Community assembly of adult odonates in lacustrine systems of an understudied world heritage site of south-eastern Zimbabwe

Abstract

Odonata (dragonflies and damselflies) are efficacious for management and conservation efforts in freshwaters. In recent times, increased effort has gone into enhancing awareness, data and information on dragonflies among scientists and policymakers. Here, we examined the Odonata community of dams within the Matobo National Park, a world heritage site in southern Zimbabwe. Specifically, we determined diversity of larval and adult odonate in five dams over one year. Several physico-chemical parameters were measured, including pH, total dissolved salts (TDS), electrical conductivity (EC). Further, we assessed how habitat types (i.e., detritus, sand, gravel, plant type) affect Odonata communities. In addition, surveys were conducted to identify critical threats to Odonata in the Matobo National Park and surrounding areas. Broadly, results showed that Odonata nymphs and volant adults did not change predictably across all sampling occasions. Further, pH was positively correlated with Libellulidae and Platycnemididae, whereas TDS and EC were positively correlated with Libellulidae, Platycnemididae and Macromiidae. Contrariwise, Gomphidae were found to be negatively correlated to TDS, EC and pH. The threat analyses identified natural system modifications, agricultural expansion and intensification, as well as human intrusions and disturbance as the major threats to Odonata and freshwater resources in Matobo National Park. Taken together, these data provide baseline data that will be useful for future monitoring of threats and subsequently conservation strategies in the Matobo National Park and other protected areas in Southern Africa.