LTREB: Long-term Response of an Ecosystem to an Invasive Species

外来物种（那些被人类迁移到其原生范围之外的物种）在世界各地具有巨大的生态和经济影响。 大多数对外来物种的研究都是在物种出现后不久进行的，那时科学和公众的兴趣最高。 然而，外来物种的影响可能会随着时间的推移而变化，随着外来物种和入侵生态系统的相互适应，或者随着外来物种的影响与其他控制因素（例如，气候）随时间而变化。 我们对斑马贻贝（一种欧洲入侵者）对哈德逊河生态系统的影响进行了长期研究，结果表明，这种入侵物种的影响可能会在长期内发生变化。 这些证据包括一些本地物种的部分恢复，斑马贻贝种群的大小和地理分布的变化，斑马贻贝影响减弱的过渡性“热点”的发展，以及斑马贻贝消耗藻类和淡水流量之间的强烈相互作用，这是对哈德逊生态系统的另一个重要控制。 我们建议继续我们的长期研究的哈德逊测试几个具体的假设之间的相互作用如何斑马贻贝和哈德逊的生态系统可能会随着时间的推移而变化。 这些信息将有助于更好地预测斑马贻贝对北美生态系统的真正长期影响，更好地了解对水生生态系统的控制，并更好地判断外来物种如何与它们入侵的生态系统相互作用。

Alien species (those moved outside of their native ranges by humans) have large ecological and economic effects around the world. Most studies of alien species are done soon after the species appears, when scientific and public interest is highest. However, the effects of an alien species may change over time, either increasing or decreasing, as the alien species and the invaded ecosystem accommodate to one another, or as the effects of the alien species interact with other controlling factors (e.g., climate) that change over time. Results from our long-term study of the effects of the zebra mussel (a European invader) on the Hudson River ecosystem suggest that the effects of this invasive species may be changing over the long term. Such evidence includes partial recovery of some native species, changes in the size and geographical distribution of the zebra mussel population, development of transitory "hot spots" where zebra mussel effects are diminished, and strong interactions between consumption of algae by zebra mussels and freshwater flow, another important control on the Hudson's ecosystem. We propose to continue our long-term study of the Hudson to test several specific hypotheses about how interactions between the zebra mussel and the Hudson's ecosystem might change over time. This information will help better predict the true long-term effects of zebra mussels on North America's ecosystems, better understand the controls on aquatic ecosystems, and better judge how alien species interact with the ecosystems they invade.