sagegroup-ga,
Here I will present you with the migration routes and patterns for
many of the marine mammals for which this information is known. Per
your Question’s instructions, I will de-emphasize whales and emphasize
dolphin, porpoise, seal, polar bear, otter and others. Also,in
reference to your Clarification (“What I want is reference to the
MIGRATION or NON-MIGRATION of all marine mammals”), I will also
mention those mammals that are known definitively to have no migration
patterns.
1)NARWHALS (Monodon monoceros)
The narwhal is a most intriguing subject (and one of the more
difficult ones to research due to scarcity of available data), so
let’s consider them first. You’re going to want a good map of the
Arctic Sea handy for this (and the next few mammals as well). Here’s a
link to one, from the Woods Hole Oceanographic Institute (WHOI):
[http://www.whoi.edu/media/arctic_map.html ].
From Arctic Kingdom Marine Expeditions, Inc.’s website
[http://www.arctickingdom.com/animals_narwhal_migration.htm]:
“Like many arctic mammals, narwhals migrate throughout the year
according to the advance and retreat of glacial ice. During the
winter, the narwhal vacates most of its range, wintering in Baffin
Bay, the northern Davis straight, and the mouth of the Hudson
Straight. From March through May, most narwhals follow the receding
pack ice up toward Greenland and Thule. In June and July, some
continue on into Smith Sound, while most move south and west towards
Jones and Lancaster sounds. In the autumn most retrace their spring
and summer migration route.”
Unfortunately, not all that much is known about narwhal migration
patterns, but it is known that they do migrate generally according to
the description above. They are known as “circumpolar” species,
because they travel all around the north polar region throughout the
Arctic Ocean, basically in a big circle. Narwhals live in the Arctic
Sea, north of Russia and Canada. They have occasionally been sighted
as far south as the Bering Sea, but not very often. Their migrations
take them along the circle of sea around the North Pole—from Greenland
to Baffin Bay (Northern Canada), and even as far as Eastern Siberia
and back. Little is known about what time of year these migrations
occur.
Some of the information in the above paragraph was compiled from two
book sources:
1. Cousteau’s “Ocean World,” World Pub., N.Y., 1984.
2. “The Marine Mammals of the Northwestern Coast of North America,”
Charles M. Scammon [of Scammon’s Lagoon—grey whale southern migratory
destination-- fame!], Dover publications, Inc., N.Y., 1968.
Here’s a link to a Canadian Biodiversity webpage showing a map of the
arctic with the narwhal distribution colored in blue, as well as some
information on migration:
[http://www.canadianbiodiversity.mcgill.ca/english/species/mammals/mammalpages/Mon_mon.htm
.
In fact, there is a current need recognized for further research on
narwhal migrations, as is exemplified by the following passage, from a
recent North Atlantic Marine Mammal Commission (NAMMCO)Press release
[http://www.nammco.no/fi-pr-re.htm ] :
“West Greenland Narwhal
The Scientific Committee provided research recommendations for West
Greenland narwhal to answer questions about catch statistics, stock
identity and abundance. The Council requested that the Scientific
Committee evaluate the migration patterns of narwhal in Baffin Bay and
Davis Strait.”
FYI: Davis Strait is “the narrowest point, between Greenland and
Baffin Island, NE Canada, connecting the Atlantic Ocean and Baffin
Bay.” (From Encyclopedia.com:
[http://www.encyclopedia.com/html/D/DavisS1tr.asp ].
Here’s information on a journal article published on narwhal migration
routes (although I don’t have the text of the actual paper):
“Palsbøll, Per Jakob, Mads Peter Heide-Jørgensen and Rune Dietz. 1997.
Population structure and seasonal movements of narwhals, Monodon
monoceros, determined from mtDNA analysis. Heredity 78(3):284-292.
REPRINT FILE.”
From: a NOAA page, [http://nmml.afsc.noaa.gov/Accessibility/AccLibJun98Acquisitions.html
].
Here’s another journal article reference:
“Born, E. W., R. Dietz, and R. R. Reeves, eds. Studies of White Whales
(Delphinapterus leucas) and Narwhals (Monodon monoceros) in Greenland
and Adjacent Waters. Meddr Gronland, Bioscience 39, [1995].” From
[http://www.physics.helsinki.fi/whale/literature/nfiction/nfic_b.html
].
