Troia Matthew J, Perkin Joshuah S
Department of Integrative Biology, University of Texas at San Antonio, San Antonio, TX 78249, USA.
Department of Ecology and Conservation Biology, Texas A&M University, College Station, TX 77843, USA.
Conserv Physiol. 2022 Jul 2;10(1):coac035. doi: 10.1093/conphys/coac035. eCollection 2022.
Rising water temperature under climate change is affecting the physiology, population dynamics and geographic distribution of freshwater taxa. We propose a novel application of individual-based bioenergetics modelling (BEM) to assess the physiological impacts of warming on freshwater fishes across broad spatial extents. We test this approach using the Guadalupe bass (), a species of conservation and recreational significance that is endemic to central TX, USA. We projected historical-to-future changes (middle 20th century to end of 21st century) in daily bioenergetics of individual fish across 7872 stream reaches and compared this output to changes in reach occupancy derived from traditional species distribution modelling (SDM). SDMs project an 8.7% to 52.1% decrease in reach occupancy, depending on model parameterizations and climate change scenarios. Persistence is projected in the central Edwards Plateau region, whereas extirpations are projected for the warmer southeastern region. BEM projected a median 79.3% and 143.2% increase in somatic growth of age-1 Guadalupe bass across historically occupied reaches under moderate and severe climate change scenarios, respectively. Higher end-of-year body size under future climate was caused by a longer growing season. Future scenarios exploring suppressed or enhanced prey consumption suggest that small changes in prey availability will have relatively greater effects on growth than forecasted changes in temperature. Projected growth was geographically discordant with SDM-based habitat suitability, suggesting that SDMs do not accurately reflect fundamental thermal niche dimensions. Our assessment suggests that for locations where the species persists, Guadalupe bass may benefit from warming, although realized consumption gains will depend on seasonal, spatially varying changes in prey availability and other biotic and abiotic factors. More generally, we demonstrate that uniting species-specific BEM with spatially explicit climate change projections can elucidate the physiological impacts of climate change-including seasonal variation-on freshwater fishes across broad geographic extents to complement traditional SDM.
气候变化导致的水温上升正在影响淡水生物分类群的生理机能、种群动态和地理分布。我们提出一种基于个体的生物能量学建模（BEM）的新应用，以评估变暖对广泛空间范围内淡水鱼类的生理影响。我们使用瓜达卢佩鲈（）对这种方法进行测试，该物种在美国得克萨斯州中部特有的具有保护和休闲意义。我们预测了7872条溪流中个体鱼类每日生物能量学从历史到未来（20世纪中叶到21世纪末）的变化，并将此输出结果与传统物种分布模型（SDM）得出的河段占用变化进行比较。根据模型参数设置和气候变化情景，SDM预测河段占用率将下降8.7%至52.1%。预计爱德华兹高原中部地区该物种将持续存在，而较温暖的东南部地区预计将灭绝。BEM预测，在中度和重度气候变化情景下，历史上有该物种生存的河段中，1龄瓜达卢佩鲈的体细胞生长中位数分别增加79.3%和143.2%。未来气候条件下年末体型更大是由于生长季节延长。探索猎物消耗受到抑制或增强的未来情景表明，猎物可获得性的微小变化对生长的影响将比预测的温度变化更大。预测的生长情况在地理上与基于SDM的栖息地适宜性不一致，这表明SDM不能准确反映基本的热生态位维度。我们的评估表明，对于该物种持续存在的地点，瓜达卢佩鲈可能会从变暖中受益，尽管实际的消耗增加将取决于猎物可获得性以及其他生物和非生物因素的季节性、空间变化。更普遍地说，我们证明将特定物种的BEM与空间明确的气候变化预测相结合，可以阐明气候变化（包括季节变化）对广泛地理范围内淡水鱼类的生理影响，以补充传统的SDM。
