Striped killifish
The striped killifish (Fundulus majalis) is a notable species within the killifish family, known for its distinctive stripes and bars. Males typically display 15 to 20 black bars, while females possess fewer markings, with variations in pattern depending on their geographic location. These fish reach lengths of about six to seven inches and are characterized by their streamlined bodies and olive-green scales. Striped killifish are commonly found in the shallow waters of the Atlantic coast, from New Hampshire to northeastern Florida, as well as in the Gulf of Mexico, typically inhabiting sandy and muddy-bottomed environments.
As omnivores, striped killifish feed on a mix of plant and animal matter and are vital components of their ecosystems, serving as prey for larger fish and birds. Their mating season occurs from late spring to early summer, during which males become more vibrant to attract females. The spawning process involves females laying several clutches of eggs, resulting in about 50 eggs per clutch, which hatch after 10 to 12 days without parental care. While not currently considered threatened, some populations may face declines in certain regions. Overall, striped killifish play an important role in their habitats and contribute to the diversity of marine life along North America's coastal regions.
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Striped killifish
Both male and female striped killifish display the bars and stripes for which they are named. The males generally have between 15 and 20 black bars along their sides, while the females have only a few of these markings. In the waters of the Atlantic, the females have two to three black stripes, while in the Gulf of Mexico they are decorated with dark bars. This fish can be found on the eastern and southern coasts of North America.
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Cyprinodontiformes
Family: Fundulidae
Genus: Fundulus
Species: Majalis
Striped killifish are one of the largest members of the family Fundulidae within the grouping called killifish. They grow to a length of about six to seven inches (15 to 18 centimeters). In body shape, they resemble the mummichogs, another species of killifish, although they are not as stout as the mummichogs. Striped killifish have streamlined bodies with rounded bellies. Their backs are covered with olive-drab to brassy olive-green scales, while their bellies are decorated a paler olive. Male striped killifish have 15 to 20 black bars along their sides. The females do not have that many markings. The females which live in the waters of the Atlantic have two to three black stripes, while the females in the Gulf of Mexico have dark bars. Male striped killifish are generally about an inch (three centimeters) longer than the females.
Like other killifish, striped killifish move through the water with the help of their many fins. Their squared-off caudal, or tail, fins move from side to side to propel these fish through the water. Along their backs they each have a thin dorsal, or back, fin which helps give them their balance. On their bellies, striped killifish have more fins. Their anal and pelvic fins are located there. The anal fins work with the dorsal fins to help keep striped killifish balanced in the water, while the pelvic fins work together with the pectoral, or side, fins to paddle striped killifish through the water.
Since striped killifish need oxygen to survive and cannot take in oxygen through the air, they have to use the oxygen which is in the water. They take water into their mouths, use the oxygen they need, and release the waste chemicals through the gills on the sides of their bodies.
Striped killifish may be found in large schools, or groups, swimming through the shallow bays, estuaries, and coastal marshes along the Atlantic coast from New Hampshire to northeastern Florida and around the Gulf of Mexico. They often inhabit sand and sandy-mud-bottomed salt marshes.
Striped killifish are omnivorous. This means they feed on both plants and animals. Like other killifish, striped killifish are preyed upon by larger sea creatures, fish-eating birds, and mudpuppies.
Mating season for striped killifish lasts from late spring to early summer. As in other killifish, male striped killifish turn brighter during the breeding season. Their scales turn a deeper shade of brassy olive-green. The females lay a few large eggs at a time for the males to fertilize. This process of releasing and fertilizing eggs is known as spawning. Eventually each group of eggs, or clutch, may reach 50 eggs. Females may lay several clutches each year. The young killifish hatch after 10 to 12 days and are left with no parental care.
Striped killifish live between three and five years. They are not a threatened species, although their numbers may be declining in specific areas of their range.
Bibliography
Lee, John. “Striped Killifish Fundulus Majalis.” Chesapeake Bay Program, 2024, www.chesapeakebay.net/discover/field-guide/entry/striped-killifish. Accessed 3 May 2024.
Smithsonian Tropical Research Institute. “Shorefishes - The Fishes.” Shorefishes - The Fishes - Species, 2023, biogeodb.stri.si.edu/caribbean/en/thefishes/species/3264. Accessed 3 May 2024.