Re-establishment of ecosystem engineers via introduction of replacement species is increasingly being proposed to facilitate ecosystem restoration of island ecosystems around the world, yet attendant challenges and risks remain largely unknown. We evaluate the first phase (2015–2020) of a program to restore a population of giant tortoises, ecosystem engineers of terrestrial ecosystems of the Galapagos Islands, to Santa Fe Island during which a total of 551 juvenile and 31 subadult tortoises of the non-native Española Island species (Chelonoidis hoodensis) were translocated. After 5 years, most (85%) of tortoises released remain alive, exhibiting robust vital rates comparable to those of conspecifics in their native range, having colonized 10% of the island via gradual dispersal from the point-of-release. Populations of an arboreal cactus (Opuntia echios)—a keystone species for many organisms on the island and intended beneficiary of tortoise restoration—and pallid land iguanas (Conolophus pallidus)—an endemic, herbivorous reptile considered potentially at risk from the introduction of tortoises, both increased coincident with the arrival of tortoises. Herbivore exclosure experiments revealed that the island's plant community manifested a response to the arrival of tortoises; however, significant engineering of the island's vegetation will require many decades. These results highlight the first stage of what appears to be a successful conservation intervention that can serve as a “proof of concept” for introduction of ecological replacements to other islands in Galapagos, and potentially for other island ecosystems around the world.

中文翻译：

---

引入巨龟作为替代“生态系统工程师”，以促进加拉帕戈斯圣达菲岛的恢复

越来越多的人提议通过引入替代物种来重建生态系统工程师，以促进世界各地岛屿生态系统的生态系统恢复，但随之而来的挑战和风险在很大程度上仍然是未知的。我们评估了一项计划的第一阶段（2015-2020 年），该计划旨在将加拉帕戈斯群岛陆地生态系统的生态系统工程师、加拉帕戈斯群岛陆地生态系统的生态系统工程师群体恢复到圣达菲岛，在此期间，共有 551 只幼龟和 31 只亚成年陆龟。西班牙本土物种 ( Chelonoidis hoodensis)) 被转移。5 年后，大多数 (85%) 被释放的陆龟仍然活着，表现出与原生范围内的同类物种相当的强大生命率，通过从释放点逐渐分散在岛上 10% 的土地上定居。树栖仙人掌 ( Opuntia echios ) 的种群 - 岛上许多生物的基石物种，也是陆龟恢复的预期受益者 - 和苍白的陆鬣蜥 ( Conolophus pallidus)——一种地方性的草食性爬行动物，被认为可能因陆龟的引入而面临风险，两者都随着陆龟的到来而增加。草食动物封闭实验表明，岛上的植物群落对陆龟的到来做出了反应；然而，岛上植被的重大工程将需要数十年的时间。这些结果突出了似乎是成功的保护干预的第一阶段，可以作为将生态替代引入加拉帕戈斯其他岛屿的“概念证明”，并可能用于世界各地的其他岛屿生态系统。