Fishfauna From the Lowland Mure ş River and the Floodplain Natural Park Area (Western Romania)

FISHFAUNA FROM THE LOWLAND MURE Ş RIVER (ROMANIA) AND THE FLOODPLAIN NATURAL PARK AREA (WESTERN ROMANIA)

Ilie C ătălin TELCEAN *, Diana CUP ŞA*

*University of Oradea, Faculty of Science, Department of Biology, Oradea, Romania Corresponding author: Ilie C ătălin Telcean, University of Oradea, Faculty of Science, Department of Biology, 1 Universitatii Str., 410087 Oradea, Romania, tel.: 0040259408161, fax: 0040259408461, e-mail: [email protected]

Abstract. The lowland Mure ş river has approximately 120 km in length, thereof more than 80 kilometers are comprised on the Mure ş Floodplain Natural Park that was established since the year 2007. This river stretch has different biotopes with lotic or lentic semblances with very characteristic and diverse fish fauna. Along the lowland main stream a system of canals, marshes and pools are connected. The results of repeated ichtiological surveys carried out during the years 1998 – 2001 and 2004 reveals that 48 fish species live in this river sector and other 2 species has uncertain presence. Most of the species from the river mainstream has maintain their former abundance (24 species) while other 16 fish species has increased their abundance. The burbot Lota lota and Zingel zingel becomes frequent in the lowland Mure ş, probably as consequence of their population renewal. The number of fish species that having undergone regression is less (4 species) and the exotic species present here are limited to 8 species. The major threatening factors in the lowland Mure ş represents the mineral aggregate extractions directly from the riverbed and the waste waters spill. Subsequent, the meanders and backwaters shortening or cutting down has a negative impact on the fish populations.

Keywords: Fishfauna, Mure ş Floodplain Natural Park, changes in species range, Romania

INTRODUCTION fishes have a large distribution in all of western Romanian rivers [22, 23, 24]. First records on the Mure ş river fishfauna were Due to the water pollution on the decades of 70’ provided by Rotarides [20] Jasfalusi [17] and B ăcescu and 80’ a number of species have become rare or [1]. These papers are devoted to the generally fishfauna extremely rare [19]. Some fishes such as Acipenser from the Transylvanian rivers and mention the Mure ş ruthenus, Abramis brama, Carassius carassius, river. More comprehensive data are furnished by Cyprinus carpio and Stizostedion lucioperca was Bănărescu [4, 5] in the two monograph works practically extinct species. Some moderate rheophilic dedicated to the systematic of bony fishes and to the species from lower Mure ş river such as Vimba vimba, lampreys. The data concerning the Mure ş fishfauna are Abramis ballerus and Gobio albipinnatus reached the the subject for successive papers [3, 4, 6, 7, 8, 9]. The upper stretches of the river [19]. Water pollution has a data mentions the species distributions along the main major influence on the river’s fishfauna [18, 21, 22, 27, Romanian rivers including also the river Mure ş. A 29]. The human impact on the fishfauna is now more special contribution concerning the species distribution diverse. Nearby the waste spill and the riverbed in the Mure ş river system is published in 1957 [6] and modifications, the fisheries activities can modify the later by Nalbant [19] who completed the species list fishfauna in the lowland rivers and canals [24]. During with ecological observations. The last paper represents the last decade the negative impact of water pollution the only recent published data concerning the Mure ş were diminished in the lower section of Mure ş. Thus fishfauna. It was mentioned more than 50 fish species some of the fish species has restored their former along the entire river. The fishfauna changes that is abundance. ascertain in the last decade are to motivate a new survey on this river. MATERIALS AND METHODS The subjects concerning the endemic fishes that live in different rivers from the Mure ş drainage system The fish species were identified during repeatedly are discussed in recent papers [10, 11, 19]. collecting trips which were conduct both on the river Morphological variation observed on the mainstream and the adjoined canals, marshes and representatives of Sabanejewia genus from different ponds. The study was performed in two steps: 1998- river stretch of Mure ş river was explained in several 2001 the investigations upon the fishfauna from the papers [6, 7, 10, 19]. The Mure ş river is the only that entire river and in the year 2004 investigations limited have no intergrades population between the two to the fish species which live in the lowland river. The loaches species Sabanejewia balcanica and S. ichtiological surveys were focused on the general bulgarica . In the other northwestern Romanian rivers fishfauna diversity and the species distribution. Thus in which the two loaches are distributed (Timi ş, Somes, we can observe the changes in species distribution Crisuri system), the lowland stretch has an intergrades along the river and the species abundance. zone. The present paper is referring to the results of the There are only four exotic fishes which are ichtiological surveys upon the lowland river fishfauna. mentioned in the lower Mure ş [19]. The recent The samples on the Mure ş Floodplain Natural Park investigations are proved that another 4 exotic fishes were located as follows: Bodrog, Pecica, Prundu Mare, are distributed on the lowland river both on Romanian Şeitin, N ădlac and Cenad. The upstream stretch was and Hungarian stretches [14, 15]. The presence of the investigated in two sites: near the Zam defile and near black bullhead Ictalurus melas on the small canals and the locality Mândruloc. pools was first mentioned from Crisuri rivers system The collecting methods were combined using both [18]. According to recent data it seems that the exotic the fishing nets (mesh size 5mm) and electro-narcosis

