Genetic Diversity and Conservation of the Prespa Trout in the Balkans

Abstract

The Balkans are known to have a high level of biodiversity and endemism. No less than 15 taxa have been recorded in salmonids of the Salmo genus. Among them, the Prespa trout is found in only four river systems flowing into Lake Macro Prespa, three in the Former Yugoslav Republic of Macedonia and one in Greece. This is the first comprehensive survey of all streams located within the Macro Prespa Basin, encompassing the whole taxon range. A large genetic sample of 536 Prespa trout was collected mainly between 2005 and 2007. The sampling included 59 individuals from the Golema river system, 93 from the Kranska, 260 from the Brajcinska, 119 from the Agios Germanos, and five individuals from the lake itself. These specimens were analyzed with six microsatellite markers and by sequencing the mitochondrial control region. Nuclear data were examined through multidimensional analysis and assignment tests. Five clusters were detected by assignment: Golema, Kranska, Brajcinska upstream, Rzanska Brajcinska tributary and Brajcinska downstream. Most of these river systems thus hosted differentiated Prespa trout populations (with past gene flows likely dating before the construction of dams), except Agios Germanos, which was found to be composed of 5% to 32% of each cluster. Among the five trout individuals from the lake, four originated from Kranska River and one was admixed. Supported parsimonious hypotheses are proposed to explain these specificities. Conservation of this endemic taxon should take these results into account. No translocation should be performed between different tributaries of the lake and preservation of the Brajcinska populations should address the upstream-downstream differentiation described.

Temporal changes in allele frequencies in a small marble trout Salmo marmoratus population threatened by extreme flood events

“…trutta (Pujolar et al , ). Similar heterozygosities ( H O = 0·16–0·35) have been observed in the Prespa trout Salmo peristericus Karaman 1938 in Macedonia (Berrebi et al , ), another endangered salmonid as a result of anthropogenic factors including reintroductions. The low heterozygosities found in the threatened S .…”

“…While Italian S. marmoratus populations are not experiencing floods, they are subjected to the negative effect of introgression with S. trutta (Pujolar et al, 2011a). Similar heterozygosities (H O = 0⋅16-0⋅35) have been observed in the Prespa trout Salmo peristericus Karaman 1938 in Macedonia (Berrebi et al, 2013), another endangered salmonid as a result of anthropogenic factors including reintroductions. The low heterozygosities found in the threatened S. peristericus and S. marmoratus (this study) contrast with the microsatellite heterozygosity values generally found in salmonids, ranging between 0⋅6 and 0⋅8 (Hansen et al, 2002;Jensen et al, 2005;Serbezov et al, 2008).…”

Investigating the genetic structure of trout from the Garden of Ninfa (central Italy): Suggestions for conservation and management

“…Berrebi et al, 2013;Gratton, Allegrucci, Sbordoni & Gandolfi, 2014;Maric, Bajec, Schoffmann, Kostov & Snoj, 2017 and references therein). Berrebi et al, 2013;Gratton, Allegrucci, Sbordoni & Gandolfi, 2014;Maric, Bajec, Schoffmann, Kostov & Snoj, 2017 and references therein).…”

Brown trout (Salmo trutta L.) high genetic diversity around the Tyrrhenian Sea as revealed by nuclear and mitochondrial markers

“…probably have a trans-Apennine origin due to their genetic similarity with haplotype ADcs11 (see Fig. 2), 346 this latter being very common in the Adriatic region Berrebi et al, 2013). 347 diversity of more western origin (AD-Tyrrh1, 2 and 4).…”