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BIRD
COLUMN FOR By
Benjamin P. Burtt A day or two after a hurricane strikes the Many of these are pelagic birds. These are birds
that have largely cut their ties with the land and spend their lives in the
open ocean. They return to land only to breed. Some are from the Atlantic
Ocean, east of South America and others from the Caribbean. Their pictures are shown in your field guide, but
we normally never see them unless we are in a boat far at sea. They include
shearwaters, fulmars, petrels, and storm petrels. A very rare one would be an
albatross , a booby, a frigate bird or a tropicbird. Other birds that show up here after a hurricane
include some that are normally found only on the edge of the sea from New
England south to Florida and along the Gulf coast west to Texas. Today, I want to discuss how the birds get here and
what sort of weather conditions they encounter along the way. We will explore
the dangers such storms cause for the birds and why so many are killed in a
hurricane. The
Nature of a Hurricane How did hurricane Isabel affect birds? When strong
winds were felt, many small land songbirds took shelter to wait it out. While hurricane Isabel approached from the south
east, it is important to know that hurricane winds are not steady winds from
one direction. The storm is circular and like a huge whirlpool, 700 miles
across, it draws the winds and the birds in them in a spiral path towards the
center in a counter-clockwise direction. When the storm is forming over the ocean to the
south and east, pelagic birds are swept into this region from all points of
the compass like swimmers going downstream in a strong current. While the storm is still over the ocean, the whirlpool
begins to form a small area in the center where the winds are gentle and the
sky may be clear. This is called the "eye" of the hurricane. In
Isabel, the eye was 50 miles in diameter, which is large as eyes go. Land birds may be migrating south at the time and
passing over the ocean heading for South America. They too may be drawn into
the storm and end up in the eye along with the pelagic birds. After a time, thunder storms form around
the eye and before long and it is ringed by a wall of thunder storms,
shoulder to shoulder about 7 miles thick. This is called the eye wall. The highest winds in the storm are just outside the
eye wall and were slightly over 100 mph in Isabel. The birds in the eye are in a sort of sanctuary for
there is almost no wind and it may even be sunny. The water below the thunder storms in the
eye wall becomes turbulent and there are 40 to 50 foot waves there. These
waves move right into the calm air of the eye, so while the air is quiet in
the eye, huge waves are commonplace. The pelagic birds can no longer rest on the surface
of the water or even find food there. They must keep flying. Land birds in
the eye must keep flying too. This eye moves along to the There are many birds flying about within the eye
and the hurricane hunter aircraft have reported great flocks there. Ships
that have been in the eye report many pelagic birds flying about and lots of
land birds resting on the ship and in the rigging. On early Thursday morning, September 18, high winds
began to buffet the If the land birds in the eye could see the ground,
some would fly down to rest. However, over the land, the eye fills up with
clouds and the visibility is poor, so that all birds must continue flying. If a pelagic bird became exhausted, it might be so
weak that it would drop down through
the clouds and could end up in someones back yard. Check the
Hurricane Maps At this point, I suggest that you look at two maps
that I have made. The first shows the path of the storm and the second, shows
how the strong winds are arranged around the center of the storm.
Now back to the hurricanes movement over the United
States. As the eye of the hurricane with its bird passengers, moved over the
land, the winds on the south side of the storm would sweep birds flying
there, out over the ocean. Those on the north side of the storm would be swept
to the west and would go inland sometimes as far as Ohio and Indiana. The hurricane moved to the northwest. As the storm
passed over central Virginia at 23 mph, the winds within it dropped to 65
mph, some birds that could see the ground probably left the storm there. Six hours after passing over central Virginia, the
storm was over the panhandle of West Virginia and the spiraling winds were
down to 50 mph. However, the storm had picked up speed and was moving over
the land at 35 mph. As the storm moved across West Virginia into
western Pennsylvania on September 19, the winds decreased still further. The
visibility was better and birds could leave the storm and return to the
earth. A Pelican
turned up at DeRuyter An immature brown pelican wandering about on the
east coast was in the air and apparently, flew northwest to avoid the storm.
