Aquatic Life

The most common groups of aquatic animals in the Chesapeake are: Navigation

 

Bivalve- an aquatic mollusk that has a compressed body within a hinged shell


Atlantic Ribbed Mussel - Geukensia demissa

Identify Memussels in marsh bed

  • Grow to 2 to 4 inches in length
  • Glossy, ribbed shells
  • Vary in color from olive to yellowish-brown to black
  • Shell's interior is blue to silvery white

Find Me

  • Low, regularly flooded marshes and mud flats. We attach ourselves to marsh grass roots and other strong surfaces

I Like to Eat

  • We are filter feeders that filter algae out of the water during high tide.

Biologist's Note

  • During low tide, ribbed mussels close their shells, keeping in waste products that can be toxic to humans. For this reason, you should only collect mussels during high tide.

Cool Fact

  • The age of a ribbed mussel can be determined by counting the ribs on its shells.

Bay Scallop - Argopecten irradians

Identify Mescallop shells

  • Rounded, ribbed shell
  • Vary in color from gray to purple or reddish-brown
  • Shell's interior is white with purple around the edges
  • Pointed "ears" at the shell's edges
  • Short tentacles and 30 to 40 blue eyes around the edge of their shells
  • No "foot" to latch onto hard surfaces
  • Grow up to 3 inches in diameter

Find Me

  • Shallow waters along eelgrass beds; along the bottom, bot burried in the sand like other bivalves

I Like to Eat

  • We are filter feeders that filter plankton out of the water through our gills.

Biologist's Note

  • Each eye has a lens, retina, cornea and optic nerve, enabling the scallop to see movement and shadows.

Cool Fact

  • Scallops move by rapidly clapping their shells together, forcibly ejecting water from the cavity. This is different than most other bivalves, which use a foot to move.

Eastern Oyster - Crassostrea virginica

Identify Meoyster shells

  • Grow to 3 to 5 inches in length, up to 8 inches
  • Color varies from white to gray to tan
  • The top shell is flat
  • Bottom shell is cupped with a purple muscle scar on the inside

Find Me

  • Brackish and salty waters from 8 to 35 feet deep
  • Waterways with firm bottoms for attatching to

I Like to Eat

  • We are filter feeders that feed on plankton by pumping water through our gills.

Biologist's Note

  • An adult oyster can filter up to 50 gallons of water in one day.

Cool Fact

  • Historically, oysters were only eaten during months whose names contain an “R.” This is because oyster quality is poor right after they have spawned, and because oysters would spoil without refrigeration during warmer months.

Zebra Mussel - Dreissena polymorpha

Invasive

Identify MeZebra mussel shell

  • Grows to less than 1 inch
  • D-shaped or triangular shell
  • Color is dark brown and light stripes

Find Me

  • Still or slow moving freshwater lakes, rivers, streams, and reservoirs

I Like to Eat

  • We are filter feeders that feed on plankton and other particles by pumping water through a siphon.

Biologist's Note

  • Zebra mussels can cause environmental and economic harm, killing native freshwater mussels and disrupting aquatic ecosystems as well as clogging municipal pipes and damaging boats.
 

Shellfish- an aquatic shelled mollusk or crustacean that is edible (does not necessarily have a hinged shell)


Blue Crab - Callinectes sapidus

Identify Meblue crab

  • Dark green top
  • White bottom
  • Deep blue on top of claw
  • Carapace up to 9 inches
  • Female: red claw tips

Find Me

  • Bay grasses, like eelgrass and widgeon grass

I Like to Eat

  • Soft-shelled clams, fish, and other blue crabs

Biologist's Note

  • The world-famous Chesapeake Bay blue crab has long been a symbol of the Bay's bounty. In recent years, the blue crab catch has reaped more than $50 million annually.

Cool Fact

  • The scientific name, Callinectes sapidus, means "beautiful swimmer" in Latin.

Marsh Fiddler Crab - Uca pugnax

Identify MeFiddler crab on beach

  • Vary in color from tan to brown
  • Males have one claw that can grow to 1.5 to 2 inches long
  • The shell is squared with rounded rear edges
  • Male crabs have a royal blue spot on the center of the shell
  • The marsh fiddler crab is the smallest in the Bay region

Find Me

  • Marshes, beaches, and mud flats

I Like to Eat

  • Algae, bacteria, and decaying marsh plants

Biologist's Note

  • You can identify a fiddler crab species by examining its enlarged claw: the sand fiddler crab’s claw is smooth on the underside. If the claw is not smooth on the underside and had red joints, it is a red-jointed fiddler crab. Otherwise, it is a marsh fiddler crab.

