THE NUTRITION OF A PIKEPERCH, Stizostedion lucioperca Linnaeus, 1758 in THE RIVER NERETVA

The analysis of content of a pikeperch gastro–intestine system was done on the basis of examination of contents of gastro–intestine systems of 27 specimens captured in the accumulations of the river Neretva system. The fish capture was done using the nets set by the members of Ichthyology and Fishing Center at the Faculty of Science Sarajevo, in the period between 17. 07 — 24. 09. 2002. The dissection and fixation of gastro–intestine systems using the 4 % formaldehyde were done on the terrain. The examination of their contents was done in the laboratory of the Faculty of Science Sarajevo. The appearance of a pikeperch in the river Neretva system is result of an accident introduction in the lake Rama (Š k r i j e l j, 1995; Š k r i j e l j and Ma š o v i ć, 2001). The analysis results of the contents of a pikeperch gastrointestine system have indicated very various way of its nutrition caused by capacity of a water ecosystem and a specimen size. Its tendency to the nutrition with the other fish species is expressive in the lakes with the bigger competition with the other fish species and its tendency to cannibalism is expressive in the hydro–accumulations (Salakovac and Mostar). The cannibalism has characterized a pikeperch specimens larger than 30 cm. The specimens in the lake Grabovica (4), shorter than 30 cm, ate the specimens of the zoobenthos settlement. The algae are registered in stomach of one specimen. The survival of important autochthonous species of salmonoids and cyprinids has been endangered because of the established expressive greed of a pikeperch (the larger size specimens). This fact has caused larger negative ecological changes in the central water current of the river Neretva system. These conditions require the measures of control of a pikeperch population density and introduction in general. Comparison of the nutrition of this fish species with the others in the river Neretva accumulations (K a č a n s k i et al., 1976; T r o ž i ć – B o r o v a c, 2002a), it could be concluded that a pikeperch has no competitor. The other fish species have fed on the invertebrates and plants of benthos, accept a rare lake trout Salmo trutta m. lacustris Linnaeus, 1758 specimens which have shown tendency to the greedy way of the nutrition. This paper is the contribution to the knowledge of a pikeperch nutrition in the river Neretva accumulations that is, beside the reproduction, the important character of population growth control of this greedy animal, and in the aim of the survival of the autochthonous ichthyopopulations in the river Neretva system

THE FIRST RECORD AND MORPHOLOGICAL CHARACTERISTICS OF HYBRID OF Rutilus rutilus x Abramis brama MODRAC RESERVOIR, BOSNIA AND HERZEGOVINA

U hidroakumulaciji Modrac kod Tuzle (Bosna i Hercegovina) prvi je put utvrđena prisutnost prirodnog hibrida bodorke i deverike. Na uzorku od 54 jedinke analizirane su morfološke i merističke karakteristike i ihtiomasa. Za svaku su karakteristiku utvrđeni raspon variranja i srednja vrijednost. Razmjeri pojedinih dijelova tijela izraženi su u postocima u odnosu na totalnu dužinu tijela. Od merističkih karakteristika ispitani su broj negranatih i granatih zraka u dorzalnoj, analnoj, prsnoj i trbušnoj peraji, broj ljusaka u bočnoj liniji, broj branhiospina na prvome škržnom luku i broj škržnih zuba. Strukturu populacije hibrida po spolu činila su 42 mužjaka i samo 12 ženki. U dobnoj strukturi ženki dominiraju jedinke dobi 7+ (5 jedinki), 5+ (3 jedinke), dok je iz dobnih klasa 2+, 3+, 4+ i 6+ bila prisutna samo po jedna jedinka. U dobnoj strukturi mužjaka prisutne su jedinke u dobi od 2+ do 7+, uz dominaciju jedinki u dobi 5+ (13 jedinki), dok je najmanje bilo jedinki u dobi 2+ (2 jedinke). Utvrđeno je da jedinke hibrida intenzivno rastu do dobi 4+, a onda nastupa stacionarna faza rasta, karakteristična za oba spola.In Modrac reservoir near Tuzla (Bosnia and Herzegovina) for the first time has been determined the presence of the natural hybrid roach and bream. On the 54 samples morphological and meristic characteristics of hybrids have been analyzed, 22 characteristics of the morphology and ihthyomas are analyzed. For each character the variation and mean values were calculated. Proportion of parts of the body are calculated and given as relative values of total length of the body. Beside morphological other meristic characteristics of hybrids have been tested: the number of unbranched and branched signs in dorsal, anal, pectoral and ventral fins, the number of scales in vertical line, number of scales in horizontal lines over and under, number of gill rakers on first grill and pharyngeal teeth. The analysis of sex and age structure of hybrids in which there were 42 males and 12 females has been done. In the age structure of females the dominant age is up to 7+ (5 samples) and 5+ (3 samples). The age structure of males is from 2+ to 7+, where dominant age is 5+ (13 samples) and 2 samples with age structure of 2+. The hybrids growth is intensive up to age of 4+ and then is stationary phase of growth characteristics for both sexes

