Food sources for camptandriid crabs in an arid mangrove ecosystem of the Persian Gulf: a stable isotope approach

ABSTRACT

Crabs of the family Camptandriidae are the most dominant burrowing crabs inhabiting arid mangrove forests of the Persian Gulf. They play important roles in the structuring and functioning of mangrove ecosystems by modulating biogeochemical processes and cycling of nutrients, serving as important ecosystem engineers. We analysed stable carbon (¹³C) and nitrogen (¹⁵N) isotope values of three camptandriid crabs (Opusia indica, Nasima dotilliformis, and Manningis arabicum) and their potential food sources in the Hara Biosphere Reserve, northern Persian Gulf. A Bayesian mixing model was used to estimate the contribution of potential food sources for consumers. The results showed that to some degree, all the four sources selected contributed to the camptandriid diets, but microphytobenthos made the most important contributions to the diet of the consumers. Mangroves do not appear to be a significant source of carbon in the diet of camptandriid crabs in the arid mangrove system of the Persian Gulf. Rather, they offer favourable growing conditions, thus boosting microphytobenthos production and availability for consumers which prefer a high nutritional and palatable source.

KEYWORDS:

• Carbon-13
• crabs
• diet effects
• ecosystem
• food
• isotope ecology
• nitrogen-15
• Persian Gulf

Acknowledgment

The authors wish to thank Nastaran Delfan, Parima Hajalizadeh, and many other students for the help with sample collections and Dr Reza Naderloo (University of Tehran) for the species identifications. We also thank Mohammad Reza Bartarang and Javad Mahmoodi for hospitality and logistical support during field sampling. The authors are grateful to Dr Behrooz Abtahi (Shahid Beheshti University) for his constructive comments and continuous encouragement. The stable isotope analyses were carried out at the LIENSs Stable Isotope Laboratory at the University of La Rochelle, France.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This research was supported by the Center for International Science Studies and Collaboration, Iran (CISSC) [grant number 484] and Iran National Science Foundation (INSF) [grant number 97000327], both of which are gratefully acknowledged.