Lake surfaces are warming worldwide, raising concerns about lake organism responses to thermal habitat changes. Species may cope with temperature increases by shifting their seasonality or their depth to track suitable thermal habitats, but these responses may be constrained by ecological interactions, life histories or limiting resources. Here we use 32 million temperature measurements from 139 lakes to quantify thermal habitat change (percentage of non-overlap) and assess how this change is exacerbated by potential habitat constraints. Long-term temperature change resulted in an average 6.2% non-overlap between thermal habitats in baseline (1978–1995) and recent (1996–2013) time periods, with non-overlap increasing to 19.4% on average when habitats were restricted by season and depth. Tropical lakes exhibited substantially higher thermal non-overlap compared with lakes at other latitudes. Lakes with high thermal habitat change coincided with those having numerous endemic species, suggesting that conservation actions should consider thermal habitat change to preserve lake biodiversity.

湖面正在全球变暖，引发了人们对湖泊生物对热栖息地变化的反应的担忧。物种可以通过改变它们的季节性或深度来追踪合适的热栖息地来应对温度升高，但这些反应可能受到生态相互作用、生活史或资源限制的限制。在这里，我们使用来自 139 个湖泊的 3200 万个温度测量值来量化热栖息地的变化（非重叠的百分比），并评估这种变化如何因潜在的栖息地限制而加剧。长期温度变化导致基线（1978-1995）和最近（1996-2013）时间段的热栖息地之间平均不重叠 6.2%，当栖息地受季节限制时，不重叠平均增加到 19.4%和深度。与其他纬度的湖泊相比，热带湖泊表现出更高的热不重叠。具有高热栖息地变化的湖泊与拥有众多特有物种的湖泊相吻合，这表明保护行动应考虑热栖息地变化以保护湖泊生物多样性。