Introduced and translocated fish species in the inland waters of Greece

Over the last 7 decades, 23 exotic fish species have been introduced into t he inland waters of Greece. Some introductions were deliberately planned to take advantage of particular ecological or economic qualities of the speci es concerned. These include rainbow trout, Oncorhynchus mykiss (Walbaum), P acific salmon, Oncorhynchus sp., vendace, Coregonus lavaretus (L.), grass c arp, Ctenopharyngodon idella (Valenciennes), and silver carp, Hypophthalmic hthys molitrix (Valenciennes). Other introductions, such as that of pumpkin seed, Lepomis gibbosus (L.), and false rasbora, Pseudorasbora parva (Temmin ck & Schlegel), were unintentional. Further transfers were made of species between various basins within the country, including common carp, Cyprinus carpio L., tench, Tinca tinca (L.), crucian carp, Carassius auratus gibelio (Bloch), bitterling, Rhodeus amarus (Bloch), and Aristotle's catfish, Silu rus aristotelis Garman. Some species have become fully acclimatized and hav e built up important populations. In other cases, the transfers and introdu ctions have had considerable negative impacts, particularly where introduce d species have outcompeted native forms, as in the cases of the mosquito fi sh, Gambusia affinis (Baird & Girard), versus Greek toothcarp, Valencia let ourneuxi (Sauvage), in the western Greek marshes, and of Aristotle's catfis h versus the wels, Silurus glanis L., in Lake Volvi.