Atlantic silverside
The Atlantic silverside (Menidia menidia) is a small, omnivorous fish typically growing up to six inches (15 centimeters) in length. Recognizable by their long, straight-edged anal fins and distinctive silvery band along their sides, these fish inhabit a range of environments, including brackish, fresh, and saltwater marshes, as well as sandy seashores from the Gulf of St. Lawrence to northern Florida. Their bodies are streamlined, equipped with fins that aid in swimming and balancing in the water. Atlantic silversides breathe by taking in water through their mouths and extracting oxygen via gills, a process different from that of land-dwelling animals.
Spawning occurs between May and July, during which females release eggs that males fertilize in the water. Young silversides, known as fry, start off as timid and solitary but gradually learn to school in larger groups as they mature. While they face threats from larger predators and are sometimes caught for bait or consumed by humans, their conservation status is currently stable. Atlantic silversides have a lifespan of about two years, contributing to their ecological role in aquatic ecosystems.
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Atlantic silverside
Atlantic silversides are noted for their long, straight-edged anal, or belly, fins. Within the grouping of silversides, it is important to note tiny differences, such as fin formation, because these are often the only ways to tell one species from another.
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Atheriniformes
Family: Atherinopsidae
Genus: Menidia
Species: Menidia
Atlantic silversides are found in brackish, fresh, saltwater marshes, and along sandy seashores and in the mouths of inlets throughout the waters of the western Atlantic. They inhabit areas from the Gulf of St. Lawrence along the eastern seaboard of Canada to the waters around northern Florida.
As omnivorous, or meat-and-plant eating, fish, Atlantic silversides live on a diet of aquatic, or water-living, plants and animals.
Atlantic silversides generally grow to be about six inches (fifteen centimeters) long. Transparent, or clear, greenish scales cover their backs, while their rounded bellies are covered with paler scales. At the point on their sides at which the greenish scales from above meet the pale scales from below, there runs a long, thin, silvery band from their pectoral, or side, fins to their caudal, or tail, fins. These are the bands for which silversides are named. Atlantic silversides have thin, streamlined bodies with many fins which help them to swim. Their pectoral and pelvic fins help them to paddle through the water, while their two, short, spiny dorsal, or back, fins and their anal, or belly, fins help them to maintain their balance. Atlantic silversides are known for their long, straight-edged anal fins. They are one of the distinctive marks of Atlantic silversides. The large caudal fins of Atlantic silversides work much like the propellers of boats. They move through the water propelling the fish as they go.
Unlike humans, who can breathe oxygen from the air, most fish do not have lungs with which to process oxygen in this way. Atlantic silversides get the oxygen they need from the water in which they live. They take water into their mouths, keep the oxygen they need, and release the waste chemicals through the gills on the sides of their bodies.
The mating season for Atlantic silversides is May to July. Spawning between Atlantic silversides begins when the females release their eggs into the water. The males swim over these eggs and release their fertilizing substance. This process of releasing and fertilizing eggs is known as spawning. Young Atlantic silversides, which are called fry, are very small, shy, antisocial creatures. They often dart away from their many brothers and sisters. As they grow, they become increasingly comfortable with large groups. Eventually, when they are about 3/4 of an inch (about one centimeter) long, they begin gathering into large schools, or groups, like adult Atlantic silversides.
Like other silversides, larger sea creatures and humans often threaten Atlantic silversides. They are sometimes used by anglers as bait to catch larger fish. They are also deep-fried for human consumption. Their conservation status is stable.
The life span of Atlantic silversides is two years.
Bibliography
“Atlantic Silverside.” Chesapeake Bay Program, 2024, www.chesapeakebay.net/discover/field-guide/entry/atlantic-silverside. Accessed 30 Mar. 2024.
New York Natural Heritage Program. “Menidia Menidia.” Online Conservation Guide, 4 Jan. 2008, www.fisheries.noaa.gov/species/giant-manta-ray/overview. Accessed 30 Mar. 2024
“Species: Menidia Menidia, Atlantic Silverside.” Smithsonian Tropical Research Institute, 9 Feb. 2024, www.biogeodb.stri.si.edu/caribbean/en/thefishes/species/3250. Accessed 30 Mar. 2024.