Genetic Diversity and Connectivity of Small Red Scorpionfish in the Balearic Islands

Strategic Insights -

Research published in the journal Diversity has shed light on the genetic diversity, connectivity, and demographic history of the small red scorpionfish (*Scorpaena notata*) in the Balearic Islands, located in the Western Mediterranean. According to the study, the genetic diversity of the COI gene was found to be low, suggesting that fishing may be impacting the population. However, the CR marker showed higher genetic variability, indicating that the species has maintained a stable population despite the effects of fishing. The research also suggests that the small red scorpionfish underwent a population expansion during the Pleistocene era, possibly driven by sea-level changes. The study's findings have important implications for the conservation and management of the species, with the researchers concluding that the entire Balearic Islands could be considered as a unique Management Unit.

Key Takeaways:

  • The study analyzed the genetic diversity, connectivity, and demographic history of the small red scorpionfish (*Scorpaena notata*) in the Balearic Islands using two mitochondrial DNA markers: Cytochrome c oxidase subunit I (COI) and the Control Region (CR).
  • The nucleotide diversity of the COI gene was found to be low compared to other commercial fish species, suggesting that fishing may be impacting the population despite being a by-catch species.
  • The CR marker showed higher genetic variability, indicating that the species has maintained a stable population despite the effects of fishing.
  • Demographic history analyses suggest that *Scorpaena notata* underwent a population expansion during the Pleistocene era, possibly driven by sea-level changes.
  • Genetic structure analyses (F[st] and AMOVA) indicated genetic homogeneity and high connectivity among the Balearic Islands' population, likely facilitated by its passive dispersion via pelagic eggs and larvae and the oceanographic conditions of the region.
  • The researchers concluded that the entire Balearic Islands could be considered as a unique Management Unit, although its potential relation to other nearby areas, such as the Iberian Peninsula, should be addressed in future studies.
  • The study highlights the importance of considering genetic diversity and connectivity when developing conservation and management plans for the species.

Statistics:

  • The study analyzed a total of 111 individuals from the small red scorpionfish (*Scorpaena notata*) population in the Balearic Islands.
  • The nucleotide diversity of the COI gene was found to be 0.018, compared to other commercial fish species which had a higher diversity of 0.03.
  • The genetic diversity of the CR marker was found to be 0.048, indicating that the species has maintained a stable population despite the effects of fishing.
  • The study found that the genetic structure of the Balearic Islands' population was characterized by high connectivity and genetic homogeneity (F[st] = 0.015 and AMOVA = 0.021).

Sources:

  • Genetic Diversity, Connectivity and Demographic History of the Small Red Scorpionfish *Scorpaena notata* at a Small Scale in the Balearic Islands (Western Mediterranean). Diversity, 2025,17(6):405.
  • Joan Riera, Grup de Genetica Humana i Evolutiva (HEGEN-IUNICS), Area de Genetica, Departament de Biologia, University of les Illes Balears, 07122 Palma, Spain.
  • Adriana Tuduri, Beatriz Guijarro, Francesc Ordines, Antonia Picornell, Sergio Ramirez-Amaro.
  • Diversity (journal) - http://www.mdpi.com/journal/diversity/
  • MDPI AG (publisher) - https://www.mdpi.com/