2018 Volume 23 Issue 2 Pages 199-221
River and coastal-basin habitats are affected by multiple factors that interact through complex processes. A comprehensive understanding of the relationships among these factors and processes as well as their impacts on target species is necessary for appropriate habitat management. While several studies have investigated factors that influence these relationships at the local level, no research has been conducted using national monitoring surveys, making it difficult to identify indicators of large-scale population dynamics. Here, we focused on shorebirds that have long been monitored in Japan, to determine which factors may affect these species. We first conducted a questionnaire survey among bird watchers to identify possible factors affecting shorebirds. We then conducted a questionnaire survey among researchers and connected the influential factors with large-scale drivers and impacts on shorebirds to draw the relationship diagram. Lastly, we conducted a literature review, which validated our results, as most of the relationships represented in our diagram have also been studied in other countries. However, previous studies in Japan have been limited and, therefore, further research, such as the development of indicators based on a national census, is needed to elucidate the relationships identified in this study.
