Original scientific paper
STATE AND EXPLOITATION OF THE FISH FUND IN THE RIVER SAVA FROM PODSUSED TO STRELEČKO
Dobrila Habeković
; Institut za stočarstvo i mljekarstvo, Fakultet poljoprivrednih znanosti Sveučilišta u Zagrebu, Zagreb
Josip Papović
; Istraživačko-razvojni centar za ribarstvo, Fakultet poljoprivrednih znanosti Sveučilišta u Zagrebu, Zagreb
Abstract
Prior to reconstruction of the river Sava and building .of the hydroelectro power plant in the region from Podsused to Strelečko ichthyological investigations were carried out to establish the existing state of the ichtyofauna. The investigations included catch of fish with different fishing gear in one-time collections of samples in the summer of 1985, during a very low water level on 4 characteristic locations (I-Zaprešić, II-Jankomir and Jarun, III-Ivanja Reka, IV-Tisina). The qualitative and quantitative state of the fish fund was established, along with .the growth rate and ichthyomass, and fishing exploitation. Location I is inhabited by a transit lowland species of fish. Approximately 30 fish species are present, and the most numerous is the family of carp. In this region the chub is dominant (Tables 1-3). The area is poor in highbred species of fish. The average yearly growth-rate of this flow of the Sava River is 32 kg/ha, while the biomass of the fish is 65 kg/ha. Location II, with a flow from the river Krapina (often very polluted), which has a significant influence on the state of that part of the river. The same species of fish are present (Tables 4-6) as in the former upstream region, along with the joining fish of the lowland flows Leuciscus idus L. The growth rate of fish is 30 kg/ha, and the ichthyomass is 60 kg/ha. Location III of the river Sava more and more assumes the characteristics of the lowland rivers. The area is rich in a mixture of fish populations and is inhabited by about 40 fish species. The prevailent species is the carp. The chub fish and Leuciscus idus L. are dominant (Tables 7-9). The average yearly growth rate is about 50 kg/ha, while the total mass is 100 kg/ha. The lowland area, location IV, is being inhabited by fish important far the barbel-carp fish area. There are still plenty chub, a good number of Leuciscus idus L., along with the remaining fish species (Tables 10-12). This area is highly polluted which is evidently maintained on the structure of the fish fund. The ichtyomass of fish is 70 kg/ha, and the yearly growth rate 30 kg/ha. The components of the fish population according to the similarity index are given in Tables 13 and 14. In the management sense, locations I and II belong to the community of sports fishing -societies Zagreb. Management of the last 2 areas, locations III and IV, is carried out by the community of sports fishing societies Zagreb, Ivanić Grad and Sisak. In the exploitation of the fish fund (according to fish catching areas in Tables 15 and 16), the sports fishing recreation fisherman are dominant with 99.6%, who are involved in the total catch with 75%. Individual private fishermen (0.4%) make up 25'% of the total catch of fish on locations II, III, and IV of the Sava region.
Keywords
ichthyofauna; Sava river; Podsused; Strelečko
Hrčak ID:
77093
URI
Publication date:
22.5.1991.
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