First record of Sebastes schlegelii Hilgendorf, 1880 along the Turkish Black Sea coast – new addition to the alien species inventory

Abstract

Sebastes schlegelii is a typical bottom dwelling boreal species, whose native distribution range includes Japan, Korean peninsula and China. This northwest Pacific originated species has recently been recorded from the Crimean and Caucasian coast (northern Black Sea), whose introduction was assumed to be either by balast waters or the acclimatization of Crassostrea gigas (Pacific oyster). On 16 August 2023, a single S. schlegelii specimen with 20.6 cm standard length and 282.1 g in weight was captured off Ünye, Ordu coast (southeastern Black Sea), which was previously an unreported fish from the Turkish marine waters. Detailed morphometric and meristic characteristics are presented in the paper, and species identification was further confirmed by genetic analysis. Available information reveals this alien species to be fished regularly, although in small quantities, indicating a presumably established population in the region. The species should be treated as a potentially invasive fish, since it may negatively influence to the local biodiversity through interspecific competition. Close monitoring of its existing population is strongly suggested.