Some added info:
In fathead minnows, maturity is reached in four to six months at a size of approximately 40 mm TL for females and 48 mm TL for males. Spawning occurs naturally from May through August (15EC to 32EC) in calm shallows of streams and along shorelines in ponds. Males select and prepare the nest site defending it from intruders and only allowing persistent females to enter and spawn. Nests are typically located on the undersurface of submerged stones or branches. Females spawn fractionally every 2 to 16 days producing up to 10,000 eggs in a three month breeding season (Gale and Buynak, 1982). Males protect eggs from predation and cannibalism and fan egg masses with caudal and dorsal fins to increase oxygen availability. The spongy nape pad, used for scrubbing the nest site, has taste buds capable of chemosensory assessment of egg condition and is believed to produce substances with fungicidal properties (Jenkins & Burkhead, 1994). Eggs hatch in 4 to 10 days depending on temperature(colder temperatures take longer). The combination of high fecundity and parental care stands in contrast to normal aspects of the r- and K-selection model (Jenkins & Burkhead, 1994).