GASTROPODS IN THE BASIN OF THE RIVER FOJNIČKA

Prvo detaljno istraživanje gastropoda u slijevu Fojničke rijeke provedeno je tijekom 2001.–2002. godine. Materijal je uzorkovan pet puta u tijeku četiriju godišnjih sezona (listopad 2001. — rujan 2002.) na 11 lokaliteta, i to na sljedeć im vodotocima: Fojnička rijeka, Dragača, Željeznica, Kreševka i Lepenica. Istodobno s prikupljanjem uzoraka makroinvertebrata zoobentosa, mjereni su i neki fizikalno–kemijski parametri (BPK5, temperatura vode, pH–vrijednost, količina otopljenog kisika, zasićenost kisikom i jednokratno mjerenje koncentracije nitrata i fosfata). Imajući u vidu činjenicu da je biodiverzitet gastropoda u Bosni i Hercegovini na dosta niskom stupnju istraženosti, cilj je ovog rada sagledavanje distribucije zajednice gastropoda slijeva Fojničke rijeke. Navedenim je istraživanjima identificirano 11 taksona i 1 468 jedinki gastropoda i činile su 16% od ukupnog naselja makroinvertebrata zoobentosa. Dominantna vrsta na istraživanim lokalitetima jest Ancylus fluviatilis, dok se sporadično susreću vrste Acicula sp., Saxurinator sp. i Valvata piscinalis. Najveći broj vrsta (osam) i najveći broj jedinki (657) zapažen je na lokalitetu ušća Fojničke rijeke u Bosnu.The first detailed investigation of Gastropods in the basin of river Fojnička has been carried out in 2001–2002. The material has been sampled five times during four seasons (October 2001–September 2002) at 11 sites in the following waterways: the rivers Fojnička, Dragača, Željeznica, Kreševka and Lepenica. Measurement of certain physical and chemical parameters (BOD5, water temperature, pH value, amount of dissolved oxygen, saturation with oxygen and one time measurement of concentration of nitrates and phosphates) has been carried out together with collecting of macroinvertebrates of zoobenthos. Since the knowledge of biodiversity of Gastropods in Bosnia and Herzegovina is at the very low level, the main objective of this paper is to give an overview of distribution of Gastropods communities in the Fojnička river basin. In these investigations, 11 taxa of Gastropods and 1468 individuals have been determined. The Gastropods made 16% of total settlement of macroinvertebrates of zoobenthos. Dominant species at investigated sites was Ancylus fluviatilis, while species Acicula sp., Saxurinator sp. and Valvata piscinalis were just sporadically recorded. The largest number of individuals (657) and largest number of species (eight) was recorded at the mouth of the river Fojnička into the river Bosna