2)BELUGA WHALES (Delphinapterus leucas)
From Arctic Kingdom Marine Expeditions, Inc.’s website
[http://www.arctickingdom.com/animals_beluga_migration.htm ]:
“Beluga's migration patterns are difficult to categorize, as there are
no distinct trend in their behaviour. Different populations seem to
exhibit different migratory patterns. While some populations stay in
small areas year round. It is known that many populations travel to
shallow river estuaries where they use the river bottoms to rub their
bodies against fine gravel during moulting season.”
Belugas are in the same family as narwhals (Monodontidae). They are
found in the Arctic Ocean and adjacent seas, in both deep offshore and
coastal waters.
From a University of Vermont webpage
[http://www.uvm.edu/whale/BelugaRangeHabitat.html]:
“Beluga whales are most commonly found in coastal waters of
circumpolar, primarily arctic regions of the northern hemisphere. Some
isolated populations however, extend into subarctic regions as far
south as the St. Lawrence River of Canada.
Since belugas are extremely difficult to monitor, population sizes are
known from only certain localities… Throughout their distribution
range belugas inhabit cold Arctic waters, living amongst pack ice in
winter and in shallow bays and estuaries of large northern rivers in
the summer… Belugas are adapted to cold and ice and frequently inhabit
areas where pack ice is common, although they are limited seasonally
to areas where they can maintain breathing holes.”
So, Belugas are similar to the narwhals, except that the narwhals can
endure iced-over water since they have the large tusk to break through
the ice. This certainly affects their migratory behavior.
Here is NOAA’s overview on beluga while migratory behavior:
“Beluga whales are distributed throughout seasonally ice-covered
arctic and subarctic waters of the Northern Hemisphere (Gurevich 1980)
and are closely associated with open leads and polynyas in ice-covered
regions (Hazard 1988). Five stocks of beluga whales are recognized
within U.S. waters: 1) the Cook Inlet stock, 2) the Bristol Bay stock,
3) the Eastern Bering Sea stock, 4) the Eastern Chukchi Sea stock, and
5) the Beaufort Sea stock. During the winter, beluga whales occur in
offshore waters associated with pack ice. In the spring, they migrate
to warmer coastal estuaries, bays, and rivers for molting (Finley
1982) and calving (Sergeant and Brodie 1969). Annual migrations may
cover thousands of kilometers (Reeves 1990). Some, if not all, of the
Cook Inlet stock may inhabit Cook Inlet year-round (Hansen and Hubbard
1999), while the other stocks winter in the Bering Sea."
Here’s a link to the National Oceanic and Atmospheric Administration’s
(NOAA) “Beluga Whale Home Page”:
[http://nmml.afsc.noaa.gov/CetaceanAssessment/BelugaWhale.html ].
Let’s stick with the Arctic for now, and go to #3 on my list,
3)POLAR BEARS(Ursus maritimus)
Here’s a concise description of polar bears’ migratory patterns, from
Arctic Kingdom Marine Expeditions, Inc.’s website
[http://www.arctickingdom.com/animals_polarbear_migration.htm]:
“Polar bears spend much of their lives traveling, sometimes traveling
as far as three thousand miles in search of food. During the summer
months, bears follow the shifting pack ice, roaming up to 125 miles
offshore. In the autumn, polar bears move south with the advancing
ice. In October or November, pregnant females enter their dens. Some
dens are used over and over, and some females will even return to the
dens they were born in. Family groups remain in their dens until March
or April.”
Polar bears range throughout the coastal areas and islands of the
Arctic, polar bears live in harsh conditions with temperatures well
below freezing. Their habitat spans Greenland, Norway, Russia, Canada
and Alaska. [From http://216.239.33.104/search?q=cache:VxIouu2diDwJ:www.nwf.org/productions/bears/pdfs/polarbear.pdf+Ursus+maritimus++migratory+routes&hl=en&ie=UTF-8
].
Also, keep in mind that polar bears are indeed bears, even though they
are highly aquatic, and so they do hibernate. From the same site:
“Polar bears hollow out winter dens in protected snowbanks, where
females den
from November to March, during which time they give birth. Males den
for much shorter periods, usually from late November to late January,
but may be up and about occasionally at any time of the year. Cubs
remain with their mother about a year and a half, denning with her the
winter after their birth.” So, their migratory patterns are based on
their hibernation behavior.
4)WALRUS (Odobenus rosmarus)
From Arctic Kingdom Marine Expeditions, Inc.’s website
[http://www.arctickingdom.com/animals_walrus_migration.htm]:
“Walruses are migrating animals. Their spring migration follows the
pack ice and the animals search out open water areas while heading
north. The animals mostly migrate by swimming but they may also catch
a ride on an ice floe once in a while. The Atlantic walrus is thought
to travel less than the Pacific walrus.”
