Changes in fish species composition in the rivers of the Ararat Plain during the last century

Abstract

Changes in fish species composition in the principal rivers of the Ararat Plain have been assessed over the last century through an analysis of the literature and field studies. A total of 39 fish species, spread across 12 families and 31 genera, have been documented across the Ararat Plain (Araks River basin within southern Armenia and northeast Turkey). In the Armenian section of the plain, 37 taxa have been recorded, including 12 non-native species. Over the past century, the number of fish species in the Metsamor River has increased from 15 to 23, and from 6 to 23 in the Hrazdan River. Currently 16 of the 21 native fish species, previously recorded, are still present in water bodies of the Armenian part of the plain. Rhinogobius cf. similis has been documented for the first time in this region. The primary reasons for the changes in the ichthyofauna composition in the Armenian part of the Ararat Plain are the introduction and subsequent spread of non-native species into reservoirs. This process involves species such as Rhodeus amarus, Knipowitschia caucasica, species of Gobio and invasive non-native species such as Pseudorasbora parva, Carassius gibelio, Rhinogobius lindbergi, R.cf. similis, and Oncorhynchus mykiss.