LONG-TERM TRENDS IN THE STRUCTURE AND DYNAMICS OF THE FISH COMMUNITIES IN BUŠKO BLATO RESERVOIR

Akumulacija Buško Blato, treća najveća hidroakumulacija u Europi, smještena je u jugoistočnom dijelu krškog Livanjskog polja. Ovaj vodeni ekosustav odlikuje se vrlo bogatom ihtiofaunom i prisutnošću četiri endemske vrste riba. Ihtiološka istraživanja navedene akumulacije bila su u fokusu brojnih istraživanja. Ihtiofauna Buškog Blata bila je izložena promjenama različitih ekoloških čimbenika, što se odrazilo na strukturu i sastav ribljih populacija. Glavni cilj ovog rada bio je procijeniti trenutno stanje i predvidjeti buduće trendove u strukturi i dinamici ihtiofaune na temelju prikupljenih terenskih podataka i sveobuhvatnih analiza iz literaturnih podataka. Rezultati istraživanja pokazali su prisutnost 11 vrsta riba iz četiri porodice, što je najveći broj vrsta riba ikada zabilježenih u ovom ekosustavu. Sander lucioperca, Lepomis gibbosus, Pseudorasbora parva, i Tinca tinca prvi su put zabilježeni u ovom ekosustavu, dok neke prethodno zabilježene vrste nisu pronađene. Rezultati analiza jasno ukazuju na prisutnost prirodne interspecifične konkurencije i značajnu razinu ugroženosti endemskih vrsta riba uzrokovanu ljudskim aktivnostima.Buško Blato Reservoir, the third largest hydro accumulation in Europe, is situated in the south-eastern part of the karstic Livanjsko Polje Valley. This aquatic ecosystem is distinguished by a very rich ichthyofauna and the presence of four endemic fish species. Numerous studies focus on ichthyological researches of Buško Blato Reservoir. Its ichthyofauna has been exposed to changes in ecological factors, which in turn reflected on the structure and composition of fish populations. The main objective of this paper was to assess the current state and predict future trends in the ichthyofauna structure and dynamics based on the field data and comprehensive analyses of literature data. The results of the research indicated the presence of 11 fish species from four families, which is the largest number of fish species ever recorded in this ecosystem. Sander lucioperca, Lepomis gibbosus, Pseudorasbora parva and Tinca tinca were recorded for the first time in this ecosystem, while some previously recorded species were not found. The results of the analyses clearly indicate the presence of natural interspecific competition and significant level of threats to the endemic fish species caused by human activities

IHTIOFAUNA RIJEKE BIJELI DRIM (KOSOVO)

This paper presents data obtained from literature and by sampling of the fish fauna in the Drini i Bardhë River (the White Drin). A table containing all 18 fish species of Drini i Bardhë River, which were collected by the authors in the period between 2005 and 2007, is presented. The results from the two–year research period in Drini i Bardhë River show that the composition of fish fauna is very complex. In total, 457 individual fish of different taxa were caught or 164.9 kg of ichtyomass. In six selected sampling sites of the river, 18 taxa fish belonging to 6 families were found. Based on complex research we can conclude that the Drini i Bardhë River is an ecosystem with relatively favorable ecological conditions for the development of ichthyofauna.Ovaj članak sadržava podatke o ihtiofauni rijeke Bijeli Drim dobivene iz analize prikupljenih uzoraka ribljih vrsta i usporedbom s dostupnom literaturom. Sastav ihtiofaune rijeke Bijeli Drim obuhvaća 18 ribljih vrsta prikupljenih tijekom 2005. i 2007. godine. Rezultati dvogodišnjeg istraživanja u rijeci Bijeli Drim upućuju na vrlo složen sastav ihtiofaune te rijeke. Ukupno je ulovljeno 457 jedinki različitih vrsta riba koje čine ukupnu ihtiomasu od 164,9 kg. Na šest izabranih postaja istraživanja u uzdužnom profilu rijeke ustanovljeno je 18 ribljih vrsta koje pripadaju šesterim porodicama. Na osnovi iscrpnih razmatranja može se zaključiti da je rijeka Bijeli Drim ekosustav s relativno optimalnim ekološkim uvjetima, ali zbog izravnih negativnih raznih antropogenih utjecaja razvoj ihtiofaune u toj rijeci slabi

THE QUALITATIVE-QUANTITATIVE CONTENT OF JUVENILE STONEFLIES (PLECOPTERA) IN MACROZOOBENTHOS

A study was carried out on the changes in content and abundance of local juvenile stonefly communities species at the sites Garež, Delijaš and Balbašići during autumn of 2009 and spring and summer of 2010. A total of 1585 specimens were collected using a mash for zoobentos, out of which 541 were collected at the site Garež, 486 at the site Delijaš and 558 at the site Balbašići. The specimens were categorized into five families and 20 species. The most abundant species out of the total number at the site Garež was Leuctra nigra (73,94%), at the site Delijaš Perla marginata (19,96%), and at the site Balbašići Leuctra nigra (25,63%). The highest diversity indeces were at the site Delijaš, and the highest eveness was at site Balbašići.\ud \ud Key words: Crna Rijeka River, communities of juvenile stoneflies, Plecopter

EKOLOŠKA, MORFOLOŠKO-TAKSONOMSKA I HEMATOLOŠKA KARAKTERIZACIJA SMUĐA (SANDER LUCIOPERCA, LINNAEUS 1758) IZ NERETVANSKIH HIDROAKUMULACIJA