Cool Fact

  • If a male loses its major claw, the remaining claw grows to the same size as the lost claw. The new claw that grows becomes the smaller claw.
  • The male’s enlarged major claw is not for fighting predators, but primarily to attract a mate and discourage rivals.

Horseshoe Crab - Limulus polyphemus

Identify Mehorseshoe crab on beach

  • Brownish-green high-domed body
  • Spiked tail
  • Five pairs of dark brown legs and gills on underside
  • Length: up to 2 feet

Find Me

  • Shallow and deep water (all bottom types) with various salinities

I Like to Eat

  • Tiny worms, clams, and dead fish

Biologist's Note

  • Horseshoe crab eggs are an important food for migratory birds as the birds journey north in spring.

Cool Fact

  • Horseshoe crabs have been on earth for over 350 million years; long before the dinosaurs arrived.

Knobbed Whelk - Busycon carica

Identify Mewhelk shell on beach

  • Whorled or spiral shell
  • Shell opening on right side
  • Shell color varies by geographic region: outer shell varies from grayish white to tan with inner shell from pale yellow to orange
  • Body of the snail is divided into head, abdomen, and foot
  • Two pairs of tentacles are located on its head
  • Adults measure 5 to 9 inches
  • Females grow larger than males

Find Me

  • Tidal estuaries; shallow waters, but can be found in depths up to 150 ft deep

I Like to Eat

  • Clams, oysters, mussels, and other bivalves

Biologist's Note

  • As an economic resource, knobbed whelks are fished for their meat and sold in the tourist trade as ornamentals.

Cool Fact

  • Knobbed whelks have been in existence for more than 30 million years.
 

Other Invertebrates - other aquatic creatures that lack a backbone


Common Grass Shrimp - Palaemonetes pugio

Identify MeGrass shrimp

  • Segmented, transparent body
  • Pointed "horn" that extends over its eyes
  • The first 2 pairs of walking legs have claws
  • Length: up to 1.5 inches

Find Me

  • Shallow waters among bay grass beds

I Like to Eat

  • Worms, algae, and tiny crustaceans

Biologist's Note

  • Grass shrimp are an important ecological indicator of human impacts on estuaries and other water bodies.

Cool Fact

  • The common grass shrimp is the most abundant of the four species of grass shrimp known to live in the Bay.

Jellyfish - Order: Semaeostomeae

Identify Mejellyfish swimming

  • Transparent, jelly-like body
  • Umbrells-shaped bell called a medusa
  • Tentacles with stinging cells hanging from the bell called nematocysts

Find Me

  • Brackish and salty waters; shallow and open waters and tidal rivers

I Like to Eat

  • Sea nettles and lion's mane jellyfish feed on fish, shrimp, and comb jellies

Biologist's Note

  • Jellyfish propel themselves through the water by rhythmically expanding and contracting their bells. However, they are not very good swimmers; jellyfish are mostly transported by wind and currents.

Cool Fact

  • Sea nettles are nearly 90 percent water.

Marsh Periwinkle - Littorina irrorata

Identify Memarsh periwinkeles on marsh grass

  • Grow to 1 inch in length
  • Spiraled, groved shell
  • Shell color varies from grayish-white to tan
  • Reddish-grown flecks appear on the spiral ridges of the shell

Find Me

  • Low, sheltered tidal marshes and wetlands

I Like to Eat

  • Algae and dead material

Biologist's Note

  • Marsh periwinkles are gastropods, a type of mollusk that includes whelks, snails and slugs.

Cool Fact

  • These snails are known to practice "fungiculture": by chewing holes in the cordgrass and spreading waste across the cuts, the marsh periwinkle can "farm" fungus, their preferred food.
 

Amphibians- cold-blooded vertebrate that start their life in a larval stage in water with gills to breathe, but then are terrestrial lung-breathing animals in adulthood.


Hellbender - Cryptobranchus Alleganiensis

Identify Mehellbender in fish tank

  • Length: 11.6 to 27 inches
  • Weight: 0.9 and 2.2 pounds
  • Dark brown or black with lighter bellies
  • Loose skin that creates folds along the body
  • Flat, broad heads and short noses
  • Short, stuby limbs

Find Me

  • Fully aquatic amphibians that live in freshwater streams
  • Prefer gravel stream bed to muddy stream bed

I Like to Eat

  • Crayfish

Biologist's Note

  • Hellbenders are the largest of any North American aquatic salamander.

Cool Fact

  • Common nicknames for the hellbender include “snot otter” and “lasagna lizard.”
  • The scientific name Cryptobranchus means “hidden gills.”