The winds on the fringes of the hurricane were pushing it in that direction. When the center of the hurricane was near
Pittsburgh, the winds were now pushing the pelican north. With this tail wind
the bird eventually found itself over southeastern Onondaga County and
spotted the Deruyter Reservoir on Friday September 19. The pelican cruised over the Reservoir and down
below it could see some people struggling to secure their boats, their docks
and moorings in the wind and rough water. The pelican saw Berry Buyea and Charles Beeler Sr.
and Jr., Mike Curran, John Kennedy and
Jack Konig who shouted, "look there's a pelican" but everyone else
laughed. Later however, John
Kennedy took some pictures when the
bird was far out over the water.
As the pelican flew down the lake, it might have
thought to itself, "You fellows think you are having a tough time, you
should see what I've just come through." The bird stayed two days and then disappeared. The
only previous record in Central New York ( Region 5) was in 1920. While
John's photograph was taken at quite a distance, the bird could be
identified. It was the shape of a pelican and was dark in color with no white
patches, and that was all that was needed. Many pelagic birds turned up on Lakes Erie, Ontario
and Cayuga. These birds had been flying steadily without food or rest and
many died and the survivors that arrived were weak. A
White-Faced Ibis turned up at Montezuma About a week later, an immature white-faced ibis
turned up at Montezuma National Wildlife Refuge. Normally found on the Gulf
coast in Louisiana and Texas, it may have strayed to the east before the
storm and then was swept north to establish the first record of its species
in upstate NY. To see two nice photographs of that bird, go to Images and
select "White-faced Ibis". The second hurricane map shows the
normal range of this bird where it is colored in red.
Many
Birds Died in the Hurricane How many birds were killed in the storm? We will
never know, but now that we understand what the hurricane was like, lets
review what they went through. Birds trapped in the eye when the storm formed over
the ocean, could not escape through the eye wall because of the strong
incoming winds. If they were still alive when the storm moved over the land,
they eventually may have been able to fly down to the surface. This is
probably the way the surviving pelagic birds got here. Many probably died from exhaustion and fell to the
ground along the way for they had been flying for two days without rest. Land birds that were skirting the storm on the east
and northern side were not likely to be caught in the storm, but the
spiraling wind did push them far inland. However, birds that flew too close to the storm could
be swept into it by the winds that spiraled in. When they reached the eye
wall, they would probably be drawn into the wall itself. Instead of passing through the wall into the eye,
the strong winds in the eye wall carried them upward in a tight spiral. How
high the birds would go we do not know, but the spiraling winds go up 17,000
to 50,000 feet. The higher the birds were carried, the lower the temperature
and the birds could encounter hail and subfreezing temperatures as they were
carried upwards. It does not seem likely that they could survive.
Battered and exhausted, they probably were not able to keep on flying and
would die there in the sky. The carcasses would be scattered over a wide area
and never be noticed. The hurricane made for some interesting birding,
but the birds from the Atlantic Ocean or the coast that were seen, were the
survivors and probably many more perished along the way. There is one other way that the hurricane can make
some unusual birds be visible in Central New York. The phalaropes are
sandpiper-like birds, but they swim as well as wade. They breed in Canada and
some very far to the north. They migrate south to spend the winter at sea.
Since they travel overhead at high altitude, we seldom see them. At the time
of the hurricane, many turned up on Lake Ontario and Cayuga Lake. These birds
were not blown here by the storm, but as suggested by Dr. Kevin McGowan of
Cornell, they probably, saw the huge storm ahead of them and veered to the
west to avoid it and then came down on the lakes to rest and sit out the
storm. I am indebted to several people who helped me
become more knowledgeable about hurricanes. Chris Brandolino and Peter Hall
of WSTM-TV were the first people I contacted. They shared some of their
knowledge and told me about the National Hurricane Center and its web site
with all the records of Hurricane Isabel. There I was able to see images of the storm at six
hour intervals. I was also able to consult with a hurricane specialist, Tracy
Stewart who through a number of emails answered many questions for me. Thanks
to you all! Coming in the next column on November30: The results of the November Feeder Survey and the announcement concerning the start of the December survey. To get in touch with Benjamin P. BurttVia Mail: Write to B.Burtt, Stars Magazine, P.O. Box 4915, Syracuse,, NY 13221. Via E-mail: Send to
features@syracuse.com. Be
sure to put “For B.Burtt” in the subject line. |
