to Common Life of Narragansett Bay
and Rhode Island Coastal Waters
Save The Bay
100 Save The Bay Drive
Providence, RI 02905
SAVE THE BAY’S UNCOMMON GUIDE
SAVE THE BAY’S UNCOMMON GUIDE
to Common Life of
Narragansett Bay and
Rhode Island Coastal Waters
SAVEBAY.ORG
2nd Edition
OCEAN
ESTUARY
SHORELINE
Fish
WHERE DO I FIND IT?
Use these icons as a quick
reference to where you
might find a particular
Bay species. Icons denote
a species’ predominant
habitat; other preferred
habitats are mentioned
within the text.
Narragansett Bay is home to more than 100 species of fish from oceanic sharks
and tuna to river herring and brook trout. Some are resident species, living in the
Bay year-round, while others are migratory, visiting only seasonally or accidentally.
The Bay is famous for striped bass and bluefish, which are abundant from spring
through fall.
Most fish belong to either the class Chondrichthyes (cartilaginous fish, also called
elasmobranchs) or the class Osteichthyes (bony fish). Fish make up half of the
more than 40,000 species of vertebrates in the world: 90% of those are bony fish
and 10% are elasmobranchs.
Fish are cold-blooded vertebrates that breathe with blood-rich structures called
gills, which extract dissolved oxygen from the water. Most fish have scales and a
slimy, mucus coating that protects them from disease. Many species of fish have a
swim bladder, which is a gas-filled sac that inflates or deflates to maintain neutral
buoyancy in the water. Gas is taken in and expelled through the mouth and gills.
Sharks, skates, clingfish and flatfish do not have swim bladders.
ANATOMY OF A FISH:
Spiny dorsal fin
Caudal (tail) fin
Soft dorsal fin
Gill cover
Nostrils
Lateral line
Eye
Peduncle
Mouth
Vent
Pectoral fins
Scales
Pelvic fins
Anal fin
Most bony fish lay eggs and mate through external fertilization. The female
produces thousands, sometimes millions, of eggs, which are dispersed into the
water and fertilized. Most fish eggs float, but there are exceptions such as those of
the winter flounder. Eggs and larvae are planktonic (free floating) until large
enough to sink. Most elasmobranchs reproduce through internal fertilization and
lay few eggs or egg cases, with some species birthing large, live individuals.
This section of the Uncommon Guide categorizes Narragansett Bay fish into
groups determined by body shape and/or habitat preference. Sharks and skates
are cartilaginous. The bottom and rock dwellers include species that may resemble
rocks, such as the oyster toadfish, or fish like the cunner that can camouflage with
the mud. Flatfish have adapted to live on the bottom with both eyes on one side
of the body. Minnows are found in the shallow tidal ponds around the Bay, have
small bodies and are often used as bait. Fish that are found in the open water, such
as the torpedo-shaped tuna, can undergo extreme migrations at very fast speeds.
Anadromous fish live in salt water but migrate to spawn in fresh water. Finally,
there are those with unique shapes, such as the seahorse and various tropical fish
that are accidentally transported into the Bay.
149
Fish
Blue Shark
Sharks and Skates
sandpaper when rubbed against the grain. Five or more
gill openings can be seen on the side of the head.
FIELD MARKINGS:
Bright indigo blue
back, fading to light
blue-gray on the sides
with a white underside. Size: averages
7 to 8 feet long; can
grow up to 12 feet.
The snout of the blue shark is long with a well-rounded
tip. It has large, pointed and serrated teeth that are well
developed and packed close together in its mouth. The
blue shark feeds on smaller fish such as herring, spiny
dogfish and mackerel. It is also a scavenger, feeding on
the carcasses of fish, whales and other sharks.
This shark is often seen swimming lazily at the surface,
basking in the sun, and is not believed to swim to great
depths. However, it is capable of attaining great speeds.
The blue shark is highly migratory and found in all of the
world’s oceans.
Relationship to People
Distinguishing Features and Behaviors
Sharks, skates and rays belong to a particular group of
fish called elasmobranchs, meaning their entire skeleton
is made of cartilage rather than bone.
The blue shark is distinguishable from other sharks
because it has a slender body and long, narrow pectoral
fins. Its body is thickest at the midsection and tapers
toward the head and tail. This shark has two dorsal fins
— the second is about half the size of the first — and an
asymmetrical tail.
COLLOQUIAL NICKNAMES:
Blue Dog
SCIENTIFIC NAME:
Prionace glauca
This animal gets its name from the distinctive blue
coloring that fades to white on its underside. When
the shark dies, the blue coloring turns gray. The tough
skin is composed of hard scales that are abrasive like
150
The blue shark is the most abundant of oceanic sharks.
Its presence in Narragansett Bay waters is rare, but it
has been spotted near the mouth of the Bay while
migrating up and down the Atlantic coastline. This
species is considered dangerous to people, but encounters
are extremely unusual, and no attacks have ever been
documented in Rhode Island waters.
HABITAT:
Open ocean,
occasionally near
mouth of the Bay.
Like most pelagic shark species, the blue shark population
is severely threatened by overfishing. Recent research on
the potential use of cartilage to heal cancer has lead to
an increase in the harvesting of these slow-growing fish.
SEASONAL APPEARANCE:
Summer.
The practice of “finning” has decimated the population of
many species of oceanic sharks, including the blue shark.
Finning is the cruel practice of removing the fins from the
shark and releasing it alive. Shark fin soup is considered a
delicacy in many Asian countries that receive shark fins
from fishermen all over the world.
