Stock mapping, size structure and biological parameters of the clam Polititapes aureus in the shellfish production area of the southern Tunisian waters (Central Mediterranean)

Abdelkarim Derbali, Othman Jarboui

Paper category: Original research paper
Corresponding author: Abdelkarim Derbali (
DOI: 10.1515/ohs-2021-0012
Received: 27/10/2020
Accepted: 17/11/2020
Full text: here

Citation (APA style): Derbali,A. & Jarboui,O.(2021).Stock mapping, size structure and biological parameters of the clam Polititapes aureus in the shellfish production area of the southern Tunisian waters (Central Mediterranean). Oceanological and Hydrobiological Studies,50(2) 128-136.


The clam Polititapes aureus is one of the most abundant shellfish species in the southern Tunisian waters. Its current exploitation status and management are becoming a major concern for fishing industry in Tunisia. The significant ecological role of the species and possible future commercial benefits require a better knowledge of its stock. This research is the first attempt to investigate its current status in an area with the largest shellfish production. The obtained results showed a scattered distribution. The stock density ranged from 0 to 124 ind. m<sup>−2</sup>, and biomass values varied from 0 to 300 g m<sup>−2</sup>. This results in a remarkable biomass of 201.2 (± 64.6) t and high abundance reaching 91.3 ± 32.9 million individuals, estimated an area of 4182 ha. The species distribution was also investigated, with the size ranging from 4.9 to 35.34 mm. The overall sex ratio (F:M) was 1.26:1, which significantly deviated different from parity (1:1). The main environmental factors were identified and several abiotic parameters were found to strongly affect the spread of the clam species. The clam reproduce well and is expected to almost meet the domestic market demand through artisanal fishery.


This work was carried out as part of the research at the Laboratory of Fisheries Sciences of the National Institute of Marine Sciences and Technologies (INSTM). We wish to thank the anonymous reviewers for their suggestions and constructive comments, which helped to improve the quality of this manuscript.


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