Species
Stellwagen
Bank's Birds of Summer
The
same qualities that make Stellwagen Bank National Marine Sanctuary
an ideal site for spotting whales make it an excellent bird-watching
area as well. Over 40 species of seabirds regularly come to these
waters to feed on the abundant fish, plankton, and other marine
invertebrates. Among the more commonly seen birds during the summer
months are the following species:
Birds
sizes are based on measurements from bill tip to tail tip.
Gulls
These animals are opportunistic feeders, meaning that they will
eat whatever is easiest to get. When fish and shellfish are plentiful
and nothing else is around, that is what they will target. But
they will also eat garbage and eggs and chicks of other species.
Gulls proliferated when humans began piling wastes in dumps, providing
a veritable feast. They also learned to follow fishing boats to
gorge themselves on fish wastes. When the dumps closed and fishing
effort diminished, the gulls moved in on other nesting birds.
All gulls have many confusing juvenile phases and don't reach
their adult plumage until they are four years old. Here are some
descriptions of the more commonly seen adult gulls in the Sanctuary.
Herring
Gull
This is the gull that is most often referred to as the seagull.
It is the most common gull in Massachusetts throughout the year.
It has a pale gray back, black wingtips with white spots, pink
legs and feet, and a red spot on its yellow bill. These 23-26"
birds are year-round residents in Massachusetts Bay.
Greater
Black-backed Gull
Once seldom found, the black-backed gull has now become a common
sight in the Sanctuary throughout the year. It is one of the largest
(28-31") and most distinctive gulls with a large yellow bill
and black back and wings which contrast sharply with its snow-white
head and undersides.
Laughing
Gull
This gull is occasionally seen and heard in the Sanctuary (it
has a call that resembles raucous laughter). A bit smaller than
the herring gull (16-17"), it has a black head and red bill.
It can be distinguished from other gulls by its dark gray back
and wings which blend into black wingtips. They are usually found
in more southern waters.
Terns
Terns
are agile seabirds, smaller than gulls, with pointed wings, sharp
bills, and deeply forked tails. They catch small fish by hovering,
beak pointed down, then plunging into the water. There are many
species of terns but only two are regularly seen in the Sanctuary,
often on their way to and from shore on their fishing trips for
sand lance.
Common
Tern
This bird, which breeds along the Massachusetts coast, has a black
cap and bright red-orange bill with a dark tip. It has a light
gray mantle across its back and wings. These 13-16" birds
winter in Florida, the Gulf of Mexico and other more southern
locations.
Roseate
Tern
Listed as endangered, the Roseate Tern resembles the common tern
but has a dark (almost black) bill, longer tail points, and has
a paler color above. It averages 14-17". They can also be
identified by their distinctive raspy calls that sound like ripping
cloth. It winters from the West Indies to Brazil.
Arctic
Tern
On occasion, one may see one of these flying over the Sanctuary.
This tern has a bright blood-red bill all the way to the tip.
It has white cheeks but grayer breast and wings than the Common
Tern; also the Arctic Tern has a shorter bill and legs (usually
seen in more northern waters). The 14-17" bird winters in
the southern hemisphere.
Least
Tern
This tern is much smaller than the others (about 9"), with
a yellow bill and feet and a white forehead. It has much quicker
wingbeats (usually seen in more southern waters). It winters off
Brazil.
Gannets
Gannets
can be seen throughout the year in the Sanctuary, although they
are most common in the spring and fall when they are migrating
to and from their Canadian breeding grounds. These birds catch
fish by hovering up to 40 feet above the ocean, then plummeting
head first into the water. They are related to the tropical boobies.
Northern
Gannet
These are large (38"), white seabirds with extensive black
wingtips, yellowish heads, large bills and pointed tails. Juveniles,
which migrate north ahead of the adults, are variously mottled
with brown and white.
Storm
Petrels
These
small seabirds flutter erratically over the top of the waves or
paddle the surface with their feet while feeding on zooplankton.
Local residents referred to these birds as "Jesus bird"
because they look as if they can walk on water. The storm petrels
are considered to be one of the more abundant birds in the world's
oceans.
