Rising sea surface temperatures affect the feeding behaviour and reproductive success of many coastal benthic invertebrates. This experimental study investigated the effects of ocean warming on macroalgal food consumption rates in the sea urchins Arbacia lixula and Paracentrotus lividus from Madeira Island to assess how the feeding pressure they exert may change under warmer ocean conditions. Additionally, in A. lixula, the relationship between temperature and the gonad index was examined to estimate potential future reproductive output. Over the course of 25 days, 180 individuals of each species were exposed to temperatures between 22 °C and 31 °C. After 20 days, consumption rates were assessed in 48-h feeding trials. Gonad indices of A. lixula were determined on the last day of the experiment. In the thermal range investigated, both traits were found to be unimodal functions of temperature. In addition to temperature, consumption rates in both species and the gonad indices in A. lixula were influenced by body size, while feeding in A. lixula also varied between sexes. Maximum food consumption rates (A. lixula and P. lividus) as well as maximum gonad indices (only A. lixula) were observed between 25 °C and 26 °C. These values are at the upper end of the temperature range that currently prevails around Madeira, and may become average summer temperatures by the year 2100. Consequently, both sea urchin species may thrive during future warm summers and may enhance their top-down control on local macroalgal populations.

海面温度上升影响许多沿海底栖无脊椎动物的摄食行为和繁殖成功。这项实验研究调查了海洋变暖对来自马德拉岛的海胆Arbacia lixula和Paracentrotus lividus 的大型藻类食物消耗率的影响，以评估它们施加的摄食压力在温暖的海洋条件下可能如何变化。此外，在A. lixula 中，检查了温度与性腺指数之间的关系，以估计潜在的未来生殖输出。在 25 天的过程中，每个物种的 180 只个体暴露在 22°C 到 31°C 之间的温度下。20 天后，在 48 小时喂养试验中评估消耗率。A. lixula的性腺指数在实验的最后一天确定。在研究的热范围内，发现这两个特性都是温度的单峰函数。除了温度之外，A. lixula 的两个物种的消耗率和性腺指数都受到体型的影响，而A. lixula 的摄食也因性别而异。最大食物消耗率（A. lixula和P. lividus）以及最大性腺指数（仅A. lixula) 在 25 °C 和 26 °C 之间观察到。这些值处于马德拉岛目前普遍存在的温度范围的上限，到 2100 年可能会达到夏季平均温度。 因此，这两种海胆物种可能会在未来温暖的夏季茁壮成长，并可能加强它们对当地自上而下的控制大型藻类种群。