"Estuaries such as Long Island Sound are among the most valuable ecosystems in the world. The Sound supports diverse marine life, including most of the fish and shellfish we value as food ..."

– Connecticut Sea Grant

Conservation & Research

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Long Island Sound Fun Fact

Long Island Sound is 113 miles long, 21 miles wide (at its widest) and holds about 18 trillion gallons of water. Its average depth is 63 feet – which is just a little deeper than the height of our IMAX screen! Can you fathom that?!

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Common Name: Bluefish

Latin Name: Pomatomus saltatrix

Size/weight: Rarely seen larger than 20 pounds and 40 inches long.

Range: Western Atlantic populations range from Canada in the north to Florida and the Gulf of Mexico in the south (depending on season).

Habitat:  Adults inhabit coastal waters and are, at times, found in estuaries, harbors and off sandy beaches.

Diet: The bluefish’s diet includes squid, crabs, butterfish, menhaden, shad, herring, hake and smaller bluefish.  Bluefish are known as very aggressive fish and will often leave partially eaten or maimed prey behind.

Predators:  Sharks, tuna, striped bass, swordfish and humans.

Description:  Actually more green than blue, bluefish have strong, streamlined bodies and sharp, conical teeth.

Conservation Note:  Many fisheries managers believe that bluefish are being over-fished; populations may be on the brink of decline. However, Seafood Watch still lists bluefish as a Good Alternative, but consumers should limit consumption due to concerns about mercury or other contaminants.

See them seasonally in the Sea Turtle and the Ocean Beyond the Sound exhibits »

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Common Name: Atlantic cod

Latin Name: Gadus morhua

Size/weight: Up to 51 inches long and 77 pounds.

Range:  Both sides of the North Atlantic, on our side from Greenland to Cape Hatteras.

Habitat: Near the bottom of the water column in areas range from near shore to the edge of the continental shelf.

Diet: Cod are omnivorous, feeding on a wide variety of fish and invertebrates.

Predators: Humans, larger fish.

Description: Greenish, brown or grey dorsally, lighter shading ventrally.  Prominent barbel on chin.  Spots on back and sides.  Three dorsal fins and two anal fins.

Conservation Note:  Although fishing for cod was once a dominant part of the New England economy, in recent decades overfishing has severely depleted cod stocks. Thus, Seafood Watch lists Atlantic cod as a seafood to Avoid, except for cod obtained through hook-and-line fishing in the Gulf of Maine.

See them in "Go Fish!" exhibit »

cownose ray

Common Name: Cownose ray

Latin Name: Rhinoptera bonasus

Size/weight:  Up to 45 inches wide (wing tip to wing tip) and 50 pounds.

Range:  Massachusetts to Brazil

Habitat:  Sandy, soft bottom areas.

Diet: Clams, oysters and bottom-dwelling invertebrates.

Predators:  Sharks are the cownose ray’s main predators.  Humans; disc-shaped cutouts of ray wings are sometimes passed off as scallop.  Cownose rays are also sometimes cut up as bait for other fish.

Description:  Grey on top and white on bottom, cownose rays have broad wings, a long thin tail, and a notched head that some say resembles a cow’s muzzle (hence the name “cownose” ray).  Sharp, venomous spine (stinger) at the base of the tail.  A relative of sharks and skates, the cownose ray’s skeleton is made up of cartilage, not bones.

Conservation Note:  Not listed as endangered or vulnerable.

See them in the Shark & Ray Touch Pool »

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Common Name: American eel

Latin Name: Anguilla rostrata

Size/weight:  Females average 2 to 3 feet but may grow to 5 to 6 feet long. Males are generally half as big.

Range: American eels range from Greenland to South America, occurring in all major streams along the Atlantic coastline. The females migrate far inland, and have been documented in nearly all states east of the Rocky Mountains. This is possible because eels are able to live out of water for short periods of time. Their ability to slither up a moist slope allows them to circumnavigate major obstructions (e.g. dams and waterfalls) along their routes.

Habitat: Varies by life stage. See “Description” below.

Diet:  insects, smaller fish, fish eggs, crustaceans, worms, frogs.

Predators:  At sea: fish, birds. In inland waters: fish, turtles, birds, raccoons.

Description:  This is a fish – and eels are fish, by the way – that lives a life of several amazing metamorphisms that take it from sea water to fresh water and then back out to the salty ocean again. (That’s something few fish can do.)