Wilson's
Storm Petrel
This long-distance migrator (breeds in Antarctic and ranges to
temperate and subarctic areas of northern hemisphere) is a small
(7"), sooty-brown bird, with paler wings and a conspicuous
white patch on its rump. Its tail is even at the end (no fork).
May be seen following ships.
Leach's
Storm Petrel
Unlike the Wilson's, this bird is not a long-distance migrator
but stays in the northern hemisphere. However, its appearance
is very similar to the Wilson's except that it has a forked tail.
It is a bit more brown, has a duller rump patch, and has longer,
more angled wings. The 8" bird does not follow ships.
Shearwaters
Shearwaters
are narrow-winged, gull-like birds that glide low over the water
in search of small fish, squid, crustaceans, as well as garbage
from ships. Although they can be very noisy at their nesting sites,
they are usually silent at sea. Greater and Sooty Shearwaters
are the most commonly seen species of shearwaters in the Sanctuary.
Greater
Shearwater
These 19" birds are dark above and white below, with black
caps and white collars on the backs of their necks. It also has
a white rump patch and a dark smudge on its belly. (Pictured Right)
Sooty
Shearwater
This bird is charcoal gray all over with grayish-white wing linings.
It is slightly smaller (17") than the Greater Shearwater.
(Pictured Left)
Manx
Shearwater
Only occasionally seen in the Sanctuary, the Manx is the smallest
(13") of the shearwaters found here. It is about half the
weight of the Greater Shearwater and does not have any white at
the base of its tail.
Phalaropes
Phalaropes
are small seabirds that spend most of their time at sea, but breed
in the Arctic and sub-arctic tundra during the summer. Large flocks
often migrate through the Sanctuary during the spring and early
fall. Their heavy plumage (and large amounts of trapped air) allow
them to ride high in the water, like corks bobbing at sea. When
seen, they may be sitting on the water, spinning in place, then
stabbing the water with needle-like beaks for copepods and other
zooplankton. Unlike most other seabirds, the females are larger
and have a more brightly colored summer plumage than the males.
They look a like sandpipers with lobed toes.
Red
Phalarope
These 8-9" birds have white faces, darker area at top of
head and deep brick-red underparts that extend from the neck to
the tail. Its upperparts are mainly blackish with some brownish
edging. The adult, breeding female's needle-like bill is yellow
with a black tip. Others have darker bills.
Northern
or Red-necked Phalarope
These birds are slightly smaller (7-8") than their red cousins,
with more blackish-slate coloration on their heads, a white chin
and a red patch on their necks. This is the most common of the
two "sea snipes." Their underparts are mostly white
and their upper parks are blackish with brownish edging.
Jaegers
These
are the hoodlums of the sea world, also known as "robber
gulls." Jaegers are falcon-like birds that pursue gulls and
terns, forcing their hapless victims into dropping or disgorging
their food. The jaegers have dark and light phases, with subadults
exhibiting a confusing array of plumages.
Parasitic
Jaeger
This 18" bird's elongated central tail feathers stick out
1-3", ending in sharp points. The bird has a slightly hooked
beak and shows a white wing flash (bits of white on its wings).
Pomarine
Jaeger
Larger (22") and heavier than the Parasitic Jaeger, the Pomarine's
tail feathers are also broader and twisted, not pointed. It also
has a slightly hooked beak, and in its light phase, heavier barring
below (bands of dark on the underside).
Cormorants
Cormorants
have slender beaks with hooked tips, long necks, elongated bodies
and are often seen in a distinctive "spread-eagle" pose
as they sit on moorings, pilings, and shore-side power lines.
These birds are underwater-pursuit swimmers of fish and crustaceans.
Double-crested
Cormorant
Among the most commonly seen shore-based birds when leaving port
to head out to the Sanctuary are these cormorants. Black with
a metallic-sheen (greenish-gloss), yellow bill and green eyes,
cormorants are among the larger birds (33") in the Sanctuary.
