Georgia
to Cape Cod: Right Whales on the Move
Holy Cow!
Counting Right Whale Calves
Photo
East Coast Ecosystems
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Right now,
the great whales are taking care of their newest generations on calving
and birthing grounds in Earth's oceans. This week we'll share news about
the Northern Right whale. The right whale is the most endangered of the
great whales. Scientists believe there are only 300 or so of these animals
left in the North Atlantic. After the end of commercial whaling, people
thought the Northern right whale population was recovering. But evidence
since about 1990 shows a decline. Biologists estimate that a population
of 300 can hardly support the genetic diversity necessary for a healthy
and thriving population to continue, and many feel the species may be
functionally extinct.
But there
are new calves to count this spring! Read on for background information
about these whales' whereabouts, the status of their numbers (2002 figures),
news from the calving grounds, and some very real dangers. With the troubles
it faces, you will wonder why this whale is called the RIGHT whale. (We'll
tell you that answer at the end of today's report!)
Oh
Where Oh Where Can That Right Whale Be?
The migration
route of the right whale is not as cut-and-dried as other animal species.
Because of their marine habitat and the difficulty of placing and keeping
radio tags on these animals, it is difficult to monitor their migration
route. The map at the right can help you understand what we do
know. Can you find these areas?
- We know
that the pregnant females seek the warmer
waters of more southern latitudes to birth and raise young calves. Many
can be found in the warm coastal waters off of Georgia and northern
to central parts of the Florida coast.
- Some non-pregnant
females, males and juveniles have been seen feeding during the
winter months in Cape Cod Bay (and to a lesser extent southern Stellwagen
Bank).
- Feeding
continues during April through June in the Great South Channel, an area
between Nantucket and Georges Bank, which is also the major north-south
shipping channel off the NY-MA coast. But this is only a fraction of
the entire population. We do not know where most of the animals are
during this time period.
- In late
summer and early fall, right whales congregate in the Bay of Fundy and
off the coast of Nova Scotia in areas believed to be breeding and feeding
grounds. Scientists suspect there may be other calving, breeding and
feeding grounds, perhaps farther offshore, that we don't yet know about.
Population
Trends and Concerns
Right whales probably never had a large population to begin with, and
constant whale hunting over centuries kept the numbers down. By the mid
1930s, when the whales received international protection, their numbers
were pitifully low. Although hunting has stopped, other factors may be
keeping the population numbers down. Low birth rates and entanglement
in fishing gear are major causes of right whale deaths. Interactions with
humans and changes to the right whale habitats may be affecting the health
of individual animals and the birth rate. But collisions with ships are
the number one known cause of right whale mortality. The migration route
takes the animals across the paths of major shipping channels into many
ports along the eastern seaboard: Portland, Boston, Newport, New York,
Chesapeake Bay, Charleston, and Port Canaveral are some. During this time,
whales are in danger of being struck by large ships that are moving perpendicular
to them. When whales and ships meet, it's usually the whales that suffer
the most damage.
News
from the Calving Area
Chris Slay from the New England Aquarium reported some good news in late
February 2002. Survey teams reported sightings of 15 or more right whale
calves swimming at their mothers' sides! The sightings were made from all
along the coast from Hatteras to Canaveral. Moms and calves were found up
high on the shelf, most within 10 fathoms. Many were found where they always
are, between Savannah and St. Augustine, with a strong presence off American
Beach, Florida. Chris wrote, "All babies look healthy and strong, and
15 babies is 3 MORE than the average dozen babies per year. We'll take it!"
How do they
see the whales? Most of these sightings are made from airplanes. Sometimes
researchers will tag a mother-calf pair in the calving grounds. This tag,
a radiotag, allows scientists to follow the movements of the whale. From
a boat, the researchers must be within two miles of the whale; from the
air, the researchers can be some 20 (sometimes 30) nautical miles away
from the transmitter.
2001:
Big Year for Right Whales
Recorded
Births for Northern Right Whale
(* estimated as of 3/02)
Year
|
Recorded
Births |
1996
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22
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1997
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18
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1998
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5
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1999
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4
|
2000
|
1
|
2001
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30
|
2002
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15*
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The Right whale
made big news in 2001 with sightings of 30 new calves added to the small
population. This was a record number, and whale enthusiasts were ecstatic.
Although the bumper crop of right whale calves in 2001 gave hope to many,
it turned out to be a year with a record high number of deaths as well.
Four calves died, two from ship collisions. Three adults are known dead,
and two of these were entangled. One carcass was sighted on Middle Bank,
Nova Scotia in December, the cause of death unknown.
Whales
Share Shipping Lanes: Be On Alert!
Map National
Marine Fisheries Service
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The death of
ANY right whale is very serious for the population. What are we doing to
prevent death of this species by ship strikes? These maps are an example
of efforts among many groups to protect our precious right whale population.
To help reduce the number of ship strikes, NOAA (National Oceanic and Atmospheric
Administration) and the U.S. Coast Guard have "Mandatory
Ship Reporting Systems." When ships greater than 300 gross tons
enter two key right whale habitats—the summer feeding grounds off
the northeast U.S. and the winter calving grounds off the southeast U.S.—the
ships are required to report to a shore-based station. In return, ships
receive a message about right whales, their vulnerability to ship strikes,
measures the ship can take to avoid hitting a whale, and locations of recent
whale sightings. Take
a look at the map of the Cape Cod Bay area. Do you see these three things?
The bay is
the destination for many ships that run cargo up and down the eastern
seaboard.
This shipping
lane is the same one often used by migrating right whales.
A large area
labeled "Ship Reporting System Area" is outlined on the map.
You can learn
more or read about individual sightings made in this Ship Reporting Area
by visiting this site:
NOAA
and NMFS Right Whale Sighting Advisory System (SAS)
Did
You Know?
Northern right whales are large and slow, with thick layers of oil-rich
blubber and long racks of once-valuable baleen up to 6 feet or more in length.
The whales often feed right at the surface, and they float when killed.
This makes them easy to spot and kill, so whalers called them just the "right"
whale to hunt.
Try
This! Journaling Questions
- Why do
you think the scientists can follow the whale from 20-30 nautical miles
in a plane, but only 2 miles from the boat? What might be some difficulties
of this job? Is this a career you would like to be involved in? Explain.
- The information
in the chart above shows seven years of data of the recorded births
of northern right whales. What other factors would you need to know
before you could get a better idea about this whale population?"
(Be as specific as you can.)
Copyright
2002-2004 Journey North. All Rights Reserved.
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