Markus, 1934



Citation


Markus, H.C. (1934) Life history of the blackhead minnow (Pimephales promelas). Copeia, pp. 116-122

Associated characteristics


Species Development state Trait Primary Data Secondary Data
Pimephales promelas Spawning conditions Mating system It was found that more than one female deposits eggs on the same nest cared for by a single male No category
Pimephales promelas Spawning conditions Nycthemeral period of oviposition Eggs were always deposited during the night Night
Pimephales promelas Spawning conditions Parental care The male performs three important functions when caring for the eggs during the incubation period. One is protection. Second, his constant movement underneath the eggs which keeps the water continually agitated. The third funtion is keeping the nest free from sediment that may be deposited from the water. No category
Pimephales promelas Spawning conditions Spawning substrate Nests may be found under rocks, timber, concrete, metal or tile if there is enough space underneath the object for activity of male Lithophils
Pimephales promelas Spawning conditions Spawning site preparation It seems evident that the male chooses the location of a nest for he is often seen wandering about for hours, aournd a suitable place, where eggs were found later. No category
Pimephales promelas Spawning conditions Spawning temperature Water temperature was 64°F, i.e. 17.8°C 64.0 °C
Pimephales promelas Spawning conditions Spawning period duration From May 5th to July 23rd, the spawning period of an individual female is about two months during the spawning season 5.0 weeks
Pimephales promelas Spawning conditions Spawning water type Ponds Stagnant water
Pimephales promelas Male Male sexual dimorphism Secondary sex characters were noted on the males approximatively thrity days before the first eggs were deposited, thus making it easy to distinguish males from females. The appereance of pearl organs or tubercles on the head and the coloration constitute the most evident secondary sexual characters. The secondary sexual characters began to fade immediatly after the close of the spawing period and by August 27th they were very faint and nearly obliterated. Absent
Pimephales promelas Egg Incubation time About 5 days at 61-77°F 69.0 days
Pimephales promelas Female Age at sexual maturity As low as 2-3 months for male and female 2.5 years
Pimephales promelas Egg Degree-days for incubation About 5 days at 61-77°F 69.0 °C * day
Pimephales promelas Egg Temperature for incubation About 5 days at 61-77°F, i.e. 16-25°C 20.5 °C
Pimephales promelas Egg Egg size after water-hardening The eggs averaged 1.15 mm in diameter 1.15 mm
Pimephales promelas Egg Egg Buoyancy Lay their eggs on the under side of objects that lie horizontal to or at an angle with the surface of water No category
Pimephales promelas Spawning conditions Spawning season In the spring of 1931 the first eggs appeared May 16th and in 1932 on May 5th ['April', 'May', 'June']
Pimephales promelas Larvae Temperature during larval development 25-26 [About 70-80°F [A.M] and 80-90°F [P.M.]] 25.5 °C
Pimephales promelas Larvae Initial larval size 4.75 4.75 mm
Pimephales promelas Female Age at sexual maturity As low as 2-3 months for male and female 2.5 year
Pimephales promelas Spawning conditions Parity The death rate of the adult minnows is very high after the spring spawning period Semelparous