SGER: Does Manipulation of Top Predators Lead to Rapid Shifts in the Structure of Ecological Communities?

这个SGER项目将利用即将重新引入狐狸到圣米格尔岛，这是加州南部海岸外海峡群岛的一部分。 岛狐（Urocyon littoralis）于1998年从圣米格尔岛被移走。 狐狸被清除后，当地啮齿动物种群（由单一的鹿鼠属物种组成）急剧增加，密度达到每公顷900只以上--比附近有狐狸的圣克鲁斯岛的密度高出30倍。 有证据表明，圣米格尔岛上狐狸的消失和啮齿动物猎物的急剧增加导致了植物群落的迅速变化。 该SGER将允许对圣米格尔上的小型哺乳动物猎物群落进行实时跟踪，以应对重新引入的狐狸，并将狐狸对植物群落的直接和长期影响作为中心焦点。 对比将包括圣米格尔之前和之后的狐狸重新引入，与圣尼古拉斯岛，狐狸已经存在了至少2000年，和圣巴巴拉岛，狐狸从来没有出现（至少最近）。 该方法将是使用围隔来操纵捕食者和啮齿动物的访问，以量化自上而下的影响，植物群落在不同的捕食者的历史，以及不同的当代捕食者的活动（即重新引入圣米格尔岛）。 该项目的广泛应用可能相当大，特别是考虑到群岛有数百种稀有和濒危植物。 因为公园管理局负责监督海峡群岛，所以有机会与公园志愿者进行外联，并为任何结果提供一些相当不寻常的渠道。 这项研究将支持一名女研究生。

This SGER project would capitalize upon the imminent reintroduction of foxes to San Miguel Island, part of the Channel Islands off the coast of southern California. The Island Fox (Urocyon littoralis) was removed from San Miguel Island in 1998. Following fox removal, the native rodent population (consisting of a single Peromyscus species) has shown dramatic increases, attaining densities of over 900 mice per hectare - thirty times greater than densities on nearby Santa Cruz Island where fox are present. There is some evidence that the removal of foxes on San Miguel and the dramatic increase in their rodent prey led to rapid changes in the plant community. This SGER would allow the real-time tracking of the small mammal prey community on San Miguel in response to reintroduced foxes, with the immediate and longer term effects that foxes have on the plant community a central focus. Contrasts will include San Miguel before and after fox reintroduction, with San Nicolas Island where foxes have been present for at least 2000 years, and Santa Barbara Island where foxes have never been present (at least recently). The approach would be to use exclosures to manipulate predator and rodent access in order to quantify top-down influences on plant communities across islands with different predator histories as well as different contemporary predator activity (i.e. the reintroduction on San Miguel). The broader applications of the project are potentially quite large, especially considering that the Islands have hundreds of species of rare and endangered plants. Because the Park Service is responsible for oversight of the Channel Islands, there is an opportunity for outreach with Park volunteers, and some fairly unusual outlets for any results. The research would support a female graduate student.