Phylogeographic Identification of Tench Tinca tinca (L.1758) (Actinopterygii: Cyprinidae) from the Northern Balkans and Adjacent Regions and itsImplications for Conservation

摘要

The tench, , is anendangered freshwater fish species in the Balkans. However, there are no management andconservation strategies developed for this species so far. In order to be able to developsuch strategies, we first determined the phylogeographic identity of 70 tench individualsfrom four countries (Serbia, FYRO Macedonia, Hungary and Croatia) by PCR-RFLP analyses oftwo nuclear markers ( and ) and one mitochondrialmarker ( ). All makers enabled the identification of two majorgeographic clades of tench (Western and Eastern), while nuclear markers additionallyenabled the identification of hybrids between the two clades. Based on the mitochondrialmarker , tench populations can be separated into two distinct areas:areas north of the Danube River with the dominant Western origin, and areas south of theDanube River with the dominant Eastern origin. Data obtained for the gene demonstrated Eastern origin for most individuals (88.23%) while dataobtained for the gene demonstrated mixed origin with a highpercentage of hybrids. The presence of high numbers of individuals with Western allelesfor the gene in areas south of the Danube may indicate a naturalinvasion of this phylogroup. According to these results, areas north and south of theDanube are identified as two main management units. Additionally, we identified the rarewestern haplotype W2 based on the marker which clearly indicatedhuman-aided dispersals of tench in the investigated region and since some individuals withW2 origin were cultured, attention must be given to the genetic structure and identity ofthe introduced individuals, whether during introduction or reintroduction since biologicaland ecological consequences of the hybridization between the two major clades are stillunknown. Finally, we propose and discuss management and conservation strategies for tenchof both management areas.