Abdoli, 2005



Citation


No detailed citation.

Associated characteristics


Species Development state Trait Primary Data Secondary Data
Cottus gobio Spawning conditions Spawning substrate All dominated by coarse substrata, mainly cobbles and large stones Lithophils
Cottus gobio Spawning conditions Spawning temperature 7-8 [5-12] 7.5 °C
Cottus gobio Spawning conditions Spawning period duration Occur over a period of about 1 month 1.0 weeks
Cottus gobio Spawning conditions Spawning water type Tributaries, reaches with relatively steep river slope No category
Cottus gobio Spawning conditions Spawning depth The water depths were <40 cm at the end of the low flow period 40.0 m
Cottus gobio Female Relative fecundity Mean absolute fecundity range from 184 ±7 [At age 2 and size 72 +/1, about 3 g, and 609 ± 47 [At age 6 and size 121 ±2 and about 30 g] 184.0 thousand eggs/kg
Cottus gobio Spawning conditions Spawning migration distance As bullhead are well known to be territorial fish with reduced migratory activity No data
Cottus gobio Female Oocyte development Just before spawning, the egg size distribution per site of all sampled gravid females showed a single mode Synchronous
Cottus gobio Egg Oocyte diameter Means between age range from 1.7-2.2, total range from 1.31 to 2.39 [egg-diameter of ripening female] 1.95 mm
Cottus gobio Female Absolute fecundity 69 to 896 eggs per female 69.0 thousand eggs
Cottus gobio Spawning conditions Spawning season Females spawned in April or early in all sites ['April']
Cottus gobio Female Weight at sexual maturity Among actively reproducing female, the smallest gravid female was 2.3 g, whereas the maximum weight was 31.7 g 2.3 kg
Cottus gobio Female Length at sexual maturity Among actively reproducing female, the smallest gravid female was 5.7 cm and 13.4 cm 5.7 cm
Cottus gobio Female Age at sexual maturity Among actively reproducing female, the smallest gravid female was 2 years and oldest 7 2.0 year
Cottus gobio Spawning conditions Spawning release Females laid all their eggs during the same period [Producing only one single batch of eggs per year] Yet, Fox also found that bullhead in less productive streams lay only one batch of eggs annually but in highly productive streams may lay up to four batches of eggs Ambiguous
Cottus gobio Spawning conditions Parity Actively reproducting female range from 2 to 7 years No category