Sand Prawns Mitigate the Impact of Prolonged Drought on the Biology of a Temporary Open/Closed Estuary

Le résumé fourni par la source

The role of the sand prawn, Callichirus kraussi (Stebbing, 1900), as an ecosystem engineer was evaluated using a three-month-long caging experiment during a prolonged drought in the lower reaches of the temporarily open/closed Kasouga Estuary along the eastern seaboard of South Af-rica. The current study indicates that at intermediate densities, the burrowing activities of the sand prawn contributed to a significant increase in the microphytobenthic algal concentrations and a concurrent increase in the abundance and biomass of the macrofauna (P < 0.05 in all cases). The increase in macrofauna abundance and biomass could largely be ascribed to the elevated densities of the gastropod, Nassarius kraussianus which were sustained by the elevated microphytobenthic biomass. As such, the sand prawn Callichirus kraussi was established to be an important ecosystem engineer as the results indicate that intermediate densities of the sand prawn may locally con-tribute to increases in the biology even during those periods when the system is stressed, in this case, the prolonged drought.

Ce résumé expose les affirmations des auteurs. BNTIC ne l’interprète pas comme une validation indépendante des résultats.