Work

Historical and genetic perspectives on the spread of non-native bullheads, Ameiurus spp. (Actinopterygii: Ictaluridae), in Central Europe

Year: 2025

Type: article

Abstract: The genetic population structure and diversity of two invasive fish species in Central Europe, the brown bullhead (Ameiurus nebulosus) and the black bullhead (Ameiurus melas), were investigated. Using cytb mtDNA analysis, the brown bullhead exhibited a geographically dependent genetic structure, possibly reflecting an origin from two distinct sources. The first group included populations in the Czech Republic in the River Elbe and Danube basins, which could be related to the historical import of brown bullhead in the late 19th century. The second group consisted of populations from the River Oder, Vistula and Dniester basins in the Czech Republic and Ukraine. The mixed population in Poland indicates gene flow between these two groups, possibly associated with carp production and export. In contrast, the black bullhead showed minimum genetic differentiation across populations in Central Europe. Its low haplotype diversity and high interpopulation genetic similarity suggest a single introduction event in the Carpathian region, followed by successful dispersal. Our findings underscore the contrasting invasion histories and introduction pathways of these two related species. The brown bullhead's genetic variability reflects multiple, likely older introductions, resulting in a geographically structured population. Conversely, the black bullhead's genetic uniformity likely reflects a single introduction followed by the spread of a dominant haplogroup, suggesting a founder effect. This study provides valuable insights into how introduction history shapes the genetic patterns of invasive species, with implications for managing non-native fish populations in Central Europe.

Source: Folia Zoologica

DOI: 10.25225/jvb.25062