The fathead minnow has an alarm system that releases an element called Schreckstoff when particular cells are injured in an attack. Then, this launched material is identified by the killer fish which after that will certainly hide or dart away. This system assists fathead minnows acknowledge possible predators. The fathead's main predator is the northern pike, and this chemical acknowledgment capability assists the minnow identify its killers.
The spawning season of the fathead minnow flies June via July, with some spawning as early as mid-May, and including very early August. They like a temperature level array of 50 - 70 levels Fahrenheit, and also spawing happens in temperature levels around 64 degrees Fahrenheit. The male looks after eggs that the female down payments in a nest. Generally, a male fathead minnow will take over a nest website that is presently being used. It decides on websites that currently include eggs, and also the more eggs in the nest, the more likely the existing man will be challenged by a brand-new male fathead minnow. This sort of actions is called allopathernal treatment, where one male displaces the other male. Males aerate the eggs, they eliminate unhealthy eggs, and they defend eggs from killers such as crayfish. By "switching over out" the males, it permits greater survival of the eggs, as the brand-new men that take over are "fresher" and more in shape perhaps, to advance the task of protecting the eggs. Each male minnow shields the website for three to five weeks, permitting a "changing of the guard". The eggs hatch in roughly five days.