High genetic diversity in an invasive freshwater fish species, Carassius gibelio, suggests establishment success at the frontier between native and invasive ranges

Abstract

Non-native freshwater fish introductions can have direct and indirect negative effects on native flora and fauna, ecosystems, and national economies. Although invasions are paradoxical from an evolutionary standpoint, population genetics could be useful to understand invasion scenarios of non-native species. One of the most common introduced fish in Europe and Turkey is the gibel carp Carassius gibelio, which was first introduced from East Asia in the 17th century. To find out the origin and distribution pattern and characterise the genetic variation of gibel carp in Turkey, the aim of this study was to identify haplotype the species' diversity and distribution in the country. Three mitochondrial (COI, Cyt-b and D-loop) and one nuclear (ITS1) DNA markers were used in 20 populations sampled from 18 different geographic locations, resulting in eight newly-identified haplotypes. The present results: (i) suggest high genetic diversity across regions at both the mitochondrial (29 haplotypes, h = 0.9058, pi = 0.0152) and nuclear (3 haplotypes, h = 0.6365, pi = 0.0094) level; (ii) confirm previous findings that this species may have entered Turkey directly either from its native or through its invasive range; (iii) suggest that, given the distribution of the identified haplotypes by geographic location, the majority of individuals not only originated from the northern (European) part of Turkey but also from the southern (Mediterranean) part of the country. Understanding the genetic characterisation of gibel carp can contribute to more efficient management actions for this species, including prevention of (multiple) introductions and eradication/control of those populations with relatively low genetic diversity. (C) 2019 Elsevier GmbH. All rights reserved.