Apart from directly influencing individual life histories of species, climate change is altering key biotic interactions as well, causing community processes to unravel. With rising temperatures, disruptions to producer-consumer relationships can have major knock-on effects, particularly when the producer is a habitat-forming species. We studied how sea surface temperature (SST) modifies multiple pathways influencing the interaction between the foundational seagrass species, Posidonia oceanica, and its main consumer, the fish Sarpa salpa in the Mediterranean Sea. We used a combination of a field-based temperature gradient approaches and experimental manipulations to assess the effect of temperature on seagrass performance (growth) and fish early life history (larval development) as well as on the interaction itself (seagrass palatability and fish foraging activity). Within the range of temperatures assessed, S. salpa larvae grew slightly faster at warmer conditions but maintained their settlement size, resulting in a relatively small reduction in pelagic larval duration (PLD) and potentially reducing dispersion. Under warmer conditions (>24 °C), P. oceanica reduced its growth rate considerably and seemed to display fewer deterring mechanisms as indicated by a disproportionate consumption in choice experiments. However, our field-based observations along the temperature gradient showed no change in fish foraging time, or in other aspects of feeding behaviour. As oceans warm, our results indicate that, while S. salpa may show little change in early life history, its preference towards P. oceanica might increase, which, together with reduced seagrass growth, could considerably intensify the strength of herbivory. It is unclear if P. oceanica meadows can sustain such an intensification, but it will clearly add to the raft of pressures this threatened ecosystem already faces from global and local environmental change.

除了直接影响物种的个体生活史外，气候变化还改变着关键的生物相互作用，导致社区进程破裂。随着温度的升高，对生产者-消费者关系的破坏可能会产生重大的连锁反应，尤其是当生产者是形成栖息地的物种时。我们研究了海面温度（SST）如何修改影响基础海草物种Posidonia oceanica及其主要消费鱼Sarpa salpa之间相互作用的多种途径在地中海。我们结合使用基于现场的温度梯度方法和实验操作来评估温度对海草生长（生长）和鱼类早期生活史（幼虫发育）以及相互作用本身（海草适口性和鱼类觅食活动）的影响）。在评估的温度范围内，S。salpa幼虫在较温暖的条件下生长速度稍快，但保持其沉降大小，从而导致上层幼虫持续时间（PLD）的减少相对较小，并有可能减少扩散。下温暖的条件下（> 24℃），P.大洋洲降低了其生长速度，并且似乎显示出更少的威慑机制，如选择实验中不成比例的消耗所示。但是，我们沿温度梯度进行的野外观察表明，鱼类的觅食时间或摄食行为的其他方面没有变化。随着海洋变暖，我们的研究结果表明，尽管S.萨尔帕可能会出现在生命早期历史上变化不大，其对偏好P.大洋洲的可能增大，这与降低海草生长在一起，可大大加强取食的强度。尚不清楚海洋假单胞菌 草甸可以维持这种集约化生产，但显然将加剧该威胁生态系统已经面临的全球和本地环境变化带来的压力。