132 Analele Universit ăţ ii din Oradea, Fascicula Biologie Tom. XVI / 1, 2009, pp. 131-135 device (type IUP 12V, 4-10 A, 360W). The electric because of the habitats without swift streams. The fish fishing procedure was according to the CEN directive specimens were identified and recorded at the sampling [30] using pulsed direct current (PDC).The applied sites and then released. In some cases additional methods combine the boat fishing and fishing directly information from local competent people and anglers from the riverbanks. The stop nets were not necessary associations was used.

Fig. 1. The sampling in the lowland Mure ş River

RESULTS alburnus, Aspius aspius, Gobio kessleri and Rhodeus sericeus . A total number of 48 fish species were identified in Species identified on the mainstream river the lower sector of the Mure ş and neighboring canals between localities Pecica and Cenad and ponds (Table 1). Approximately a number of 29 of The river biotope is characterized here by the these species are widely distributed downstream to tendency of homogeneity on flowing velocity and the defile from the locality Zam until the locality predominance of sandy riverbed. The slopes especially Mândruloc (Figure 1). Others 19 fish species are those with vegetation such as Potamogeton and Trapa distributed predominantly on still waters and canals are densely populated by early stages of different from a limited sector in the lowland river. species. The crevices from the arduous shores are best Species identified on the mainstream river hiding places for many species. between localities Zam and Mândruloc On the mainstream of this river stretch were This river sector has characteristic a non identified 44 fish species which belongs to the homogenous flowing velocity and alternant pebbly and following taxa: Acipenseridae (one species), gravels bottoms. Cyprinidae (22 native and 5 exotic species); Cobitidae We identified here a total number of 26 fish (4 species), Siluridae (one species); Ictaluridae (2 species. The majority belongs to Cyprinidae family (13 species); Esocidae and Gadidae (each with a single are natives and 3 exotic). The others species are species), Percidae (7 species) Centrarchidae (one representatives of the Cobitidae family (2 species), species). Siluridae, Esocidae and Gadidae (each with a single Acipenseridae :: Acipenser ruthenus ; Native species), Percidae (3 species); Centrarchidae (one cyprinids : Rutilus rutilus, Leuciscus cephalus, species). Leuciscus idus, Scardinius erythrophthalmus, Aspius Native cyprinids : Rutilus rutilus, Leuciscus aspius, Alburnus alburnus, Blicca bjoerkna, Abramis cephalus, Scardinius erythrophthalmus, Aspius aspius, brama, A. ballerus, A. sapa, Vimba vimba, Pelecus Alburnus alburnus, Alburnoides bipunctatus, Abramis cultratus, Chondrostoma nasus, Leucaspius delineatus, ballerus, Vimba vimba, Chondrostoma nasus, Rhodeus Rhodeus sericeus, Gobio gobio, G. albipinnatus, sericeus, Gobio gobio, G. kessleri, Barbus barbus. Barbus barbus. Cyprinus carpio, Tinca tinca ; Exotic Exotic cyprinids : Carassius gibelio, Pseudorasbora cyprinids : Carassius gibelio, Pseudorasbora parva parva and Hypophthalmichthys molitrix . Cobitidae : Hypophthalmichthys molitrix , H. nobilis and Cobitis elongatoides, Sabanejewia balcanica ; Ctenopharyngodon idella ; Cobitidae : Misgurnus Siluridae : Silurus glanis ; Esocidae : Esox lucius ; fossilis, Cobitis elongatoides, Sabanejewia balcanica, Gadidae (Lotidae): Lota lota ; Percidae : Perca S. bulgarica ; Siluridae : Silurus glanis; Ictaluridae : fluviatilis, Gymnocephalus schraetser, Zingel zingel, Z. Ictalurus nebulosus, I. melas ; Esocidae : Esox lucius ; streber ; Centrarchidae Lepomis gibbosus . Gadidae (Lotidae): Lota lota ; Percidae : Perca The most frequent species were Chondrostoma fluviatilis, Gymnocephalus schraetser, G. baloni, G. nasus, Leuciscus cephalus, Barbus barbus, Alburnus cernuus, Zingel zingel, Z. streber, Stizostedion (Sander) lucioperca ; Centrarchidae Lepomis gibbosus .

