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Jak i dlaczego badamy tempo wzrostu ryb? Aspekt praktyczny: Czy wymiar ochronny brzany Barbus barbus wyznaczono w Polsce prawidłowo?

Klich M.

Science, Technology and Innovation

2017

Vol. 1, no. 1

53--57

Na podstawie rybich łusek możemy określić wiek ryby, a także tempo wzrostu osobnika od urodzenia aż do chwili złowienia. W pracy przedstawiono metody oznaczania tempa wzrostu ryb oraz przykład praktycznego ich zastosowania do ustalania wymiaru ochronnego ryb, na przykładzie ustalonego w Polsce wymiaru dla brzany. Porównano dostępne dane dotyczące tempa wzrostu brzany z polskich rzek na podstawie 12 badań terenowych wykonanych w latach 1948–2004. Tempo wzrostu brzany w różnych środowiskach jest zmienne. Wzrost brzan w dużym stopniu zależy od wielkości rzeki i termiki. Wyniki te porównano z wiekiem dojrzewania brzany. Wyznaczony wymiar ochronny dla brzany wynoszący 40 cm jest prawidłowy. Wszystkie populacje brzany mogą przystąpić do tarła co najmniej jeden raz, zanim osiągną wymiar ochronny. Większość populacji może przystąpić do tarła co najmniej dwa lub trzy razy.

Based on fish scales, we can determine the age of fish, as well as the rate of growth of the individual from birth until the time of capture. The paper presents a method for determining the rate of growth of fish and the example of their practical application to determine the protective size limit of fish, on the example of barbel in Poland. The available data on the growth rate of barbel in Polish rivers, based on 12 field surveys carried out in 1948–2004 was compared. The growth rate of barbel in different habitats is variable. Barbel growth depends on the size of the river and thermal conditions. The results were compared with maturation age of barbel. Protective size limit definited for barbel, which is 40 cm, is correct. All populations of barbel can reproduce at least once before they reach the preservative size. Most of the populations may reproduce at least two or three times.

Stream habitat conditions and fish fauna within the occurrence range of Wałecki barbel, Barbus cyclolepis waleckii Rolik, 1970 (Teleostei: Cyprinidae) in Polish part of the Carpathian Mts

Amirowicz A., Kukuła K.

Polish Journal of Ecology

2005

Vol. 53, nr 4

503-522

Existing data on Wałecki barbel are very scarce and need a complement to the quantitative description of its habitat conditions. This fish is a subspecies of the Pontic species B. cyclolepis Heckel which occurs in some coastal rivers of the Black Sea or, as evidenced by some results of studies on mitochondrial DNA, it is a hybrid originating from natural crossing between the common barbel Barbus barbus (L.) and spotted barbel B. carpathicus Kotlik, Tsigenopoulos, Rab et Berrebi. Until now the Wałecki barbel was reported from 26 sites in the river basins of the Upper Vistula and the Dniester in SE Poland (49°09'-49°49' N, 21°28'-22°50' E, altitude 200-590 m). Seventeen of these sites were studied in autumn 2002 and summer 2003 to collect data on habitat parameters of stream channels. The main characteristics of their morphology (i.e. length, width, depth, and gradient) were calculated on the basis of a set of field measurements. Current velocity was measured using float method. The composition of bottom substratum was estimated using a simple scale based on Wentworth scale. Additionally, two biotic characters were included, i.e. the occurrence of macroscopic aquatic vegetation and the species composition of fish community. According to the obtained results the habitat conditions appropriate for Wałecki barbel may be defined as follows: 1) The stream should be medium-sized, at least 10-m or better 20-m wide. 2) The mean channel depth should exceed 20 cm, while the maximum depth should be greater than 50 cm. The channel morphology with the zone of medium depth (i.e. that extending over the half of bottom) in range between at least 15 and 40 cm seems to be favorable. 3) The mean stream velocity of 0.30 m s-1 or more is desired. It seems that the zone of fast current (0.50-1.00 m s-1) sharing a considerable portion of the channel is an important habitat feature. 4) Most of the bottom area should be covered by medium-sized particles (2-200 mm) with the mode within range of fine pebbles (20.50 mm). 5) In general, the stream should be rather oligotrophic than eutrophic with poorly developed macroscopic algae and the absence of vascular plants, and with flow fluctuations periodically disturbing structure of bottom substratum. 6) The abundant occurrence of spotted barbel, especially within lower part of its distribution area and in the zone of its co-occurrence with common barbel may be regarded as a good indicator of the stream habitat appropriate for Wałecki barbel. 7) Other frequent and abundant species accompanying Wałecki barbel are minnow Phoxinus phoxinus (L.), stone loach Barbatula barbatula (L.), chub Leuciscus cephalus (L.) and schneider Alburnoides bipunctatus (Bloch).