During breeding season,Fundulus majalismales grow contact organs and aquire a brighter coloration. A female has one ovary. A greater number of eggs are laid during spring tides. This semilunar cycle is especially noticable late in the spawning season and is most pronounced in the souther populations. Low food densities ultimately limit egg production as witnessed in crowded populations with insufficient food resource availability. The spawning season near the Cheasapeake Bay is from April through September. After their first year, striped killifish males are smaller than their female counterparts.

Fundulus majalis feed on substratum material such as clams and annelid worms giving them a larger niche breadth than the mummichog (another killifish with similar eco-morphology).

(Abraham, Barbara. Species Profiles: Life Histories and Environmental requirements of Coastal Fishes and Invertebrates: Mummichog and Striped Killifish. U.S. Fish and Wildlife Service, 1985)

(Steele, CW. Competition, Niche Breadth and Niche Overlap in Two Sympatric Estuarine Killifish: A test of ecological theory. Second Annual Marine and Estuarine Shallow Water Science and Managament conference, US EPA 1995