Northern Diamondback Terrapin - Malaclemys terrapin

Identify Meturtles swimming

  • Light brown shell with gray or black plates
  • Yellow to olive bottom
  • Mottled skin

Find Me

  • Brackish water areas, like tidal marshes and lagoons

I Like to Eat

  • Crabs and other snails, fish, insects, and some marsh plants

Biologist's Note

  • This species faces a number of threats, including destruction of coastal habitat, boat propellers, automobiles, and animals such as raccoons, muskrats, skunks, foxes, and crows that eat turtle eggs.

Cool Fact

  • Female terrapins grow about 9 inches long; males are usually only half as large.
 

Reptile- a vertebrate animal that has dry, scaly skin


Black Rat Snake - Elaphe obsolete obsoleta

Identify MeBlack rat snake

  • Length: 3.5 to 6 feet
  • Black, scaly body
  • White belly and chin
  • Wedge-shaped head

Find Me

  • One of the most ocmmon snakes found in suburban backyards; from rocky hills to farmland

I Like to Eat

  • Small rodents: mice, rats, moles, and chipmunks

Biologist's Note

  • Although they may strike if they feel threatened, black rat snakes are not venomous.

Cool Fact

  • These snakes are excellent climbers that are able to scale brick walls and tree trunks without any aid.

Copperhead - Agkistrodon contortrix

Venomous

Identify MeCopperhead on ground

  • Broad, unmarked, copper-colored head
  • Reddish-tan colored body
  • Underside is a pinkish color
  • Pupils are elliptical (indicator that it is venomous)
  • "Pit-viper" meaning that it has a heat-sensing pit located on its head between its eye and nostrils
  • Length: up to 3 feet

Find Me

  • Woodlands, along streams and creeks, rocky hills and fields

I Like to Eat

  • Mice, birds, snakes, amphbians, and insects

Biologist's Note

  • Young copperheads have yellow-tipped tails, which they use to attract small prey.

Cool Fact

  • Copperheads bite more people each year than any other snake species in the United States. But although copperheads are venomous, they are typically calm snakes that only bite if stepped on or otherwise threatened. If you see a copperhead, leave it alone! Allow it to continue on its way, undisturbed.
 

Fish-a cold-blooded, limbless animal with gills and fins that lives completely in water


American Eel - Anguilla rostrata

Identify MeEels on a rocky stream bed

  • Greenish, yellowish-brown or blackish body
  • Whitish belly
  • A continuous fin stretches around its rounded tail from its back to its belly
  • Males grow 2 feet long
  • Females grow 3 to 5 feet

Find Me

  • Fresh and brackish waters; streams, creeks, rivers, lakes, and ponds

I Like to Eat

  • Worms, small fish, mollusks, and crustaceans

Biologist's Note

  • Although many Americans think eels are slimy and gross, in Asia and Europe they are considered a delicacy. Most of the eels caught in the Bay region are exported overseas.

Cool Fact

  • During their migration back up the Bay’s rivers and streams, American eels overcome multiple obstacles to reach their destination. They can slide over rocks, dams, wet grass and other seemingly impassable blockages.

American Shad - Alosa sapidissima

Identify Meamerican shad

  • Thin, metallic body
  • Varies in color from greenish to dark blue
  • Deeply forked tail fin
  • Females are larger than males

Find Me

  • Coastal ocean waters, swaning in freshwater rivers and streams

I Like to Eat

  • Plankton, crustaceans, and small fish

Biologist's Note

  • Shad have a tree named after them: the shadbush blooms in spring, close to the time that shad return to the Bay's rivers to spawn.

Cool Fact

  • The largest American shad ever recorded was 2 feet, 6 inches long. The oldest American shad recorded in Maryland was 11 years old.

Atlantic Menhaden - Brevoortia tyrannus

Identify MeAtlantic Menhaden

  • Blue, bluish-green, or bluish-brown body
  • Length: 14 to 18 inches
  • Sides and find are silvery with a yellowish sheen
  • Deeply forked tail

Find Me

  • Throughout the Chesapeake Bay in large schools just below the water's surface

I Like to Eat

  • Filter feeder that eats plankton

Biologist's Note

  • The Bay is an important nursery area for juvenile menhaden because of its rich supply of plankton.

Cool Fact

  • Native Americans likely used menhaden to fertilize their corn fields. They called the fish “munnawhatteaug,” a word for fertilizer.
  • Although some people use it as bait, most menhaden caught in the Bay are processed for fish oil and livestock feed.

