Lake Baikal amphipods under climate change: thermal constraints and ecological consequences

Lake Baikal, the world's deepest and most voluminous freshwater lake, is experiencing rapid warming, which poses significant thermal constraints on its unique amphipod fauna. This study identified species-specific thermal tolerance limits in two endemic Baikal amphipods (Eulimnogammarus verrucosus and E. cyaneus) and a non-endemic Holarctic species (Gammarus lacustris). Using the oxygen- and capacity-limited thermal tolerance (OCLTT) framework, researchers found that E. verrucosus retreats from upper littoral zones once its pejus temperature (Tp) of 10.6°C is surpassed, marking a critical ecological boundary. While G. lacustris shares similar upper thermal limits with E. cyaneus, rising temperatures may not necessarily benefit the non-endemic species as previously thought. The study highlights the importance of behavioral plasticity in endemic species and suggests that secondary effects of warming require further investigation.

Jakob, L., Axenov‐Gribanov, D. V., Gurkov, A. N., Ginzburg, M., Bedulina, D. S., Timofeyev, M. A., Luckenbach, T., Lucassen, M., Sartoris, F. J., & Pörtner, H.-O. (2016). Lake Baikal amphipods under climate change: thermal constraints and ecological consequences. Ecosphere, 7(3). Portico. https://doi.org/10.1002/ecs2.1308