133 Fishfauna From the Lowland Mure ş River and the Floodplain Natural Park Area (Western Romania)

There are two rare species: Stizostedion volgense The most rheophilic representatives of Percidae fish (Volga’s pike perch) which are recorded from the family lives almost exclusive in the river mainstream Hungarian sector of the river, close to the locality (Stizostedion lucioperca, Gymnocephalus schraetser, Cenad and the tubenose - Protherorhinus marmoratus Zingel zingel, Zingel streber ). They are also widely (species with marine origin that extend its area far distributed in the lowland Mure ş. The Percidae species away on the Black Sea tributaries). The last species is which lives predominantly in the canals system and also frequent in Tisa and other rivers and ponds from ponds are Perca fluviatilis, Gymnocephalus baloni, G. Hungary. cernuus . There is occurring as well the exotic species Species identified on the canals and neighboring Lepomis gibbosus representative for the Centrarchidae ponds family. There are no recent reliable data on the The slow flowing and the standing waters are presence of Stizostedion volgense on the lower Mure ş. represent a characteristic biotope from the lowland It is recorded frequent from the Hungarian stretch of Mure ş. The canals system connected to the river are the river and surely it is present also on the Romanian natural hideaway for many fishes. The well vegetated sector. canals and ponds from the territory of the natural park The burbot Lota lota is became more frequent on are favorable biotope for crucian carp - Carassius the lowest river sector corresponding to the Mure ş carassius and Tinca tinca . The both species are rare Floodplain Natural Park. Previous data [19] mention and their populations were drastically reduced in the this species only from the upper river (between locality last decades. The ponds near Bezdin monastery are Senetea and Gorne şti). Is possible that the specimens such of habitats for Carassius carassius . from lower Mure ş are originated from lowermost river In the canals near locality Cenad and neighboring from Hungary and Tisa river. This species prefers cold ponds are occurred 22 fish species. There are 11 native waters and in some years reach the tributaries. Another Cyprinid species : Rutilus rutilus, Leuciscus idus, quasi-migratory fish species are Pelecus cultratus Scardinius erythrophthalmus, Blicca bjoerkna, which is occurred predominantly in Tisa river and Abramis brama, Abramis sapa, Leucaspius delineatus, Danube. This species migrates occasionally on the Rhodeus sericeus, Cyprinus carpio, Carassius tributary from the left side of Tisa river but has not carassius, Tinca tinca ; 3 exotic Cyprinid species : being a permanent dweller in these rivers. Carassius gibelio, Pseudorasbora parva, The small sized fish species which are large Ctenopharyngodon idella. There are two Ictaluridae distributed on the river mainstream are the loaches species Ictalurus nebulosus and I. melas . The last one Sabanejewia balcanica and Sabanejewia bulgarica . is less distributed on the canals. The families Esocidae The first are characteristic in the middle and lowland and Centrarchidae are represented here as well by a Mure ş river and the second ( S. bulgarica ) became more single species ( Esox lucius and Lepomis gibossus ). The frequent only in the lowland river beginning to Periam Percid fishes are represented here by 4 species: Perca Port locality (near Pecica) until the Tisa river fluviatilis, Gymnocephalus baloni, G. cernuus and confluence. Both species S. balcanica and S. bulgarica Stizostedion lucioperca. The marshes from lowland has no intergrades in lowland Mure ş [19]. Others rivers Mure ş is the optimal habitat for another rare species from north-western Romania has such of intergrades on Misgurnus fossilis . the contact area of these species. The gudgeon species Gobio gobio, G. kessleri and DISCUSSIONS G. albipinnatus are gregarious fishes and have no homogenous distribution. It is distributed according to The Acipenseridae family representative species the riverbed texture. The majority of Gobio kessleri Acipenser ruthenus occurs in the lower river and specimens is finding on the pebbly bottoms and probably in the middle river from the locality Aiud moderated swift waters. The other Gobio albipinnatus until Zam. Former records of this species [19] from the is forming large agglomerates groups on the still waters Mure ş river is not based on captured specimens. with sandy bottoms. This species reach frequent the However this species are captured periodically by canals mouths in the lowland river. The white gudgeon fishermen downstream to Prundu Mare isles on the G. albipinnatus together with loach Sabanejewia Mure ş Floodplain Natural Park. balcanica are representative species in fish A special remark is need upon the two Leuciscus communities established on lowland Mure ş river. species: L. leuciscus is a rare species in the lowland Species that are maintain their abundance in the Mure ş and has undergone numerical decline in the lowland river; majority of Romanian rivers. This species is There are 23 species which were not significant maintaining former abundance in Tisa river and Crisul affected by human activities in the last decade (Table Repede. The other representative of this genus, 1). Majority of these are rheophilic species: Leuciscus boristhenicus ( Petroleuciscus boristhenicus ) Alburnoides bipunctatus, Gobio kessleri, Abramis was recorded by a single specimen from a canal near ballerus, Vimba vimba, Pelecus cultratus, Gobio the fishery of N ădlac [19]. The presence of this species kessleri, Barbus barbus . Others are moderate on this area cannot be explained by natural migrations rheophilic species: Leucaspius delineatus, Abramis or other possibilities. However this species was not brama, Abramis sapa, and Cyprinus carpio . The found again. This species occurs in the Danube Delta rheophilic Percidae Zingel streber, Zingel zingel, and Comana ponds near Bucuresti. Gymnocephalus schraetser, Stizostedion (Sander) volgense needs a special remark. These species are

