Oral Presentation International Conference on River Connectivity (Fish Passage 2018)

Developing a theoretical model to help design ecologically-friendly fishway of the endangered fish species, scale-less carp (Gymnocypris przewalskii) in the Qinghai Lake watershed, western China (#82)

Mengzhen Xu 1 , Chendi Zhang 1 , Giri Kattel 2 , Zhongjing Wang 1
  1. Tsinghua University, Beijing, BEIJING, China
  2. Department of Infrastructure Engineering, University of Melbourne, Victoria, Australia

The scale-less carp (Gymnocypris przewalskii) is an endangered and a unique highland cyprinid fish has long history of ecological values in northwest China. The fish migrates annually between the alkaline water Qinghai Lake and the freshwater tributaries in the region, where it feeds, grows and spawns. However, due to climate change and human disturbances, such as construction of barrages or diversion channels, its migration pathways have been impaired severely. Massive numbers of spawning fish are found exhausted and died when trying to cross the barriers due to their heights and disruptions made on the hydraulic conditions. Efforts are being made for improved fishway designs to restore the migratory routes of this species. However, the actual effectiveness and suitability of such fishways are not assessed comprehensively. This study aims to evaluate a range of ecological demands of this species and characterize the features of its preferred natural migration routes, so that it would help design the most ecologically friendly fishways in the Qinghai plateau region imitating the natural step-pool type system. We will work closely with local conservation authority to meet their conservation efforts through field investigation, theoretical modeling, laboratory tests and field experiments. Primarily, natural conditions of the preferred migration routes are measured in the field during the migration season. For this, a model is built to study the adaptability of the species to the physical and chemical parameters of the migration route. Secondly, laboratory tests will be performed to study the migratory behavior and response to the hydrodynamic conditions of the species. The key elements needed for the step-pool system fishways design will then be determined according to the results of field investigation and laboratory experiments.