A comparison of Cladocera and Copepoda as indicators of hydroperiod length in Mediterranean ponds

Yearly variation in water availability patterns has a remarkable effect in the presence of freshwater microcrustacean species. We hypothesize that, based on their different reproductive strategies, Cladocera and Copepoda may show differences in their association with ponds of different hydroperiods, i.e. in their indicator value. In order to test our hypothesis, cladoceran and copepod assemblages from ponds in Mediterranean woodlands in Latium (Italy) were analysed to evaluate their role as indicators of ponds attributed to four hydroperiod categories. Twenty-five cladocerans and sixteen copepods were collected. Correspondence analysis performed on the copepod species matrix clearly arranged the sites along a hydroperiod gradient; conversely, the same analysis carried out on cladocerans failed to distinguish between the hydroperiod categories. An indicator species analysis confirmed that copepods have a higher fidelity to the target site group. The high ability of copepods in discriminating ponds with different wet phase durations suggests their use as indicators of hydroperiod variation due to land use and climate change.