Identifying, preventing and mitigating ecological traps to improve the management of urban aquatic ecosystems.
Abstract
Urbanization alters the environmental characteristics of aquatic ecosystems, often reducing the availability and quality of habitats for animals. Improving the condition of urban waterbodies is increasingly important, but management activities could have unintended outcomes that increase the extinction risk for animals. A mismatch can exist between human perceptions of habitat quality, and what represents functional habitats for animals. This can lead to animals not responding to management activities, if presumed high-quality habitats are unsuitable. More seriously, the fitness of animals could be compromised by management activities, especially if animals prefer threatening habitats resulting in an ecological trap. Ecological traps can drive populations to extinction and may arise directly from management activities. However, there has been limited work on how to best manage traps despite their important implications for the conservation and management of animal populations. We illustrate how urban management activities could cause ecological traps, and potential ways that traps could be managed. We outline a decision framework to identify, prevent and mitigate ecological traps, and illustrate this framework using stormwater wetlands as a case study. Stormwater wetlands have many features of natural wetlands but accumulate pollutants as part of the stormwater treatment process and there is a high likelihood some are traps. If so, this will be an important environmental issue, given the rate at which these wetlands are being created around many cities. Synthesis and application. Ecological traps that arise as unintended outcomes of management activities could represent a serious but currently underappreciated environmental problem. Our study will help minimize the risk that management activities inadvertently decouple habitat selection cues from habitat quality, and mitigate the potential consequences for animals when this does occur. This is an important step to ensure that management activities achieve desired ecological outcomes and do not result in unintentional environmental degradation.