Gate operation for habitat-oriented water management at Budai Salt Pan Wetland in Taiwan

Abstract

Commercial salt pans around the world act as important habitats for waterbirds due to their unique trophic and physical attributes. Today, most commercial salt pans in Taiwan have been decommissioned and many have been designated as protected wetland habitats. Due to the dike and water gate systems controlling water flow in the salt pan wetlands, water management plans are important for habitat maintenance. Despite this, creation and implementation of habitat-oriented water management plans in protected salt pan wetlands is not common practice, especially in areas where flooding is a concern. In order to understand the potential for implementing water management plans for habitat creation in salt pan wetlands located in flood prone regions, this study designed and conducted three water management experiments for Budai Salt Pan Wetland, a wetland of national importance along the southwestern coast of Taiwan. The three experiments were designed to better understand the impacts of allowing water into the wetland during both the end and the beginning of the dry season in Taiwan. The design of each water gate operation was unique, based on the initial hydrologic conditions, and needs of the experiment in order to inform the design of future water management plans for the wetland. The consequent influence of gate operations on water depth, salinity, and immediate bird use of the wetland were analyzed. The experiments show that the water management techniques adopted in the study can allow for the creation of habitat types with varying water depths and salinity while not increasing flood risk to surrounding communities. Because the gate operation experiments were short term, a complete understanding of bird responses was limited. Even so, the responses of waterbird communities to these depth manipulations did indicate the potential of water management to increase foraging opportunities. The methods and findings of this research can inform wetland management and policy throughout Taiwan and the rest of the world.