L. Forró szerk.: Miscellanea Zoologica Hungarica 8. 1993 (Budapest, 1993)
Vida, A.: Expected effects of the Gabčikovo river barrage system on the ichthyofauna of the Szigetköz and its values
Qualification of the side branch systems in the flood-plain and the expected changes according to the number of valuable fish species are shown in Fig. 2. Fig. 2. Qualification of the side branch systems in the flood-plain and the expected changes according to the number of valuable fish species. Disconnected backwuters The disconnected backwaters became isolated from the flood-plain due to older regulating activities. Their fish fauna was already formed and stabilized before the divertion. The special physical and chemical parameters are tolerated only by a few species. Most of these species are, due to the loss of such water types, endangered. Umbra krameri occurs here, which is endemic to the Carpathian Basin, and is included in the Red Data Book of Hungary (Bankovics 1989). The assemblage of this water type is typically marshy. Due to the divertion, the water disappeared from practically all disconnected backwaters, so their fauna can be regarded as eliminated. The few short reaches that could have remained were so shallow that the birds and other piscivores probably consumed the last surviving specimens. Characteristic species: Umbra krameri, Cobitis taenia, Misgurnus fossilis, Carassius auratus, Tinea tinea, etc. Species probably disappeared in the past few months: all species, i.e. Esox lucius, Umbra krameri, Cyprinus carpio, Alburnus alburnus, Carassius carassius, C. auratus, Ctenopharyngodon idella, Gobio gobio, Leucaspius delineatus, Leuciscus cephalus, L. idus, Pseudorasbora parva, Rhodeus sericeus amarus, Rutilus rutilus, Scardinius erythrophthalmus, Tinea tinea, Cobitis taenia, Misgurnus fossilis, Noemacheilus barbatulus, Gasterosteus aculeatus, Lepomis gibbosus, Perca fluviatilis, Proterorhinus marmoratus. Fig. i. Qualification of the disconnected backwaters and the expected changes according to the number of valuable fish species.
