Growth of Five Spirlin (Alburnoides bipunctatus) Populations from the Croatian Rivers
Tomislav TREER, Dobrila HABEKOVIĆ, Ivica ANIČIĆ, Roman SAFNER, Marina PIRIA
Pages: 175-180
Summary
Age, growth and mortality were analysed for spirlin (riffle minnow), Alburnoides bipunctatus that was collected from the five rivers in Croatia. Growth in length was very similar at all locations, so the average growth curve for this species in Croatia can be expressed as:
Lt=15.2 (1-e-0,28(t+0,93))
A comparative growth index for the first five years of spirlin life was the lowest in the middle Korana river (98.0%) and the best in the middle part of the Dobra river (103.1%). All these indices are very close. The phi-primes also varied a little, resulting in the following average: ft= 4.24±0,11. Weight expressed positive allometric growth at four locations (b-value ranging from 3.10 to 3.56) and negative at only one (b=2,80). At the same location the total instantaneous mortality rate was the highest (z=1.14), while at other locations it ranged from 0.77 to 0.93. Spirlin is evidently subjected to great predation. Consequently, these results can help in comparing different water habitats.
Lt=15.2 (1-e-0,28(t+0,93))
A comparative growth index for the first five years of spirlin life was the lowest in the middle Korana river (98.0%) and the best in the middle part of the Dobra river (103.1%). All these indices are very close. The phi-primes also varied a little, resulting in the following average: ft= 4.24±0,11. Weight expressed positive allometric growth at four locations (b-value ranging from 3.10 to 3.56) and negative at only one (b=2,80). At the same location the total instantaneous mortality rate was the highest (z=1.14), while at other locations it ranged from 0.77 to 0.93. Spirlin is evidently subjected to great predation. Consequently, these results can help in comparing different water habitats.
Keywords
spirlin; riffle minnow; Alburnoides; growth; von Bertalanffy; Croatia
Full Text: PDF