Parasites of Sardinella maderensis (Lowe, 1838) (Actinopterygii: Clupeidae) and Their Potential as Biological Tags for Stock Identification along the Coast of West Africa

SIMPLE SUMMARY: Sardinella maderensis, representing one of the most commercially important small pelagic fish species along the coast of West Africa, is suffering a drastic decline as a result of overfishing, the overcapacity of fishing fleets, the destruction of fish habitat, the use of inappropriate fishing gears and techniques, as well as environmental changes. The limited reliable information on their stock for sustainable management constitutes one of the problems facing small pelagic fish in general and Sardinella maderensis particularly along the coast of West Africa. The key goals of this study were to identify the parasites of Sardinella maderensis and to assess their potential use as biological tags for stock identification along the coast of West Africa (Benin and Ghana). The objectives of this study were to determine the morphological parameters (total length and body weight) of S. maderensis, identify their parasites in Benin and Ghana and select appropriate parasites with potential to be used as biological tags. The results suggest that the nematode Anisakis sp(p). and the cestode Tentacularia coryphaenae may serve as potential biological tags for the stock identification of Sardinella maderensis. ABSTRACT: This study is the first to provide information on the parasite fauna of Sardinella maderensis along the coasts of Benin and Ghana, and the first to investigate the potential use of parasites as biological tags in fish population studies in the area. It may thus serve as a starting point for upcoming studies. From February to June 2021, a total of 200 S. maderensis were sampled from the fishing port of Cotonou (Benin) and the Elmina landing site (Ghana). The prevalence and abundance of each parasite were recorded. The following are the outcomes of this study: Parasite species, such as Parahemiurus merus, Mazocraeoides sp. and Hysterothylacium fortalezae, were recorded along the coasts of Benin and Ghana, while Anisakis sp(p). and Tentacularia coryphaenae were only recorded along the coast of Benin. Parahemiurus merus was the most prevalent and abundant among all the parasites recorded. Anisakis sp(p). and T. coryphaenae were selected as having potential in the stock identification of S. maderensis. Both parasites were only recorded along the coast of Benin at a low prevalence. As a result, examinations of more S. maderensis from each location for these parasites may justify their use in stock identification studies.