So, walrus migration patterns can be influenced by ice floe drift
patterns, which throws a monkeywrench, so to speak, into efforts that
attempt to precisely calculate their collective movements season after
season.
5) BOWHEAD WHALES (Balaena mysticetus)
From Arctic Kingdom Marine Expeditions, Inc.’s website
[http://www.arctickingdom.com/animals_bowhead_migration.htm]:
“Bowheads migrate according to the formation and movement of sea ice,
travelling north in the summer and south in the winter. Bowheads
prefer to live and feed amongst the ice. Baby bowheads are born during
the spring migration, and must therefore be able to follow the herd
from birth.”
Alright, let’s move down to somewhat warmer waters.
6) SEA OTTERS (Enhydra lutris)
From an Alaska Forestry Service webpage [
http://www.fs.fed.us/r10/ro/naturewatch/species/seaotter_frame.html ]:
“Sea otters usually do not migrate. They seldom travel far unless an
area has become overpopulated and food is scarce. They are gregarious
and may become concentrated in an area, sometimes resting in pods of
fewer than 10 to more than 1,000 animals. Breeding males will drive
nonbreeding males out of areas where females are concentrated.”
And, from the same page:
“Perhaps as few as 2,000 total animals existed in 1911, but by the
mid-1970s the Alaska population numbered between 110,000 and 160,000.
Most of the sea otter habitat in Alaska has now been repopulated. The
principal exception is Southeast Alaska where numbers are increasing
rapidly and otters are moving into new areas. Smaller populations
exist in the Commander and Kurile islands, British Columbia,
Washington, and California.”
So, sea otters don’t really migrate in the true sense, but may be
driven to relocate long distances in extreme circumstances, but this
is not a true “migration,” which implies seasonality.
7) ATLANTIC BOTTLENOSE DOLPHINS (Tursiops truncatus):
Atlantic bottlenose dolphins, and indeed all bottlenose dolphins are
not a migrating species. They are found in all world oceans except the
Arctic, and may travel long distances in response to prey distribution
or sea temperature changes, but there is no regular seasonality to
these types of movements.
From a “WhaleNet” message board
[http://whale.wheelock.edu/archives/ask00/0191.html ] :
(Note: the following description is also a very good treatment of the
concept of “migration” in general as it applies to any animals,
including marine mammals).
“As a species, bottlenose dolphins do not migrate like many
baleen whales do. When we talk about movement patterns of dolphins, we
do
not say that they migrate, but that they 'move'. Migration implies
that its
something done every year by the whole species, which is not what
happens
with bottlenose dolphins. But, this is usually a matter of preference,
and
depends on the scientist.
At the northern limit of the bottlenose dolphin's range in the western
North
Atlantic, bottlenose dolphins are seasonally migratory, with a more
southerly distribution in the winter. Along the California coastline,
bottlenose dolphins respond to changes in distribution of prey and
move
along the coastline.
We know that bottlenose dolphins are capable of making very long
trips. For
example, a bottlenose dolphin in Argentina made a 600-km roundtrip.
Recently,
two bottlenose dolphins that stranded in Florida were satellite-tagged
and
tracked. One dolphin covered 2,050 km in 43 days, whereas the other
dolphin
covered 4,200 km in 47 days.
Honestly, we really don't understand bottlenose dolphin movements all
that
way, but we're getting a better handle on it. But, again, bottlenose
dolphins are not like a baleen whale, moving from one big geographic
location to another.”
Here’s a link to the WhaleNet home page (it offers a wealth of
information on whales in general, including migration):
[http://whale.wheelock.edu/Welcome.html ].
8) NORTHERN OR STELLER SEA LION (Eumetopias jubatus)
Many sea lions and seals are not truly migratory, but the Stellar
sea-lion is one of the few that does exhibit some migratory behavior.
From [http://ourworld.compuserve.com/homepages/jaap/sealion1.htm#Top
]:
“The range of this species is from the Sea of Japan at 43°N, north to
the Pacific rim at 66°N and then south the North American Pacific
coast to San Miguel Island at 34°N. Some migration seems to occur. On
the Oregon coast, Northern sea lions and California sea lions live
together in caves.”
The following link is to the U.S. Fish & Wildlife Service page for
Steller sea-lions, and offers extensive links to further resources:
[ https://ecos.fws.gov/species_profile/SpeciesProfile?spcode=A0FS ].
