Assessment of Ostrea stentina recruitment and performance in the Mar Menor lagoon (SE Spain)

The Mar Menor is a hypersaline coastal lagoon representing one of the most iconic natural areas in Southeastern Spain. However, it has suffered several catastrophic environmental events causing an exceptional eutrophication status. A study was performed to assess the recruitment of oysters in the Mar Menor, determine their taxonomic allocation and evaluate functionality in filtration and growth A total of 45 spat collectors were installed in June 2020 and posteriorly retrieved in October 2020. In total, 3431 oyster recruits were counted. Two species of oyster Ostrea edulis and O. stentina, inhabit the Mar Menor, but they are indistinguishable at the morphological level when they are small. Thus, a genetic tool was developed to identify both species. From a total of 90 oyster recruits, 95% of them corresponded to O. stentina. Finally, growth rate and clearance measurements were conducted on 661 oysters over 6 months under laboratory conditions to explore their possible use in the bioremediation of the lagoon.

We appreciate the work done by F. Gomez in the maintenance and feeding of the oyster spat, the collaboration of the students D. Lorente and P. Poveda from the Secondary School IES Ruiz de Alda (San Javier, Murcia), in the physiological determinations, and the technical assistance of Susana Sánchez for genetic analyses. This research has been performed in the scope of the LIFE IP INTEMARES project, coordinated by the Biodiversity Foundation of the Ministry for the Ecological Transition and the Demographic Challenge. It receives financial support from the European Union’s LIFE programme (LIFE15 IPE ES 012). MVL was supported by a postdoctoral contract Juan de la Cierva-Incorporación, Spain (IJCI-2016-29329) of Ministerio de Ciencia, Innovación Universidades. Genetic analyses have been financed by the General Direction of the Mar Menor from the Murcia Regional Government, Spain .

Peer reviewed