Alcids -
Birds of Winter
The waters over Stellwagen Bank can appear desolate during the
winter. The humpback, finback, and right whales have migrated
south, and the swallow-like storm-petrels no longer can be seen
bouncing along the surface of the water. But awards still await
the hardy nature lover willing to brave the wind and waves.
The return of the cold marks the arrival of the alcids-a group
of stocky black-and-white seabirds that include one of the most
recognizable of all birds, the rainbow-billed puffin.
Alcids are the northern hemisphere's equivalent of penguins, although
the two groups are not related. In fact, a now extinct alcid,
the flightless Great Auk, Pinguinus impennis, was called a penguin
long before the southern hemisphere penguins were described. Like
the penguins of the Antarctic, alcids walk upright -- their legs
set towards the backs of their bodies. And like penguins, alcids
thrive in the cold water. They nest in dense colonies along the
rocky coasts and islands in the high latitudes of the North Atlantic,
North Pacific, and the Arctic Ocean. On shore, alcids waddle clumsily,
and in flight, they resemble giant, stubby-winged insects, but
in the water, where they spend most of their lives, they are agile
swimmers and prodigious divers. Using their wings as flippers,
alcids swiftly pursue crustaceans and small fish, such as herring,
at great depths, often emerging with their bills filled with multiple
prey to bring back to their nests. One species, the Common Murre,
has been recorded diving to depths of 550 feet.
During the summer, spectacular colonies, often containing thousands
of birds, cram themselves along ledges, inside crevices, and between
boulders. In sites supporting multiple seabirds, the species segregate
themselves. For example, on an island off the coast of Newfoundland,
Black Guillemots nest at the base of the cliffs, Common Murres
on ledges along the cliffs, Razorbills in crannies along the cliff
face, and Atlantic Puffins in the grassy slopes on the tops of
the cliffs. Most species are monogamous and produce one brood
per year of one to two chicks. In some species, pairs may remain
together for several years. Chick mortality is as high as 90%
during the first year. Gulls prey on chicks, and others succumb
to the harsh conditions at sea. But birds that survive the first
few months of life often live into their twenties.
Their habit of nesting in dense colonies and their awkwardness
on land made alcids easy targets for hunters seeking eggs, meat,
and feathers. In the early 19th century, this overexploitation
led to the extinction of the Great Auk -- a two-and-half-foot
tall flightless alcid that formerly nested from Newfoundland to
Britain. By the 1840s, colonies of other alcid species had also
disappeared from most islands in the Gulf of Maine.
Currently, some alcids are recolonizing their former nesting sites.
Starting in 1973, Stephen Kress of the National Audubon Society
and current director of the Maine Coastal Sanctuary program pioneered
efforts to restore seabirds to their historical nesting sites
off the coast of Maine. Kress and other scientists and volunteers
of the Audubon Society's Puffin Project transported Atlantic Puffin
chicks from Newfoundland to Eastern Egg Rock in Muscongus Bay,
placed decoys and ceramic eggs around potential nesting areas,
and played audio tapes of nesting puffins and chicks. In 1981,
for the first time in 150 years, puffins returned to the island
to nest. Today, over 15 puffin pairs are nesting on Eastern Egg
Rock. Conservationists have also lured puffins to two islands
near the mouth of Penobscot Bay. Twenty-five pairs are nesting
on Seal Island, and over 150 pairs, along with 60 to 80 pairs
of Razorbills, are nesting on Matinicus Rock. Puffin Project workers
are currently deploying decoys and audio tapes to lure Razorbills
to Seal Island and Common Murres to Matinicus Rock. They have
also used these methods to reestablish colonies of other seabirds,
including Common, Arctic, and endangered Roseate terns.
Kick-starting
these colonies is a real challenge, according to Steve Edwards,
an Audubon Society naturalist aboard a puffin-watch cruise that
visit the new colonies. Edwards estimates that of the 3,000 islands
off the coast of Maine, 30 are suitable for recolonization. The
islands must contain enough suitable habitat to support many nests,
because alcids "like being a face in the crowd." Islands
must also be free of humans and introduced mammals such as rats
or foxes that consume chicks and eggs and be far enough off the
mainland that owls and other predators can't make the journey
over to prey on the colonies.