9) CALIFORNIA SEA LIONS (Zalophus californianus)
The males of these animals are migratory. Here is more detailed
information, from [http://www.imma.org/pinnipeds/Californiasealn.htm
], an International Marine Mammal Association (IMMA) webpage:
“California sea lions are found in nearshore waters along the Pacific
coast with rookeries off the west coast of Vancouver Island, to Baja
California. Two offshore hauling out islands also exist off the tip of
Guadalupe Island and Rocas Alijos. Hauling out grounds north of
southern California are occupied by males only, who migrate north for
the winter. During the migration, some animals also enter the lower
reaches of coastal rivers in northern California, Oregon and
Washington. Another population inhabits the Gulf of California..”
Here’s a link to IMMA’s home page (for future reference):
[http://www.imma.org/ ].
10) HARBOR SEALS
Special Note: there are two sub-species of “Harbor Seals,” one U.S.
west Coast species, and one U.S. east coast and European species.
Interestingly enough, the western sub-species is non-migratory, while
the eastern sub-species is migratory to some extent. The following
link is to M.L. Torok’s ( biology graduate student) Geocities website
dedicated to both sub-species of Harbor Seals:
[http://www.geocities.com/RainForest/4562/hsinfo.html ].
a) Phoca vitulina richardsi (Pacific Ocean)
Harbor seals are a true seal found along the California coast, and do
not migrate.
The following paragraph is from the Bergen County Technical School’s
“Harbor Seal Home Page”
[http://www.bergen.org/Smithsonian/HarborSeal/HSBehavior.htm ]:
“Harbor seals are not migratory. Despite the ability to travel great
distances, most Harbor seals stay near their birthplace. Tagging
studies indicate that at least some animals may move long distances,
both along shore and off-shore. They haul out on remote beaches, tidal
mud flats, offshore rocks and reefs, glacial and sea ice, and objects
such as buoys and log booms to rest, pup, and molt.”
Excerpt from [http://pt-lobos.parks.state.ca.us/nathis/MarineMam.htm
]:
“Harbor seals are here [California] year-round and do not migrate.
They pup in April. Mating occurs when the pup is weaned, up to 6 weeks
after birth.”
Here’s a comprehensive general info page on harbor seals, including
photos (from : [http://www.cresli.org/cresli/seals/hbrseals.html ].
b) Phoca vitulina concolor (Atlantic Ocean)
Here’s a summary of Phoca vitulina concolor migration activity, from
this Coastal Research and Education Society of Long Island, Inc.
(CRESLI) webpage:
[http://www.cresli.org/cresli/seals/hbrseals.html ]:
“Harbor seals, like most other seal species, migrate southward every
winter, returning to New England and Canada in the summer. On Long
Island a large influx of these seals arrive in November and remain
through mid- May, although some are thought to stay throughout the
year."
Note it references “most other seals” as being migratory in general.
11) DALL'S PORPOISE (Phocoenoides dalli)
This animal is not truly migratory, but moves over extremely vast
expanses of ocean. The following information was obtained from the
American Cetacean Society’s Dall’s Porpoise Fact Sheet page
[http://www.acsonline.org/factpack/DallsPorpoise.htm ]:
“DISTRIBUTION AND MIGRATION
Dall's porpoise is found only in the North Pacific, ranging from Baja
California north to Alaska and the Bering Sea and across into Japanese
waters, seemingly confined to colder waters with temperatures of less
than 60 degrees F (15 C). Many are year-round residents over much of
their range.”
By itself, I would take this to mean that they’re not truly migratory,
although they have a very large range and travel extensively through
it, probably driven by prey distribution. However, as we’ve seen with
other marine mammals, there are observations to support that *some*
regional-specific groups of the species exhibit migratory patterns in
certain parts of the range, but not all. From a Walker’s Mammal’s of
the World webpage [http://www.press.jhu.edu/books/walker/cetacea/cetacea.phocoenidae.phocoenoides.html
]:
“In the western Pacific there is a well-defined annual migration in
which most Japanese animals shift northward for the summer to the Sea
of Okhotsk and the Kuril Islands. In the eastern Pacific there are
apparently no large-scale migrations, and large numbers of
Phocoenoides remain throughout the year from Alaska to California.
There is, however, a tendency for concentration near the shore and to
the south during the fall and winter, and offshore and to the north in
the spring and summer. Such seasonal movements are probably related to
distributional changes in prey organisms (Kasuya 1978; Leatherwood and
Reeves 1978; E. D. Mitchell 1975a; Morejohn 1979; U.S. National Marine
Fisheries Service 1978).”