SENSITIVITY LEVEL:
151
Northern sea robin, pg. 166
Long-finned squid, pg.114
Narragansett Baykeeper John Torgan (right)
with his father Philip exhibit their catch of
the day, a bluefish (pg. 190).
Harp seal, pg.292
Harbor seal, pg. 290
LEFT TO RIGHT: Bayberry (pg. 42)
and beach plum (pg. 43) are just
two of the 20 native droughtand salt spray-tolerant plant
species present in the Save The
Bay Center coastal buffer.
Mallard, pg. 244
Fish
Little Skate
Sharks and Skates
Unlike bony fish, skates lack the mechanism to pump
oxygenated water over their gills. Because skates spend
most of their lives on the bottom, they breathe through
specialized organs called spiracles, which are slitlike
openings near their eyes. Water is taken in through the
spiracles, passes over the gills and then leaves the body
through five pairs of gill slits underneath.
FIELD MARKINGS:
Light brown to gray
on the back, paler
toward the edges of
the pectoral fins;
white or gray belly.
Size: averages 16 to
20 inches long, 8 to
16 inches wide.
The skate has many rows of blunt teeth, resembling sandpaper, that help grind food between two well-developed
jaw plates. Skates feed on a diverse diet of shellfish, crabs,
sea squirts, worms, amphipods, squid and small fish.
Male skates are distinguished by two long claspers along
their pelvic fins, which they use to hold onto the female
and transmit sperm. Little skates copulate many times in
a year. The female lays two large eggs that develop inside
capsules, or egg cases, which are often found attached
to seaweed. The empty black capsules wash ashore after
the young skates have hatched. Resembling square coin
purses with prongs at each corner, the capsules are
commonly called “mermaids’ purses.”
Egg Case
COLLOQUIAL NICKNAMES:
Common Skate,
Skate, Raja
Distinguishing Features and Behaviors
Like rays and sharks, skates belong to a group called
elasmobranchs, which includes all fish with a skeleton
made entirely of cartilage. One of the more common
species of skate found in Narragansett Bay is the little
skate. Its body is shaped like a flattened, rounded triangle
and is well-adapted for life on the bottom of the Bay.
The skate is armored along its back and tail with sharp
spines that are used defensively, but it is not a sting ray.
Females have more spines than males.
SCIENTIFIC NAME:
Raja erinacea
HABITAT:
Shallow water, sandy
and muddy bottoms.
Relationship to People
The little skate is quite common in Narragansett Bay.
It has been increasing in numbers since 1970 and is
now one of the dominant creatures in bottom-fish
communities. They are frequently strung together and
used to bait lobster pots. Because they reproduce slowly,
their populations could decline if overexploited.
SEASONAL APPEARANCE:
Spring, summer, fall.
Historically, skate have not been a commercially important
species, but it is becoming more popular as a food fish,
frequently marketed by its Latin name, Raja. Skate wings
are sometimes cut into small, round pieces and falsely
marketed as scallops.
SENSITIVITY LEVEL:
152
153
Fish
Sharks and Skates
Mako Shark
Makos range the world’s tropical and temperate oceans,
but appear off the Rhode Island coast in summer to
feed on the abundant foraging species’ schools.
FIELD MARKINGS:
Gray to cobalt blue.
Size: up to 12 feet.
Relationship to People
While mako sharks have been known to attack humans,
such attacks are extremely rare and none have been
documented in Rhode Island.
Makos are considered excellent table fare and are
targeted by recreational and commercial anglers. The
state record fish weighed 718 pounds.
Shortfin Mako
While the official status remains unknown, populations
of makos and other large coastal sharks have declined
significantly since the 1970s and are now the target of
federal regulations. Mako populations have suffered
worldwide as a result of fishing pressure and bycatch
in the tuna and swordfish fisheries.
HABITAT:
Open ocean along
the Gulf Stream,
generally in deep
water, but may range
in close to the mouth
of the Bay to chase
bluefish and other
bait species.
Distinguishing Features and Behavior
Sharks, skates and rays belong to a particular group
of fish called elasmobranchs, meaning their entire
skeleton is made of cartilage rather than bone.
The shortfin mako is an apex predator of the ocean
and is noted for its agility and speed (over 30 miles
per hour). When hooked, makos have been known to
make spectacular, cartwheeling leaps. They have
compact torpedolike bodies with a set of serrated
triangular teeth in rows.
COLLOQUIAL NICKNAMES:
Shortfin Mako,
Atlantic Mako
SCIENTIFIC NAME:
Isurus oxyrinchus
SEASONAL APPEARANCE:
Summer.
Makos are primarily piscivores, feeding on other
fish such as bluefish, herring, mackerel and small
tunas. They have also been known to eat some
invertebrates, like squid.
154
SENSITIVITY LEVEL:
155
LEFT TO RIGHT:
A spider crab (pg. 96),
blue mussels (pg. 104)
and a purple sea
urchin (pg.134)
cohabitate in a touch
tank at the Save
The Bay Exploration
Center.
Short-spined brittle star, pg.140
Save The Bay works
to restore the Bay’s
historic eelgrass beds
(pg. 2), home to
flounder, scallops
and crabs. Photo
by Tom Freeman.
A family of Canada geese (pg. 232) walk the Save The Bay Center grounds.
Floating moon jellies (pg. 56) on view at the Save The Bay Exploration Center.
Oyster toadfish, pg. 168
Asian shore crab, pg. 66