The costs of rectifying intentional reintroductions are high in terms of financial and human resources. Reducing the archipelago-wide goat density to low levels is a technical approach to reducing reintroduction risk in the short-term, and is being complemented with a longer-term social approach focused on education and governance

Topics: Research Article
Publisher: Public Library of Science
OAI identifier: oai:pubmedcentral.nih.gov:3092746
Provided by: PubMed Central

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Citations

  1. (2010). Aliens, globalization, and biodiversity.
  2. (2009). Bio-economics of large-scale eradication of feral goats from Santiago Island, Galapagos.
  3. (2005). Conservation action in the Gala ´pagos: Feral pig (Sus scrofa) eradication from Santiago Island.
  4. (2007). Development of a prolonged estrus effect for use in Judas goats.
  5. (2010). Eradication of feral cats on Faure Island,
  6. (2004). Eradication of feral goats Capra hircus from Pinta Island, Gala ´pagos,
  7. (2011). Eradication of invasive mammals on islands inhabited by humans and domestic animals. Conservation Biology:
  8. (2002). Eradication: The clearance of Campbell Island.
  9. (2007). Establishing causes of eradication failure based on genetics: Case study of ship rat eradication in Ste. Anne archipelago.
  10. (2007). Facing the dilemma at eradication’s end: uncertainty of absence and the lazarus effect.
  11. (2007). Feral donkey (Equus asinus) eradication in the Gala ´pagos.
  12. (1994). Feral goat eradication of San Clemente Island,
  13. (2005). Feral goat eradications on islands.
  14. (2007). Geographic tools for eradication programs of insular non-native mammals.
  15. (2006). Have the harmful effects of introduced rats on islands been exaggerated?
  16. (2008). High-impact conservation action: invasive mammal eradication from the islands of western Mexico.
  17. (2005). Increasing the efficacy of Judas goats by sterilisation and pregnancy termination.
  18. (2007). Invasive rodent eradication on islands.
  19. (2007). La flora edemica de Galapagos: aumentan las especies amenazadas.
  20. (2007). Manipulation of the reproductive system of feral goats (Capra hircus) to increase the efficacy of Judas goats: field methods utilising tubal sterilisation, abortion, hormone implants and epididymectomy.
  21. (1997). Plan for the protection of northern Isabela Island, Gala ´pagos National Park, Ecuador, from ecosystem damage caused by feral ungulates. Charles Darwin Research Station/Gala ´pagos National Park Service, Puerto Ayora, Santa Cruz, Gala ´pagos Islands.
  22. (2011). Planning processes for eradication of multiple pest species on Macquarie Island - an Australian case study.
  23. (2011). Quantifying the success of feral cat eradication,
  24. (1988). Radio telemetry as an aid in eradicating remnant feral goats.
  25. (2007). Recovery of the Gala ´pagos Rail (Laterallus spilonotus) following the removal of invasive mammals.
  26. (1999). Restoration of insular ecosystems: control of feral goats on Aldabra Atoll, Republic of Seychelles.
  27. (2008). Rewilding the islands. In: Fearn E, Redford K, eds. State of the wild 2008–09: A global portrait of wildlife, wildlands, and oceans.
  28. (2008). Severity of the effects of invasive rats on seabirds: a global review.
  29. Simban ˜a W (2008) The consequences of herbivore eradication on Santiago: are we in time to prevent ecosystem degradation again? In:
  30. (2008). Testing island biosecurity systems for invasive rats.
  31. (2011). The diet of feral cats on islands: a review and a call for more studies.
  32. (2011). The global islands invasive vertebrate eradication database: a tool to improve and facilitate restoration of island ecosystems.
  33. (1990). The impact of introduced herbivores on the Galapagos rail (Laterallus spilonotus).
  34. (2007). The thematic atlas of Project Isabela. An illustrative document describing, step-bystep, the biggest successful goat eradication project on the Galapagos Islands 1998–2006. Puerto Ayora, Gala ´pagos Islands: Charles Darwin Foundation.
  35. Turning the tide: the eradication of invasive species.