New York Natural Heritage Program
Swamp Darter
Etheostoma fusiforme (Girard, 1854)
Ray-finned Fishes

Identifying Characteristics [-]
The swamp darter is a small fish rarely reaching over five centimeters in length. Its body is slender and light brown-olive in color, with the ventral side being lighter in color. There is a series of short bars on the side of the body that are positioned vertically on the anterior section, square in the middle section, and horizontally on the posterior section of the fish. The base of the tail fin has three spots in a vertical row. The lateral line arches high near the anterior part of the body and ends below the spiny dorsal fin. The fins are clear and lightly speckled. The pelvic fin is pointed, the pectoral fins are paddle-shaped, and the tail is square-shaped. The head is blunt and the eyes are set high on the head with a vertical bar underneath. A dark band runs around the snout. During the breeding season, the males develop tubercles on the pelvic and anal fin rays and a dark blotch between the first four spines of the anterior dorsal fin (Schmidt 1983; Smith 1985).

Characters Most Useful for Identification [-]
The high arch of the lateral line ending below the spiny dorsal fin and tubercles on the pectoral and anal fins of breeding males are characteristics that can be used to distinguish this species from other darters (Smith 1985).

Best Life Stage for Proper Identification [-]
Adults, especially males during spawning season, are the best life stage for identification.

Behavior [-]
Swamp darters rarely live through their second summer. They mature after their first summer. Spawning generally begins in April. Males swim up to the females and beat their pelvic fins. If the female is ready to spawn, they move up to the surface of the water into aquatic vegetation and swim side by side. The female vibrates her body while depositing eggs singularly into the vegetation while the male fertilizes them (Smith 1985). The eggs hatch in about 10 days and the fry are pelagic throughout the water column for about a month, after which they then settle down to life along the bottom (Schmidt 1983).

Diet [-]
The swamp darter feeds on midge larvae, Daphnia, and other small copepods, amphipods, and aquatic insects (Schmidt 1983; Smith 1985; Carlson 1998).
Swamp Darter Images
click to enlarge
The Best Time to See
Swamp darters can be observed year-round in the coastal plain ponds found along the Peconic River on eastern Long Island. Spawning typically begins in April and lasts until late May (Smith 1985).
J F M A M J J A S O N D
Active Reproducing
The time of year you would expect to find Swamp Darter active (blue shading) and reproducing (orange shading) in New York.
Similar Species
  • Iowa Darter (Etheostoma exile)
    Iowa and swamp darters are very similar except that during the breeding season, male Iowa darters become brightly colored and do not develop breeding tubercles. In New York, Iowa darters are found in the Lake Ontario watershed whereas swamp darters are confined to eastern Long Island (Smith 1985).