So, one can see how this can get to be quite a complex topic.
12) NORTHERN ELEPHANT SEALS (Mirounga angustirostris)
These incredibly large marine mammals have some of the most
spectacular migrations of all! The following passage is from a NOAA
sanctioned website on Northern Elephant Seals
[http://nmml.afsc.noaa.gov/education/pinnipeds/nelephant.htm ]:
“The northern elephant seal is the only mammal known to make two long
distance migrations in a year. They travel from their breeding
colonies in Mexico and California to Alaska or the north Pacific Ocean
to feed and then return to their breeding colonies to molt 2 to 6
months after breeding. After they molt they travel back to their
feeding areas and return again to their breeding colonies to breed 6
months later. They may travel up to 21,000 miles in a year, the
longest migration known for any mammal.”
Now, be sure and visit the actual link I pasted above, because the
word “migrations” in the first sentence of the paragraph above is a
link which displays a pop-up migration map detailing Elephant Seal
Movements as an example of their migratory routes.
Here’s a link directly to the pop-up migration map (Note: I can’t
guarantee the pop-up map link will work outside of their site, so if
you have any trouble, go to the main link above and click on the
“Migrations” hyperlink from there):
[ http://nmml.afsc.noaa.gov/education/pinnipeds/popnemigration.htm ].
13) MANATEES (Trichechus manatus), (Order Sirenia)
This is the so-called Caribbean or West Indian Manatee. There are also
African and South American (Amazon River) species as well. These
animals do migrate.
From the Florida Power & Light (FPL) Manatee Page [because manatees
like to congregate around the plant’s hot-water effluent
areas]--[http://www.fpl.com/environment/endangered/contents/the_west_indian_manatee.shtml
]:
“In the winter months, cold weather shortens their northernmost range
to Florida, while in the summer, some swim as far north as Virginia
and as far west as Texas. In a few cases, manatees have been observed
to cover over 520 miles, each way, during their migrations. One
manatee was known to swim 143 miles in only four days!
The West Indian manatee lives primarily in shallow, slow-moving river,
saltwater bays, canals and coastal areas - especially where sea grass
beds can be found. But in winter months, where the temperature dips
below 68°F, manatees seek warm-water locales such as FPL's Riviera
plant.”
Here is a link to a highly scientific treatment of manatee migrations,
titled, “Seasonal Residency and Movements of Manatees Near Sarasota,
Florida”:
[http://members.aol.com/adrcnet/1998/1998sp32.html ].
Okay, by now we’ve journeyed around the world, and in the process
covered over a dozen marine mammals representing all the major types
(whales, dolphins, porpoises, seals, sea-lions, walrus, manatees and
even polar bears). At this point I’ll cover the search strategies I’ve
used, and in the process point you to additional resources.
Google search strategy:
Keywords:
If you’re looking for more information or data on a particular species
(such as those I’ve covered here), I’ve found that what gets the best
results is to enter both the common name AND the scientific name
followed by the word, “migration” into the search box. For example,
“Manatees Trichechus manatus migration,” or “narwhals Monodon
monoceros migration.” That’s why I provided the scientific name for
each species I’ve treated here (in addition to clarifying exactly
which animal I’m referring to, and giving you more complete
information). Also, clicking the “similar links” gray colored link
next to each search result main link will bring you to more content
similar to that of the last link.
If you ever need extremely detailed data on something very specific,
it’s best to email an authoritative source directly and request the
information, such as someone at NOAA. Many of the links I’ve provided
here are to various NOAA pages.
Now, for some other keyword searches that proved useful to me and may
to you:
“marine mammal migrations”:
://www.google.com/search?hl=en&ie=UTF-8&oe=UTF-8&q=%E2%80%9Cmarine+mammal+migrations%E2%80%9D&btnG=Google+Search
,
“marine mammal migratory routes”:
://www.google.com/search?hl=en&lr=&ie=UTF-8&oe=UTF-8&safe=off&q=marine+mammal+migratory+routes&btnG=Google+Search
,
“marine mammal migration data”:
://www.google.com/search?hl=en&lr=&ie=UTF-8&oe=UTF-8&safe=off&q=marine+mammal+migration+data&btnG=Google+Search
,
I hope this information is what you’re looking for. If anything I’ve
written here is unclear, or if I’ve left anything out that’s important
to you, such as information for a particular species, please let me
know and I’ll Clarify the answer.
Sincerely,
omniscientbeing-ga
Google Answers Researcher |