Atlantic Sturgeon - Acipenser oxyrhynchus

Identify MeAtlantic Sturgeon

  • Brown, tan, or bluish-black body
  • Whitish belly
  • No scales; 5 rows of bony plates called scutes
  • Length: up to 5 or 6 feet
  • Weight: males up to 90 pounds; females up to 160 pounds
  • Mouth is soft and toothless

Find Me

  • Bottom of freshwater rivers in the Chesapeake Bay region; spends most of its time in oceans

I Like to Eat

  • Bottom-feeder; mollusks, crustaceans, worms, and insects

Biologist's Note

  • Sturgeons are very sensitive to low oxygen, pollution and other poor water conditions. This, combined with their slow rate of maturity, damming of their spawning rivers and historic commercial fishing pressure, has caused the species to become very rare.

Cool Fact

  • Sturgeons are prehistoric fish that have existed for more than 120 million years. They were around during the Cretaceous period, when dinosaurs roamed the earth.
  • Sturgeons are the largest fish native to the Chesapeake Bay.

Black Drum - Pogonias cromis

Identify MeBlack Drum

  • Dark, silvery-gray body with a brassy sheen
  • Length: 40 to 60 inches
  • Weight: 50 to 100 pounds
  • Grayish belly, black fins and a high, rounded back
  • Deep notch in dorsal fin
  • Juveniles have 4 to 5 black verticle bars on their sides

Find Me

  • Bottom-dwellers around oyster reefs, wrecks, and piles in the Bay's deep channels

I Like to Eat

  • Bottom-feeder; mollusks and crustaceans

Biologist's Note

  • All drums are able to make a loud drumming or croaking sound by vibrating their swim bladder using special muscles.

Cool Fact

  • The black drum is one of the largest fish in the Bay. Young black drums that weigh less than 8 pounds are also known as puppy drums.
  • Part of the black drum's scientific name, Pogonias, means “bearded.” This refers to the fish’s chin barbels, which look like a beard. Cromis means “to croak.”

Brook Trout - Salvelinus fontinalis

Identify MeBrook Trout

  • Length: up to 12 inches, but most are no more than 10 inches
  • Body is wide in the middle and tapers at the ends
  • Dark, olive green back
  • Sides are bluish with yellow and red spots
  • Pale, yellowish-orange belly
  • Lower fins are orange-red and a white front edge

Find Me

  • Clear, cold, shaded freshwater streams, rivers, and lakes
  • Cool, clean waters
  • Not tolerant of waters above 75ºF

I Like to Eat

  • Insects, tadpoles, salamanders, small crayfish and small water snakes

Biologist's Note

  • Since brook trout only survive in the cleanest and coldest of waters, they are often considered a good indicator of the health of the waterways where they live.

Cool Fact

  • While all other trout in the Chesapeake Bay watershed have dark spots on a light background, the brook trout has light spots on a dark background. This coloring helps camouflage brook trout from predators.

Bull Shark - Carcharhinus leucas

Identify MeBull Shark

  • Length: range from 7 to 11.5 feet
  • Weight: 200 and 500 pounds
  • Females grow larger than males
  • Top side ranges from pale to dark gray
  • Underside fades to white
  • Short, blunt snout

Find Me

  • Coastal waters of tropical and subtropical seas between 100 and 165 feet deep
  • Both fresh and saltwater: estuaries, bays, harbors, rivers, and lakes

I Like to Eat

  • Fish, sharks, rays, turtles, dolphins, and sea birds

Biologist's Note

  • Bull sharks are named for their blunt snout, aggressive nature and tendency to head-butt their prey before attacking.

Cool Fact

  • Because bull sharks favor shallow coastal waters, they are among the most likely sharks to attack humans.

Cownose Ray - Rhinoptera bonasus

Identify Mecownose ray swimming

  • Brown to olive top
  • Cream bottom
  • Long and pointed wings
  • 3-foot wingspan
  • Long tail
  • Weighs around 50 pounds

Find Me

  • Coastal waters

I Like to Eat

  • Bottom-dwelling shellfish, such as soft-shelled clams and oysters

Biologist's Note

  • Cownose rays can wreak havoc on inderwater grass beds by rooting up plants in search of clams and oysters.

Cool Fact

  • This ray's name is derived from a notch in its head that looks like a cow's muzzle.

Mummichog - Fundulus heteroclitus

Identify MeMummichog

  • Stout-bodied with a flattened head
  • Rounded or squared-off tailfin
  • Pointed teeth and lower lip that juts out
  • Length: 5 to 6 inches
  • Coloration varies with sex and surroundings
  • Females have a brownish green body with 12 to 15 dusky vertical striped
  • Males are darker with a green or olive body with 15 silver vertical stripes

Find Me

  • Muddy, marsh waters, tidal creeks, and grass flats

I Like to Eat

  • Algae, plants, insects, small crustaceans, and mollusks

Biologist's Note

  • A tolerant species, the mummichog is able to withstand changes in temperature and salinity, low oxygen and pollution.