134 Analele Universit ăţ ii din Oradea, Fascicula Biologie Tom. XVI / 1, 2009, pp. 131-135 vulnerable to the water pollution. Thus their population The others fishes are ubiquitous Perca fluviatilis, renewal coincides with the reduction of amount of Silurus glanis, Gymnocephalus baloni, and Esox lucius . waste waters spill along the upstream Mure ş river and Their distribution covers both the lowland river and the tributaries. This phenomenon is registered recently on canals system that adjoined the mainstream. this river.

Table 1. Fish species from the lowland Mure ş river

Current Fish species Occurence No. River mainstream Channels and ponds 1 Acipenser ruthenus + - 2 Rutilus rutilus ++ ++ 3 Leuciscus cephalus ++ + 4 Leuciscus leuciscus ? - 5 Leuciscus borysthenicus - ? 6 Leuciscus idus ? ? 7 Scardinius erythrophthalmus ++ ++ 8 Aspius aspius ++ - 9 Alburnus alburnus ++ + 10 Alburnoides bipunctatus + - 11 Blicca bjöerkna ? + 12 Abramis brama + + 13 Abramis sapa + + 14 Abramis ballerus + ++ 15 Vimba vimba + + 16 Pelecus cultratus + - 17 Chondrostoma nasus ++ - 18 Leucaspius delineatus + ++ 19 Rhodeus sericeus ++ ++ 20 Gobio gobio ++ ++ 21 Gobio kessleri + - 22 Gobio albipinnatus ++ - 23 Barbus barbus + - 24 Cyprinus carpio + + 25 Carassius carassius - ↓ 26 Tinca tinca ↓ ↓ 27 Carassius gibelio* ++ ++ 28 Pseudorasbora parva* ++ ++ 29 Ctenopharyngodon idella* + + 30 Hypophthalmichthys molitrix* ++ + 31 Hypophthalmichthys nobilis* + + 32 Misgurnus fossilis ↓ ↓ 33 Cobitis elongatoides + + 34 Sabanejewia balcanica ++ - 35 Sabanejewia bulgarica + - 36 Silurus glanis + + 37 Ictalurus nebulosus* + ++ 38 Ictalurus melas* - ++ 39 Esox lucius + + 40 Lota lota ++ - 41 Lepomis gibbosus* ++ ++ 42 Perca fluviatilis + + 43 Gymnocephalus cernuus - + 44 Gymnocephalus baloni + + 45 Gymnocephalus schraetser + - 46 Stizostedion (Sander) lucioperca ↓ ↓ 47 Stizostedion (Sander) volgense + ? 48 Zingel zingel ++ - 49 Zingel streber + - 50 Potherorhinus marmoratus ( P. semilunaris ) - ?

+ = present and stationary effectives; ++ = increasing effectives; ↓ = numerical regress; ? = uncertain; * = exotic fish

Species that are increasing their effectives in the waters which increases the total amount of organic lowland river: suspensions and organic detritus. As a consequence the There are 12 species (those are not including the available nutriments increase. The others species are exotic species). The majority of these are favored by Aspius aspius, Rhodeus sericeus, Gobio albipinnatus, human activities. Species Scardinius erythrophthalmus, Zingel zingel and Lota lota . These are indirect favored Alburnus alburnus, Leuciscus cephalus, Rutilus rutilus, by reduction of industrial waste waters that are recently Chondrostoma nasus, Gobio gobio and Sabanejewia befallen. The ostracophile fish Rhodeus sericeus find balcanica were favored by the spill of household waste more specimens of Anodonta and Unio bivalve

135 Fishfauna From the Lowland Mure ş River and the Floodplain Natural Park Area (Western Romania) mollusks in less polluted waters. This offers conditions [15] Harka, A., Sallai, Z, (2004a): Magyarorszag halfaunaja, for the species spawn. The adjacent canals and pools Nimfea Termeszetvedelmi Egyesulet, Szarvas Hungary, pp. are the suitable biotopes for this species due to the 269. [16] Harka, A., Szepesi, Zs., (2004b): A tarka geb presence of bivalve mollusks. (Protherorhinus marmoratus Pallas 1811) megjelenese es Fish species having undergone regression terjedese a Zagyva vizrendszereben. Halaszat, 97/1: 38-40. 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