Even after the colonies are established, the sites need constant
maintenance, according to Stephen Kress. Gulls, having benefited
from the proliferation of garbage dumps and fishing boat waste,
have replaced humans as the pilferers of nesting alcids. Not only
do gulls compete with alcids for nesting sites, they eat both
young and adult birds. Therefore, gull populations on these islands
must be constantly monitored and controlled.
Alcids are now protected in the Gulf of Maine. But hunting is
not the only activity that threatens alcid populations. Kress
says that in the waters off of Newfoundland and northern Europe,
the commercial fisheries compete with alcids for bait fish such
as sand lance and herring, and that overharvesting of these fish
may be contributing to regional declines of alcids. Scores of
diving birds become entangled in drift nets and drown. But oil
spills are the conservationist's greatest nightmare. An oil spill
in the wrong place could wipe out entire colonies, putting a severe
dent in the world population. For example, 90% of all Common Murres
nest in only three colonies in Canada. By increasing the number
of nesting colonies, conservationists hope to lessen the impact
of localized disasters such as oil spills.
As summer ends, alcids leave their nests and scatter southward
seeking productive, ice-free waters where they can dine on the
bounteous fish and marine invertebrates. Stellwagen Bank is one
such site. The number of alcids off the Massachusetts coast likely
varies depending on the distribution of food and the severity
of the winter. A deep freeze up north forces many birds south,
and storms, particularly in late fall and early winter, may push
alcids towards shore. But because few people venture out over
the Bank during the winter to survey the birds, data on the numbers
of alcids that frequent the sanctuary are scarce. During years
when the weather cooperates, birders survey the sanctuary during
the annual Stellwagen Bank Christmas Bird Count in mid-December.
However, most sightings come from land. Good locations for spotting
alcids from land include Andrews and Halibut Point in Rockport,
Race Point in Provincetown, and Nauset Lighthouse in Eastham.
First Encounter Beach in Eastham can also be a great place to
observe alcids following severe northeast storms in November.
Those who do go out seeking alcids must not only be impervious
to the cold, but they must have sharp eyes. Alcids are difficult
to spot as they bob among the waves, only to dive and stay under
water before the boat can approach close enough to get a decent
view. The fact that alcids spotted during the winter are often
immatures or in their winter plumage makes distinguishing the
species especially challenging.
Six species of alcids breed in the North Atlantic and migrate
to the waters off the coast of Massachusetts in the winter. The
following are descriptions of what to look for. Wayne Petersen,
field ornithologist for the Massachusetts Audubon Society, provided
the information.
Razorbills
Alcid-seekers plying the waters over Stellwagen Bank or
staring out from the headlands on Cape Cod or Cape Ann are
more likely to see Razorbills than any other alcid, especially
from November through January. Razorbills are black on top
and white below with a pointed tails that are often cocked
upwards. But their most distinguishing feature is their
large, laterally-flattened bill. A vertical white band running
through the middle of the bill is also characteristic of
adults. The bills of immature Razorbills are easy to confuse
with those of murres. Juvenile bills are shaped the same
as adult bills, but are smaller and lack the white band.
In flight, Razorbills have a hunchbacked, bull-necked appearance.
Other helpful fieldmarks for flying Razorbills include a
white trailing edge on the wing and white on either side
of the black tail.
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Murres
Two species, the Thick-billed Murre and the Common Murre,
nest in the North Atlantic Ocean. During most winters, bird
watchers usually report seeing a handful of Thick-billed
Murres along the Massachusetts coast, most often in late
winter. But during some seasons, the numbers increase dramatically,
especially during cold winters when extensive icing closes
large areas of their winter range. Following a major storm
in December, 1976, birders reported seeing a record number
of 3,000-5,000 Thick-billed Murres flying past the Massachusetts
coast.
