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Exploatation characteristic of barbel, nase, chub and ide in the riverine and lake ecosystems
Prokeš, Miroslav ; Baruš, Vlastimil ; Peňáz, Milan
The exploatation characteristics of four potamodromous fish species, barbel (Barbus barbus), nase (Chondrostoma nasus), chub (Leuciscus cephalus) and ide (L. idus) obtained in the riverine and so-called lacustrine (man-made lake) ecosystem, exemplified on the fishing ground Dyje 7 on the river Dyje, is documented. Based on the analyse of many-year catch data of mentioned fish species, the influence of stream fragmentation was revealed upon the abundance reduction of natural populations of rheophilic fish species of concerning Dyje river sectin (located at the Mušov reservoir), as well as a necessity of strengthening these populations in the adjacent stream sections, especially by stocking of artificially produced fry, and in near future also by the construction of the new functional fish ladders.
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Using of biocide Diazinon 60 EC in fish farming and its toxicity for fish and another water organisms
Máchová, J. ; Prokeš, Miroslav ; Faina, R. ; Kroupová, H. ; Svobodová, Z. ; Peňáz, Milan ; Baruš, Vlastimil
Diazinon 60 EC (chemical insecticide, organophosphate, active substance diazinon at a concentration of 600 g/l) is used in fish-farming in well-founded cases as a biocide to supress excessive propagation of coarse daphnian zooplankton (used concentration of Diazinon 60 EC 0,010 mg/l). Diazinon 60 EC is highly toxic for daphnian zooplankton (48hEC50 = 0,00029 mg/l by the using of artificially prepared adulterating water according to the standard and 48hEC50 = 0,0029 mg/l by the using of pond water). Toxicity of Diazinon 60 EC is markedly lower for other water organisms (96hLC50 for Poecilia reticulata, Cyprinus carpio and Orcorhynchus mykiss are in the range 3-10 mg/l and 72hIC50 for Desmodesmus subspicatus = 10 mg/l). At the concentration of 0,01 mg/l (i.e. 100 g per 1 ha at 1 m mean depth of the pond), Diazinon 60 EC can highly selectively eliminate daphnian zooplankton, causes no harm to fish and is reltively quickly decomposed in the aquatic environment.
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Individual growth and weight condition of the common carp (Cyprinus carpio m. domestica) in the Nové Mlýny Reservoir (preliminary results)
Habán, V. ; Prokeš, Miroslav ; Baruš, Vlastimil ; Mareš, J.
Individual tagging of the carp (C. carpio f. domestica) 2-year stockfish (K2) was initiated in 2001. In total, 10 thousands specimens were so far tagged with the anchor plastic tags and released into the Nové Mlýny Reservoir on the River Dyje in 2001-2005. According to the 36 registered recaptures (in 2004), the carp reached in the third year of life after 11-12 months exposition in the reservoir (D 316-317, mean 345.3), a body mass of 1500-3900 g (mean = 2264.4+-802.6 g) and a total length of 420-530 mm (mean = 464+-33 mm). These values reveal high trophic sources existing in the Nové Mlýny Reservoir being filled in 1988. When compared with similar data from fishponds of the Czech and Slovak Republics, the growth rate observed showed to be similar or even higher.
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Growth comparison of the (1+) juvenile sterlet (Acipenser ruthenus) by using experimental and commercial diet
Baránek, V. ; Prokeš, Miroslav ; Baruš, Vlastimil ; Peňáz, Milan ; Cileček, M. ; Mareš, J. ; Jirásek, J. ; Spurný, P.
The aim of this experiment was to check the growth rate of the (1+) juvenile sterlet. The experiment was proceeded during the 42-days period (25 July - 4 September 2005) in the hatchery of the Pohořelice Pond Fisheries. The fish were kept in four flow through tanks. In total, 45 individuals were stocked in each tank. Fish were fed by experimental (44/12) and commercial diet (Pro Aqua Brutfutter 57/15, Skretting) in two repetitions. Our experiment confirmed very good growth ability of the juvenile sterlet, together with low FCR parameter. Sterlet may be considered as an appropriate fish for intensive aquaculture and also, as a native species of the Czech Republic for stocking into Czech running waters.
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Converting of juvenile zander (Sander lucioperca) to artificial diet (preliminary results)
Baránek, V. ; Mareš, J. ; Prokeš, Miroslav ; Jirásek, J. ; Spurný, P.
Weaning success of pond-reared zander (Zander lucioperca) fry was evaluated using three different converting methods: direct converting to dry feed (Bio-Optimal Start 0.5-0.8 mm) – variant A, three– day application of semi-moist feeding mixture on the base of fish – variant B and three-day application of semi-moist mixture + three-day co-feeding of semi-moist mixture and dry feed. These methods were evaluated regarding specific growth rate (SGR), Fulton´s factor of weight condition (FWC), survival and cannibalism. The average onset total length of fish was 35.22 ± 2.15 mm and the average individual weight was 0.31 ± 0.05 g. There were 600 individuals in each circular tank. The initial stock density was 0.62 g.l-1 (2 fish.l-1). The water temperature during this experiment fluctuated in intervals 22 – 24oC. Fish survival during a 14-day period of rearing ranged from 34.33% [C] to 50.33% [A]. Variant A and B were achieved better weaning performance than variant C regarding all parameters.
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Occurrence and characteristics of ide (Leuciscus idus Linnaeus, 1758) catches in drainage area of the Morava River
Prokeš, Miroslav ; Baruš, Vlastimil ; Peňáz, Milan
The ide, Leuciscus idus belongs to autochthonous, less numerous and endangered (vulnerable) fish species of the Czech Republic. In 2004, the fishing on ide was conducted on 51 non-salmonid (NS) fishing-grounds of the Moravian Anglers Union (MAU) on water area of 4622.4 ha. In total, 432 ides (= 0.31 ind.ha-1; 0.25 % of all captured fish) and 332 kg of ide biomass (= 0.23 kg.ha-1, = 0.10 % of total mass of captured fish) were captured in 2004. Mean individual mass of ide was 0.78 kg. In the period 1990-2004, 0.11 ind.ha-1 (= 0.067 % of all captured fish) and 0.075 kg.ha-1 (= 0.035 % of total mass of captured fish) in the NS fish-grounds of MAU were captured yearly. During 1953-1978, 1.67 ind.ha-1 and 1.41 kg.ha-1 of the ide were captured yearly in the riverine fishing-ground Dyje 7. General trend of catches is decreasing. Legislative species protection, artificial reproduction and restocking of fish fry and 1+ juveniles were realized.
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Genus Cyprinus Linnaeus, 1758 - actual review on species diversity
Baruš, Vlastimil ; Peňáz, Milan ; Prokeš, Miroslav
In the genus carp (Cyprinus) is included currently 22 taxons in species levels and his fission into two subgenus: Cyprinus s. str. (with 17 species) and Mesocyprinus (with 5 species). Typical taxon on first subgenus Cyprinus (C.) carpio evaluate as a polytypical (with 4 subspecies). From 17 species of subgenus Cyprinus are 8 endemics only in Chinese province Yunnan (=Jünan), 1 species (C. qionghaiensis) province Sechwan, 1 species (C. acutidorsalis) on island Hainan, 5 species in northern as far as middle Vietnam and 1 species (C. intha) in Burma. Geographical distribution of 4 subspecies (C. carpio) is conformable with former views (Kirpichnikov 1967) and number of 2 - 3 domestication centres (Baruš et al. 2002). In subgenus Mesocyprinus registered species are Chinese faunistic elements with C. multitaeniata, that the was ascertained also in northern Vietnam.
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