Cool Fact

  • "Mummichog" is a Native American word meaning "going in crowds"; mummichogs often form schools of hundreds of individuals.

Northern Puffer - Sphoeroides maculatus

Identify MeNorthern Puffer

  • Length: 8 to 10 inches
  • Yellow, browm or olive colored body with small prickles
  • Yellow or white body and a tiny, beak-like mouth
  • Dark, vertical bars on its sides and small, black spots on its back, sides, and cheeks

Find Me

  • Bottom-dweller in the Bay's flats and channel margins

I Like to Eat

  • Small mollusks, crustaceans, and other invertebrates

Biologist's Note

  • Puffers puff up by inhaling air or water into a special chamber near the stomach. If caught and thrown back into the water while inflated, a northern puffer will float upside down at the surface for a few moments, then quickly deflate and swim away.

Cool Fact

  • Although some types of puffers are poisonous, the northern puffer is not. In fact, it is a delicious fish, sold in fish markets as "sea squab."

Pumpkinseed - Lepomis gibbosus

Identify MePumpkinseed

  • Length: 4 to 6 inches, but up to 12 inches
  • Saucer-shaped body is mottled blue, orange, yellow, and olive green
  • Orange belly and black ear flaps
  • Forked tail fin

Find Me

  • Shallow, protected freshwater tributaries: lakes, ponds, reservoirs, streams, and creeks
  • Quiet, slow-moving waters

I Like to Eat

  • Snails, worms, insects, mollusks, small fish, and vegetation

Biologist's Note

  • The pumpkinseed can be confused with the bluegill, another sunfish. Pumpkinseeds can be distinguished by the wavy stripes on their cheeks and the bright red or orange border on their earflaps. However, bluegills and pumpkinseeds often interbreed, resulting in some confusing hybrids.

Cool Fact

  • They are a favorite of young anglers because they are playful and very easy to catch. Pumpkinseeds will eagerly bite onto nearly any small natural or artificial bait.

Red Drum - Sciaenops ocellatus

Identify MeRed Drum

  • Length: usually 20 to 30 inches, but can grow up to 5 feet and 90 pounds
  • Silvery body with a reddish or copper tinge
  • Silvery-gray to white belly
  • Squared tail fin
  • One or more large spots at the base of its tail

Find Me

  • Adults found near the shoreline
  • Juveniles are common in the Bay's shallows

I Like to Eat

  • Smaller fish, crabs, shrimp

Biologist's Note

  • Some scientists believe the purpose of the spot(s) near the tail is to mimic an eye. This fools predators into attacking the wrong end of the fish and gives the red drum a chance to escape.

Cool Fact

  • In 1984, a Virginia man caught the 59-inch, 94.2-pound world record red drum off the coast of North Carolina.

Striped Bass - Morone saxatilis

Identify MeStriped Bass

  • Length: 2 to 3 feet
  • Weight: 10 to 30 pounds
  • Varies in color from light or olive green to blue, brown, or black
  • Sides have 7 or 8 dark lines
  • White belly
  • Dark, forked tail
  • Deep notch in their dorsal fin

Find Me

  • Various habitats in the Bay; moving upstream to spawn in freshwater

I Like to Eat

  • Variety of small fish and invertebrates

Biologist's Note

  • The Bay is the largest striped bass nursery area on the Atlantic coast. Seventy to 90 percent of the Atlantic striped bass population uses the Bay to spawn.

Cool Fact

  • The striped bass is Maryland's state fish, and one of the most popular commercial and recreational catches in the Chesapeake Bay.

White Perch - Morone americana

Identify MeWhite Perch

  • Length: 7 to 10 inches
  • Weight: Rarely more than 1 pound
  • Silvery, greenish-gray body with faint lines on teh sides
  • Whitish belly
  • Highly domed, gray or blackish back
  • Mildly forked tail

Find Me

  • Flats and cannels in shallow, fresh and brackish waters
  • Quiet, freshwater streams

I Like to Eat

  • Small fish, insects, dead matter, and fish eggs and larve

Biologist's Note

  • It is believed that each Chesapeake Bay river has its own white perch population, since this fish likely does not venture far from the stream where it was born.

Cool Fact

  • White perch is a close relative of striped bass.

Last updated: April 23, 2018

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