Muhawenimana V, Thomas J R, Wilson C A M E, Nefjodova J, Chapman A C, Williams F C, Davies D G, Griffiths S W, Cable J
School of Engineering, Cardiff University, Cardiff CF10 3AA, UK.
School of Biosciences, Cardiff University, Cardiff CF10 3AX, UK.
R Soc Open Sci. 2021 Feb 24;8(2):201516. doi: 10.1098/rsos.201516.
Global climate change continues to impact fish habitat quality and biodiversity, especially in regard to the dynamics of invasive non-native species. Using individual aquaria and an open channel flume, this study evaluated the effects of water temperature, flow velocity and turbulence interactions on swimming performance of two lentic, invasive non-native fish in the UK, pumpkinseed () and topmouth gudgeon (). Burst and sustained swimming tests were conducted at 15, 20 and 25°C. Acoustic Doppler velocimetry was used to measure the flume hydrodynamic flow characteristics. Both and occupied the near-bed regions of the flume, conserving energy and seeking refuge in the low mean velocities flow areas despite the relatively elevated turbulent fluctuations, a behaviour which depended on temperature. Burst swimming performance and sustained swimming increased by up to 53% as temperature increased from 15 to 20°C and 71% between 15 and 25°C. Furthermore, fish test area occupancy was dependent on thermal conditions, as well as on time-averaged velocities and turbulent fluctuations. This study suggests that invasive species can benefit from the raised temperatures predicted under climate change forecasts by improving swimming performance in flowing water potentially facilitating their further dispersal and subsequent establishment in lotic environments.
全球气候变化持续影响鱼类栖息地质量和生物多样性，尤其是在入侵非本地物种的动态方面。本研究使用个体水族箱和明渠水槽，评估了水温、流速和湍流相互作用对英国两种静水入侵非本地鱼类——蓝鳃太阳鱼（Lepomis gibbosus）和麦穗鱼（Pseudorasbora parva）游泳性能的影响。在15、20和25°C下进行了爆发式和持续游泳测试。使用声学多普勒测速仪测量水槽的水动力流动特性。蓝鳃太阳鱼和麦穗鱼都占据了水槽的近床区域，尽管湍流波动相对较高，但它们在低平均流速区域保存能量并寻求庇护，这种行为取决于温度。随着温度从15°C升高到20°C，爆发式游泳性能和持续游泳能力提高了53%，在15°C至25°C之间提高了71%。此外，鱼类测试区域的占有率取决于热条件，以及时间平均流速和湍流波动。本研究表明，入侵物种可以受益于气候变化预测中预计的温度升高，通过提高在流动水中的游泳性能，这可能有助于它们在 lotic 环境中进一步扩散和随后的定居。
