Effects of temperature and hypoxia on aerobic scope in the giant freshwater shrimps (Macrobrachium rosenbergii) and (Penaeus monodon)

project summary

Depending on future CO2 emission scenarios, the average surface temperature is projected to increase 1.1-6.4°C by 2100. Tropical species, compared to many temperate species, are expected to be particularly sensitive to elevated temperatures because they inhabit a relatively thermostable environment and are thought to be genetically adapted to this stability. Recently, two papers in the prestigious journal Science have identified reduced aerobic scope as the most important physiological threat to population survival imposed by global warming, and several studies present evidence suggesting that this is already happening in a number of temperate fish species. However, there is presently very little evidence in tropical species. We propose to use respirometry (oxygen uptake) to measure aerobic scope at different temperatures and to combine these measurements with analysis of individual metabolites (Lactate, succinate, amino acids etc), as well as detailed information on growth rates and protein synthesis. The measurements will allow us to determine the temperature at which tropical crustaceans show reduced Darwinian fitness and to answer the important question of whether the predicted temperature increases will have a significant impact on these economically important shrimp species.