Ecological, morphological-taxonomic and haematological features of pike perch (Sander lucioperca, Linnaeus 1758) as introduced species in reservoirs on the river Neretva in Bosnia and Herzegovina is presented in this paper. Field research has been carried out in the period from November 2009 to November 2010. The analysis of morphological-taxonomic paremeters has been carried out on 103 specimens, with 54 used for the analysis of haematological parameters. From an ecological standpoint, populations of pike perch from the „lakes“ on the river Neretva exhibit trends towards an increase in density. These populations include specimens of various age, and they show a high degree of adaptibility to the reservoir\u27s ecosystems. Morphological features of specimens show the presence of several generations, which indicates that this species successfully spawns in the investigated ecosystems. The largest variation coefficient by season, within seven measured haematological parameters, have haematological indices MCV, MCH and MCHC.U radu su prikazani ekološki, morfološko-taksonomske i hematološke značajke smuđa (Sander lucioperca, Linnaeus 1758) kao introducirane vrste u hidroakumulacijama na rijeci Neretvi u Bosni i Hercegovini. Terenska istraživanja su provedena u periodu od novembra 2009. godine do novembra 2010. godine. Ukupno je analizom za morfološko-taksonomske parametre obuhvaćen uzorak od 103 jedinke od kojih je 54 podvrgnuto istraživanjima hematoloških parametara. Sa aspekta ekologije populacija smuđa u neretvanskim „jezerima“ ima tendenciju povećanja gustine, obuhvaća jedinke različite životne dobi i pokazuje visok stupanj adaptiranosti u ekosistemima hidroakumulacija. Morfološke karakteristike jedinki pokazuju prisustvo većeg broja generacija što ukazuje da se ova vrsta uspješno mrijesti u istraživanim ekosistemima. Od ukupno sedam hematoloških parametara najveći koeficijent variranja po sezonama ustanovljen je kod hematoloških indeksa MCV, MCH i MCHC

THE ICHTHYOFAUNA OF DRINI I BARDHË RIVER (KOSOVO)

This paper presents data obtained from literature and by sampling of the fish fauna in the Drini i Bardhë River (the White Drin). A table containing all 18 fish species of Drini i Bardhë River, which were collected by the authors in the period between 2005 and 2007, is presented. The results from the two–year research period in Drini i Bardhë River show that the composition of fish fauna is very complex. In total, 457 individual fish of different taxa were caught or 164.9 kg of ichtyomass. In six select%ed sampling sites of the river, 18 taxa fish belonging to 6 families were found. Based on complex research we can conclude that the Drini i Bardhë River is an ecosystem with relatively favorable ecological conditions for the development of ichthyofauna

IHTIOFAUNA RIJEKE BIJELI DRIM (KOSOVO)

This paper presents data obtained from literature and by sampling of the fish fauna in the Drini i Bardhë River (the White Drin). A table containing all 18 fish species of Drini i Bardhë River, which were collected by the authors in the period between 2005 and 2007, is presented. The results from the two–year research period in Drini i Bardhë River show that the composition of fish fauna is very complex. In total, 457 individual fish of different taxa were caught or 164.9 kg of ichtyomass. In six selected sampling sites of the river, 18 taxa fish belonging to 6 families were found. Based on complex research we can conclude that the Drini i Bardhë River is an ecosystem with relatively favorable ecological conditions for the development of ichthyofauna.Ovaj članak sadržava podatke o ihtiofauni rijeke Bijeli Drim dobivene iz analize prikupljenih uzoraka ribljih vrsta i usporedbom s dostupnom literaturom. Sastav ihtiofaune rijeke Bijeli Drim obuhvaća 18 ribljih vrsta prikupljenih tijekom 2005. i 2007. godine. Rezultati dvogodišnjeg istraživanja u rijeci Bijeli Drim upućuju na vrlo složen sastav ihtiofaune te rijeke. Ukupno je ulovljeno 457 jedinki različitih vrsta riba koje čine ukupnu ihtiomasu od 164,9 kg. Na šest izabranih postaja istraživanja u uzdužnom profilu rijeke ustanovljeno je 18 ribljih vrsta koje pripadaju šesterim porodicama. Na osnovi iscrpnih razmatranja može se zaključiti da je rijeka Bijeli Drim ekosustav s relativno optimalnim ekološkim uvjetima, ali zbog izravnih negativnih raznih antropogenih utjecaja razvoj ihtiofaune u toj rijeci slabi