The Yangtze finless porpoise has become as significant indicator of current ecological conservation effectiveness in Poyang Lake, where nearly half of the population is found. Serious water shortages in the lake during the dry season has led the government to consider the establishment of a hydraulic project (PLHP) in order to remedy the deteriorating situation. However, the possible impacts of the PLHP on porpoise habitats is uncertain since the distribution of porpoise habitats during the dry season has not been sufficiently studied. Here, we combine hydrodynamic and species distribution models to simulate likely habitat and nursing area variations with or without PLHP during the dry season. Results indicate that flow velocity and distance to sand mining areas dominate the habitat preferences of the porpoise and its calves, respectively. Habitats were concentrated in the narrow channel of the Lake, which includes an area less than 10% of the lake inundation area. Under the operation of PLHP, the nursing area will increase, and the habitat will increase during September to December, but decrease during January to February. However, their proportion of the lake inundation area will decreased by 0.5% to 1.6%, and the distribution pattern will become more discontinuous. Our results suggest that the PLHP may not substantially benefit the porpoise, as it will block the only natural migration channel between Poyang Lake and the Yangtze River.

长江江豚已成为鄱阳湖生态保护成效的重要指标，鄱阳湖近半数的种群都在此栖息。旱季湖水严重短缺，导致政府考虑建立水利工程（PLHP）以补救不断恶化的情况。然而，PLHP 对江豚栖息地的可能影响尚不确定，因为旱季江豚栖息地的分布尚未得到充分研究。在这里，我们结合水动力和物种分布模型来模拟旱季期间有或没有 PLHP 的可能栖息地和护理区变化。结果表明，流速和到采砂区的距离分别支配着江豚及其幼崽的栖息地偏好。栖息地集中在湖泊狭窄的河道中，其面积不到湖泊淹没面积的10%。在PLHP的运行下，9-12月护理面积增加，栖息地增加，1-2月减少。但它们占湖泊淹没面积的比例将下降0.5%至1.6%，分布格局将更加不连续。我们的研究结果表明，PLHP 可能不会对江豚产生实质性的好处，因为它会阻塞鄱阳湖和长江之间唯一的天然迁徙通道。但在 1 月至 2 月期间减少。但它们占湖泊淹没面积的比例将下降0.5%至1.6%，分布格局将更加不连续。我们的研究结果表明，PLHP 可能不会对江豚产生实质性的好处，因为它会阻塞鄱阳湖和长江之间唯一的天然迁徙通道。但在 1 月至 2 月期间减少。但它们占湖泊淹没面积的比例将下降0.5%至1.6%，分布格局将更加不连续。我们的研究结果表明，PLHP 可能不会对江豚产生实质性的好处，因为它会阻塞鄱阳湖和长江之间唯一的天然迁徙通道。