Environmental warming induces behavioral and metabolic changes in a freshwater crustacean − aeglids as a model organism

Abstract

Ecological processes in small-order streams are dependent on their community. A threat to the appropriate functioning of these processes is the water warming of streams since changes in temperature can modify the behavior, abundance, and distribution of the species. A way to predict the consequences of global warming on ecological processes in these ecosystems is to study their aquatic community. Here we evaluated behavioral and metabolic changes in Aegla longirostri at different temperatures (21 °C and 24 °C). Experiments were performed in laboratory conditions. We calculated leaf consumption and quantified glycogen, protein and amino acid composition in the hepatopancreas. We also conducted a behavioral test to investigate the activity level of aeglids. Leaf consumption did not differ between temperatures. However, the amount of protein was higher at 21 °C, and the amino acid and glycogen levels were greater at 24 °C. In the present study we evaluated only the activity of hepatopancreas, so we can assume that the organ may have used glucose through the breakdown of glycogen and also performing some protein break. However, this hypothesis needs to be confirmed by checking for muscle activity. Animals kept at 24 °C showed a lower level of activity. This strategy possibly occurs to save energy, as in elevated temperature crustaceans spend extra energy to maintain their homeostasis. This study indicates that a future increase temperature of streams will impact the populations of aeglids by changing their metabolism and behavior.