Fish reproduction

thumb|Collecting Chinook salmon milt at a [[USFWS hatchery]]

young fish

thumb|right|190px|A female Cyphotilapia frontosa mouthbrooding fry which can be seen looking out from her mouth Mouthbrooding, also known as oral incubation and buccal incubation, is the care given by some groups of animals to their offspring by holding them in the mouth of the parent for extended periods of time. Although mouthbrooding is performed by a variety of different animals, such as Darwin's frog, fish are by far the most diverse mouthbrooders. Mouthbrooding has evolved independently in several different families of fish.

nest built by some fish- and frog species to contain their eggs

thumb|upright=1.35| ---- Fish produce many eggs, typically about 1mm across, and usually release them into the open water column

natural collagen casing found encompassing some aquatic lifeforms' fertilized eggs

reproductive physiology of fishes