Tomlinson and Perrow, 2003


Tomlinson, M.L. and Perrow, M.R. (2003) Ecology of the bullhead., pp.

Associated characteristics

Species Development state Trait Primary Data Secondary Data
Cottus gobio Egg Egg size after water-hardening 2-2.5 2.25 mm
Cottus gobio Egg Egg adhesiveness Adhere to the underside of the stone Adhesive
Cottus gobio Egg Incubation time 20-30 days 25.0 days
Cottus gobio Larvae Initial larval size 6-7 6.5 mm
Cottus gobio Larvae Larvae behaviour The young absorb their yolk sac after which, as fry (9 mm in length) they are ready to disperse Demersal
Cottus gobio Larvae Full yolk-sac resorption Large yolk-sac absorbed in 10 days 10.0 °C * day
Cottus gobio Male Male sexual dimorphism Males are deadily distinguished at spawning time by their dark colouration, a cremy dorsal edge to the first dorsal fin, and protruding genial papillae Absent
Cottus gobio Spawning conditions Homing Fish are faithful to permanent shelter for many years; Bullhead developed a fixation for their "home" stone, selecting it above others even when it moved, although for a short time the fish occasionally returned to its stone's original location. This suggests bullheads may home effectively; a finding that was supported by a field experiment in which 87% of fish were found under the stone six days after initial capture. Present
Cottus gobio Spawning conditions Spawning season Spawn from February to June ['February', 'March', 'April', 'May', 'June']
Cottus gobio Spawning conditions Spawning site preparation The male excavates a nest under a suitable large stone to attract female No category
Cottus gobio Spawning conditions Mating system Some males may attract more than one female No category
Cottus gobio Spawning conditions Spawning release Typically once for females in upland streams, and up to four times in warmer, more productive lowland streams [Females adopt fractional reproduction in the latter, with successive batches of secondary oocytes developping into eggs, which the females then lays, perhaps with different partners] Multiple
Cottus gobio Spawning conditions Spawning release Females lays a batch of up to 400 eggs Multiple
Cottus gobio Spawning conditions Parental care The male defends the brood against egg predators, and manages the nest by fanning the eggs with his pectoral fins. Male parental care