Lusk et al, 2005



Citation


Lusk, S. and Luskova, V. and Halacka, K. and Slechtova, V. and Slechta, V. (2005) Characteristics of the remnant Vimba vimba population in the upper part of the Dyje River. Folia Zool., pp. 389-404

Associated characteristics


Species Development state Trait Primary Data Secondary Data
Vimba vimba Egg Oocyte diameter Two size groups of eggs were found in gonads, the first of size 1.15-1.63 mm in stage "E", the second with size 0.4-0.6 mm in stage "C". The mean egg size was 1.33 mm (1.26-1.41 mm). We obtained 9500 eggs (mean diameter 1.51 mm) from the female with SL= 213mm (age 5 years), and 7400 eggs (mean diameter 1.46 mm) from the female with Sl= 188 mm(age 4 years) 1.39 mm
Vimba vimba Egg Egg size after water-hardening The mean egg size on the 3rd day of incubation reached 1.95 mm (1.90-2.05 mm). 1.97 mm
Vimba vimba Egg Egg adhesiveness Fertilized eggs were seperated using water-diluted milk and placed in 1.5 litre hatching jars. Non-Adhesive
Vimba vimba Egg Incubation time Hatching occurred on the 5th day within 6 hours after reaching 80-90 degree-days 85.0 days
Vimba vimba Egg Temperature for incubation Water flowing through the apparatus had a temperature of 15-16°C, rising at the end of incubation to 17°C 15.5 °C
Vimba vimba Egg Degree-days for incubation Hatching occurred on the 5th day within 6 hours after reaching 80-90 degree-days 85.0 °C * day
Vimba vimba Larvae Initial larval size Larvae hatched in the VII th development stage at a mean length of 4.7 mm, eyes without pigmentation and pectoral fins just beginning to form 4.7 mm
Vimba vimba Female Relative fecundity In eight females with mean SL=196.7 mm (188-213 mm) and mean weight 149.1 g (126-175 g), the relative fecundity varied between 133000 to 155000 eggs per kg of female weight (mean 133000 eggs per kg) 200.5 thousand eggs/kg
Vimba vimba Female Absolute fecundity In eight females with mean SL=196.7 mm (188-213 mm) and mean weight 149.1 g (126-175 g), the absolute fecundity varied between 15,600 and 23,100 eggs (mean 19,300 eggs) 200.5 thousand eggs
Vimba vimba Female Maximum GSI value The mean GSI in eight examined females amounted to 13.9% (12.1-17.3%) 14.7 percent
Vimba vimba Male Age at sexual maturity The youngest mature males in the spawning shoal in 1993 were four years old - 14 males and only one female (year class 1990). In 1995 seven mature males aged 3 years (year class 1992) and four mature females 4 years old (year class 1992) were found. Males generally matured one year-earlier than females. Analysis of the age structure of the spawning shoals sampled on 3 June, 1993 and 2 June, 1995 showed that they comprised mainly 4 to 6 year old fish, with a predominance in two year classes: four -and five -year old males comprising 91.97% of 83 individuals in 1993 and 82.30% of 96 individuals in 1995, whereas females consisted mainly of fishes in the age of five to six years in 1993 (=74.19% from 31 ind.) and four to six years in 1995 (=82.30% of 39 ind.) 1993.0 years
Vimba vimba Male Maximum GSI value Mean GSI in 14 males was 2.48% (1.68-3.38%) 2.53 percent
Vimba vimba Spawning conditions Spawning period duration The spawning of V. vimba in the studied locality occurred once each year according to our observations, and lasted 2-3 days; no other spawning sites were found in this part of the River Dyje. 2.5 weeks
Vimba vimba Spawning conditions Spawning temperature Conditions during the spawning: 19.1-20°C [Somewhat cloudy, in 1-3 June 1993], 19.3-19.8 [Sunshine, 2-3 June 1994], 19.0-20.2°C [Overcast, 28-30 May 1995], 19.8 [Overcast, 1-2 June 1996], 20.2 [Somewaht cloudy, 3-4 June 1997] 19.55 °C
Vimba vimba Spawning conditions Mating system The spawning behaviour and the course of spanwing was similar to those of the nase carp Chondrostoma nasus. The spawning ground was occupied by the shoal consisting of males, whereas females stayed downstream of the place. Ripe females came individually to the spawning site where the group of males joined them. The whole group of one female and several males moved upstream with simultaneous releasing of gametes. Males were found only sporadically away from the spawning place Polyandry
Vimba vimba Spawning conditions Spawning release According to our examination wimba has a single spawning per season in the studied population. According to other study, V. vimba in the basins of the Baltic and Black seas is a repeat spawner (2-3 batches) and it is therefore impossible to compare those results with ours Multiple
Vimba vimba Spawning conditions Parity The oldest individual found in our study was a female of 10 years and 300 mm Sl. One aged 9 years and three aged 8 years were also females. The oldest males (n=6) were 7 years old and there were 8 females of this age No category