Common Murres rarely venture close to shore, but they may
occur regularly over Stellwagen Bank. However, following
oil spills off of Cape Cod and Nantucket, oiled murres regularly
get swept ashore, indicating that they do winter at sea
off of Massachusetts. The two species are difficult to distinguish
from each other. In winter, both birds are black on top
and white below with white throats and cheeks. However,
the dark hood of the Thick-billed Murre extends below its
eyes, whereas the Common Murre has a dark stripe running
from its eyes to its cheeks. The Common Murre also has a
sharper, slenderer bill and is browner on the back than
the Thick-billed Murre. In flight, murres appear more streamlined
than the thick-necked Razorbills.
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Dovekies
Dovekies are chubby, starling-sized alcids that feed on
planktonic crustaceans. They are believed to be especially
concentrated at the upwelling zones along the edge of Georges
Bank where food is particularly abundant. During the fall,
storms often deflect Dovekies towards land, but Dovekies
are seldom seen from shore in Massachusetts after December.
Like all alcids, Dovekies are black above and white below.
However, their small size, short necks, and stubby beaks
make them easy to distinguish from other species, both in
the water and in flight.
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Atlantic Puffins
Atlantic Puffins are undoubtedly regular visitors to Stellwagen
Bank and waters off the Massachusetts coast from October
to mid-winter. They are chunky, black and white birds with
white cheeks and enormous triangular, tricolor bills, inspiring
the nickname "parrots of the sea." Puffins are
smaller than Razorbills and Murres but not as tiny as Dovekies.
In winter, Atlantic Puffins shed the colorful bill plates,
so their bills are smaller and less gaudy, but still the
same triangular shape. Their white cheeks also turn gray.
In flight, puffins can be identified by their rounded, solid
black wings, bright orange feet, and big-headed appearance.
Juveniles have much smaller, gray, unpuffin-like bills.
However, juvenile puffins can still be identified by their
gray cheeks and chunky shape. Some ornithologists speculate
that juveniles, after fledging, actually drift south to
the Massachusetts coast, following the Labrador current
instead of flying.
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Black Guillemots
Black Guillemots are slender, duck-like alcids with fairly
long pointed bills. More than any other North Atlantic alcid,
Black Guillemots stay close to rocky shores. During the
winter, they can often be seen off of Provincetown, Cape
Ann, and Boston's outer harbor islands, but they usually
do not venture as far offshore as Stellwagen Bank. In winter,
Black Guillemots are white molted with black, and have large
white patches on top of the wings. They also have orange
legs and feet.
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Other
Birds
Gulls
There is never a shortage of gulls over Stellwagen Bank, and winter
is no exception. Because most gulls take three to four years to
reach their adult plumages, and because they have several distinct
immature plumages, identifying species can be tricky. The following
descriptions are of adult winter plumages, although immatures,
particularly first year birds, are also common during the winter.
Black-legged Kittiwakes
Black-legged Kittiwakes, which feed on small fish such as
sand lance, are abundant over Stellwagen Bank during the winter.
They are small (half the size of a Herring Gull), have black legs,
an unmarked yellow bill, and pure black wingtips that look as
if they had dipped their wings in ink. In winter, Black-legged
Kittiwakes have a dusky spot behind each eye. The much larger
Herring Gull has a gray mantle (back), pink legs, a yellow bill
with a red spot, and black wingtips with white spots. In winter,
herring gulls have heavy brown streaks on their heads and necks.
The large and distinctive Great Black-backed Gull has a heavy
yellow bill with an orange spot on it and a black back and wings
that contrast sharply with its snow-white head and undersides.
Glaucous Gulls and Iceland Gulls often attend fishing boats during
the winter. They are gray above with white underparts, pink legs,
and yellow bills with orange spots like the Herring and Great
Black-backed gulls. Both species lack black wingtips. The less
common Glaucous Gull is larger and has a heavier head and bill
than the Iceland Gull.
Northern Gannets
Northern Gannets are large, white seabirds with black wingtips,
a yellowish wash on their heads, large bills, and pointed tails.
Juveniles are variously molted with brown and white. Gannets catch
fish by hovering up to 40 feet above the ocean, then plummeting
head first into the water.
Other Northern Fulmars and Great Skuas winter well offshore,
but occasionally can be seen in the Sanctuary, particularly after
storms.
(Information provided by Wayne Petersen, field ornithologist for
the Massachusetts Audubon Society)
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