Merck Manual

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Types of Fish Reproduction

Types of Fish Reproduction

Types of Egg Layers

Where Eggs Are Laid

Fertilization Method

Common Species

Mouthbrooders

In water, then collected in mouth once fertilized and held there until birth; some hold fry in mouth for up to a week after birth

Fertilized by spawning before being gathered in mouth

Freshwater cichlids, bettas, cardinal fish, gobies, blennies

Nest builders

A spot in substrate, a structure made of plant materials, bubble nest (foamy structure)

Spawning

Bass, bluegills, sticklebacks, gouramis, bettas

Egg scatterers

Sticky eggs: laid within a certain area under cover; nonsticky eggs: set adrift in open water

Male swims by and sprays semen, or milt, around the area

Cardinal tetras, tiger barbs, zebra danios, goldfish, koi

Egg depositors

Laid in one spot, usually substrate or glass

Male swims by and fertilizes eggs

Rainbow fish, killifish, dwarf cichlids, clownfish

Egg buriers

Buried in soft substrate

Male dives into substrate to fertilize eggs

Killifish, rare and endangered species in the wild