They reach sexual maturity at the age of two years and have normal lifespans of four to five years. These fish like to be with others of their kind. While they can be left on their own, they would much prefer to be in schools. When these fish spawn, they don't necessarily find only one mate. The males seem to breed with as many females as they want.
Males generally are ready to spawn a few weeks before the females are each year.
Breeding generally takes place in the spring. The fish don't build nests. They simply lay about 20,000 to 50,000 eggs per female and let the young care for themselves. Smelt prefer to eat other fish. And believe it or not, the adult smelts are known to eat young smelts.