Details
Fundulus heteroclitus
A small killifish of North American Atlantic salt marshes, famous for tolerating harsh tidal pools and estuaries.
Map: Ecoregions 2017 © RESOLVE (CC BY 4.0) · Natural Earth (PD)
Ranges from eastern Canada down the U.S. Atlantic coast in salt marshes, estuaries, tide pools, and brackish creeks with variable salinity and temperature.
The body is small and stout, brown to olive. Breeding males may show yellow and blue tones with stronger side bars.
Small groups move through shallow marsh channels and remain in tide pools at low tide, tolerating low oxygen and high salinity.
It is omnivorous, eating algae, detritus, small crustaceans, insects, and fish eggs as tides change feeding access.
Eggs are laid around marsh plants or shells on high tides. They can endure exposed periods and hatch with later tides.
Mummichogs are used in toxicology and spaceflight research, and they link marsh invertebrates to small predators and birds.