An eel’s life stages are:


• “leaf fish” – These larvae look sort of like a clear flat willow leaf. Hatching in the Atlantic’s Sargasso Sea (SE of Bermuda), they ride the Gulf Stream currents for about a year.


• “glass eel” – Nearing the East Coast, leaf fish morph into the familiar eel shape. Tiny glass eels are still transparent but can now actively swim toward land.


• “elver” – Entering estuaries, they take on a brownish pigment.


• “yellow eel” – As elvers feed and grow, they turn olive-green with a yellow underside. They’ll stay in this adult stage for 5 to 20 years. Females swim upstream into fresh water and may even wriggle across land to ponds and lakes. Males tend to stay in more brackish waters.


• “silver eel” – In the fall, yellow eels that are ready to reproduce will stop eating, take on a silvery hue and their digestive systems shrink away to make room for new reproductive organs. Fueled only by their fat reserves, they swim back out to the Sargasso Sea to mate, lay eggs and die.


Conservation Note: Eel “landings” peaked in the late 1970s and early 1980s when record quantities of eels were caught and shipped to Asia, where folks have a taste for juvenile eels called elvers. But we caught too many eels too quickly. The number of eels harvested since then has dropped dramatically.

According to estimates from the International Council for Exploration of the Seas (ICES), the “recruitment level” (that is, the baby eels produced each year) is only 1 percent of what it was before the 1980s. Populations may be at record-low levels. In 2000, the Atlantic States Marine Fisheries Commission (ASMFC) issued an eel management plan. As eel “landings” continued to decline, the commission approved further protections in 2004. The U.S. Fish & Wildlife Service is reviewing whether eels need protection as a threatened or endangered species.

Besides overfishing, eel issues identified by the ASMFC include:
• dams have blocked eels from their migrations up rivers and streams.
• climate change may raise sea levels, which could affect the Sargasso Sea, a huge area south of Bermuda that is the American eel’s only mating spot/hatchery.
• climate change also could alter the Gulf Stream, hindering the migration of glass eels toward land.
• pollutants collect in eels’ fat reserves. That’s bad news for both the eels and anyone who eats them.

Although it may be hard to rally public support around an animal that is slimy and snake-like, things are being done to help eels. It’s now illegal to ship eels into or out of Europe. In the U.S., recent changes in size regulations have eliminated the elvers fishery in all states except Maine and Florida. And in Connecticut, the U.S. Fish & Wildlife Service, the Nature Conservancy, municipal conservation groups and the Aquarion Water Co., which supplies water to 39 cities and towns, all have been working on ways to help eels get around dams.

See them in their own exhibit in the Rivers to the Sound watershed gallery.

fiddler crab

Common Name: Atlantic marsh fiddler crab

Latin Name:  (Uca pugnax)

Size/weight: A small crab whose body (or carapace) is about 1 inch across. Males are slightly larger than females and have a blue spot on the top center.

Range:  Cape Cod down to northern Florida. This is the most common species of fiddler crab on the U.S. East Coast.

Habitat: in the intertidal mud of salt marshes. The crabs dig burrows, which they use for resting, mating, safety and hibernating. (They are known to roll up a ball of mud to plug their burrow hole at high tide.)

Diet:  They eat the mud too – well, they eat the tiny bits of fungus, algae, microbes, decaying plant & animal matter, and other organisms in the mud. What they don’t digest is deposited back as little mud balls.

Predators: Herons, gulls and other birds; raccoons; blue crabs; and other marsh predators.

Description:  Olive-brown in color. Dark banded walking legs. Slender eye stalks. Fiddler crabs are easily identified by the males, which have one ridiculously large yellowish claw – an adaptation that developed to help them attract females. A bigger claw gets the girl. The large claw, called the chela, can be either the male’s left or right. Also, males have a blue spot on the top center of their carapace.

Note:  Because all their digging helps to aerate the marsh, fiddler crabs are great for a marsh’s health.

Why are they called fiddler crabs? When a male feeds, the back-and-forth movement of its small claw (from the ground to its mouth) near its large claw resembles the motion of someone moving a bow across a fiddle.

Fiddler crabs are very skittish and retreat quickly to their marsh burrows. If you don’t want to go marsh-muckin’ in search of fiddler crabs, you can find them in The Maritime Aquarium's Salt Marsh Gallery.