Summer flounder
A predatory flatfish of the US Atlantic coast.
The summer flounder is a marine flatfish found in the western Atlantic from Nova Scotia to Florida. It supports major commercial and recreational fisheries in the northeast United States, where it is known as fluke.
- Has 5 to 14 eye-like spots on its body
- Can change colour to match the sea floor
- Supports major recreational and commercial fisheries
- Lives up to 20 years in the wild
- Migrates from deep ocean to inshore bays
What it is
This marine flatfish has a body flattened from side to side. Its upper side features five to fourteen eye-like spots. The teeth are sharp on both jaws. Adults usually measure between fifteen and twenty inches long. They can weigh up to twenty-six pounds, though most are much lighter. Females tend to be larger and older than males. The fish belongs to the left-eye flounder group.
Where it lives
Its range extends along the western Atlantic coast. Populations live from Nova Scotia down to Florida. It is most common in coastal and shelf waters off the northeast United States. In southern areas, it may mix with the southern flounder. That relative lacks the distinctive eye-like spots. The fish moves into bays, inlets, and estuaries during warmer months.
How it lives
Adults are aggressive predators that eat other fish. Their diet includes sand lance, menhaden, and squid. They also consume shrimp and crabs. They often lie buried in sand or mud with only their heads exposed. This ambush tactic helps them catch prey. They can swim rapidly over short distances. They possess dynamic camouflage abilities. They change colour and pattern to match the sea floor precisely.
Breeding and life cycle
Spawning takes place in deep ocean waters. This occurs during the spring months. After spawning, the fish move into inshore areas. They stay in beaches, creeks, and canals until autumn. Sexual maturity is reached at two years of age. The species can live for up to two decades. Female specimens have been observed living up to seventeen years.
Fish and people
It is a prized food fish with firm white flesh. Commercial fleets catch it using trawling methods. Recreational anglers target it from boats or shore. They use live bait, lures, or jigs. The species supports many local businesses. These include charter boats and tackle shops. Management involves federal and state agencies. Regulations on size and catch limits vary by state.
Status and threats
Debates exist regarding population declines. Overfishing is a primary concern for managers. The species is central to fisheries management laws. The Mid-Atlantic Fishery Management Council oversees its harvest. They work with other commissions to set rules. These regulations aim to sustain the fishery. Concerns have influenced national fishing legislation.
Questions people ask about Summer flounder
What is the difference between summer flounder and southern flounder?
The summer flounder has five to fourteen eye-like spots on its body. The southern flounder lacks these spots. They may mix in southern waters, causing confusion for anglers and biologists identifying the catch.
Why is the summer flounder called fluke?
Fluke is the common name used for this species in the northeast United States. It refers to the same fish, Paralichthys dentatus. The name is widely used by recreational anglers and commercial fishermen in that region.
How does the summer flounder catch its prey?
It buries itself in sandy or muddy bottoms with only its head exposed. It ambushes passing fish, squid, and crustaceans. It can also swim rapidly to chase prey actively at mid-depths or near the surface.
Good reading and sources
- Summer flounder on WikipediaEncyclopedia
- More photos on Wikimedia CommonsPhotos
- Wikidata recordOpen data
The facts on this page come from the Wikipedia article "Summer flounder", written by its contributors and used under the CC BY-SA 4.0 licence, and from its Wikidata record (CC0). EveryFish rewrote the text in its own words, with AI assistance, and compares every page with the article to make sure no passage is copied. It may be reused under the same CC BY-SA 4.0 licence with a link back.
It may contain mistakes, and figures change over time. Nothing here is investment or buying advice. If something is wrong, tell us. Last refreshed 2026-11-15.
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