A global review of patterns of aquatic macroinvertebrate dispersal and functional feeding traits in aridland rock pools

Authors: Susan Washko, Michael Bogan

Year: 2019

Abstract

Rock pools are important ecosystems providing rare sources of surface water in arid regions. Hydroperiod is one of the primary limiting factors for aquatic macroinvertebrates living in rock pools. Resident macroinvertebrates must complete their life cycles before pool drying, and may employ active or passive dispersal strategies to survive. Quantifying dispersal and functional feeding traits across rock pool macroinvertebrate communities in multiple regions could provide insight into how rock pool ecosystems will respond to shorter hydroperiods predicted by climate change models. We reviewed taxonomic data (26 species lists) from 24 published studies on rock pools in Africa, North America, and Australia, to assess the dispersal and feeding strategies of macroinvertebrates, and how ecosystem functions may change with shorter hydroperiods. On average, taxa lists were equally comprised of active dispersers and passive dispersers. Most active disperser taxa were predators (60%) and gatherers (33%). In contrast, passive disperser taxa were generally filterers (39%), gatherers (29%), and scrapers (21%). Climate change may reduce rock pool hydroperiods, which could reduce habitat availability for passive dispersers with weak overland dispersal abilities. If passive disperser populations decrease, their associated ecosystem functions, such as fine organic matter processing, could be disrupted. These results provide a foundation for future work investigating changes in rock pool ecosystem function due to altered hydroperiods.