Sources partitioning in the diet of the mudskipper Periophthalmus waltoni in an arid mangrove system: Evidence from stable isotope analysis

Abstract

Mudskippers (Gobiidae: Oxudercinae), are air-breathing fish, that play important roles in the structuring of benthic communities in mangrove habitats, serving as important ecosystem engineers. We used stable isotopes and the Bayesian mixing model to determine if mangrove provides a base of nutritional support to the mudskipper, Periophthalmus waltoni in the arid mangrove system of the Persian Gulf. The results showed that the species belong to the trophic level of the secondary consumers which mostly prey on species with the origin of the resources related to the mangroves. The mixing model results showed that all the three sources selected contributed to the species diets. Mangrove provided relatively high proportion (35.7%) of organic matter to the fish, followed by sediment organic matter (33.7%), and benthic microalgae (30.6%). The results highlight the fact that other features of food sources (i.e. quality, productivity) should be considered in addition to biomass when carrying out food web studies.