Range extension of the Asian green mussel Perna viridis (Linnaeus, 1758) into a Marine Extractive Reserve in Brazil

Abstract

Biological invasions can cause significant changes in the abundance and distribution of species in recipient communities. The effect of invasive species on native biota is now one of the most addressed topics in studies of biological invasions. On March 20, 2022 two juvenile individuals of a never-before-seen mussel were detected on a mussel farm during cleaning activities in the Arraial do Cabo Marine Extractive Reserve (MER), Brazil. The brilliant green color of the margin of the predominantly brown shell was the initial characteristic used to identify the specimens as the Asian green mussel Perna viridis. Biometric features of both the farmed mussel Perna perna and P. viridis were compared to estimate age, and photographs were taken of the anatomical structures. Similar ages of mussel species in farm lanterns suggested that P. viridis may have been present, but overlooked, on nearby shores during spat collection, though no mature individuals were seen. Alternatively, marine farms may be more susceptible to invasion by other bivalves, as has been reported at other locations. This third record in the southwest Atlantic (Brazil) extends the range by 110 km eastward from the first report four years previously. With a port and harbor nearby, the most probable vector of introduction to the region was fouling on small boats. We fully expect P. viridis to continue its range expansion along the southwest Atlantic coastline. MERs provide a model of ecosystem and resource management which combine sustainable development and the conservation of natural resources to benefit artisanal fishers and other stakeholders. It is therefore important to establish long-term programs for monitoring, prevention and control of biological invasions at MERs, especially at Arraial do Cabo, which seems to be an invasion hotspot and, by its very nature, is particularly sensitive to marine biological invasions.