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Answers From the Whale Expert
(Note: The Answers below may address other species of whales besides Gray whales)
Special thanks to Anne Smrcina, Stellwagen Bank National Marine Sanctuary, for providing her time and expertise in responding to your questions!
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Episcopal High School
kfoster@ehshouston.org
Q. It is common knowledge that whales communicate by a system of high pitched noises (a.k.a. squeaks, squeals). How does the whale interpret each message? Can they differentiate between different messages based on pitch, volume, etc.? Does this apply to migration habits?
A. We're not sure how whales communicate or what they are communicating, however, we do know that different species make "vocalizations" of different types (pitch, volume, length, etc.). Humpback "songs" have been studied in the breeding grounds and appear to be a part of the mating ritual. Scientists have been able to record sounds from a variety of species, including blue whales, finbacks, humpbacks, minkes, sperm whales and orcas, among many.
Some new research sponsored by Cornell and the International Fund for Animal Welfare will be using pop-up sonar arrays in the Great South Channel to study vocalizations in the feeding grounds (and perhaps information about movement and migratory behavior). Cornell University has an interesting web page about their research utilizing the Navy's Intergrated Undersea Surveillance System which has been used to track whales over long distances in the North Atlantic.
Q. Are there any worldwide laws/treaties against the killing of whales? If
so, what are the penalties and who executes the punishments?
A. The International Whaling Commission resulted from the 1946 International
Convention for the Regulation of Whaling. About 40 nations are members in the Commission
which acts by concensus. Although most member nations agreed to stop whaling, some
nations continue to do so. There is little any nation or the Commission can do in
the form of penalties or punishment. Most action takes the form of public statements
of support of positions and public relations campaigns.
In the United States, the Endangered Species Act and the Marine Mammal Protection
Act specify civil and criminal penalties for hunting or harassing whales with some
exceptions for native subsistence hunting and research/education (primarily close
approaches for photographic purposes or skin and blubber sampling).
Q. Where do you see the right whale population going in the future?
A. We don't really know right now. If this was last year, when only one calf
was seen, most researchers would have probably given you a very pessimistic reply.
A statistical study gave an estimate of only 190 years until species extinction (if
nothing changed). This year, with a final confirmed count (according to the New England
Aquarium Right Whale Research Group) of 30 births (and three deaths), researchers
are a bit more optimistic. However, these larger birth numbers would have to continue
for several years for the population's future to be more secure. We'll have to see
over the next few years if the trend is favorable for right whales, or if this is
the wrong time for this species.
From: WASHINGTON DC
Peabody School
janmb2@yahoo.com
Q. Can whales walk on their tails?
A. I've talked to several scientists and they say that although whales have powerful tails and can hold themselves vertically in the water, they do not "walk" on their tails. Some smaller whales, such as dolphins have been trained to move backwards at the surface using undulations of their tails, but this is basically a trained behavior. Whales (right whales and humpbacks) have been seen however, standing on their heads, and using their tails as sails.
From: NEW YORK
Public School 56 Queens - The Harry Eichler School
alperstein@hotmail.com
Q. What do Right Whales eat?
A. Right whales seem to prefer small crustaceans called copepods, particularly one species called Calanus finmarchicus. These shrimp-like animals, each smaller than a grain of rice can sometimes be found in very large, concentrated patches. How the right whales find these rich food sources is unknown at this time. Scientists believe some of these patches form due to seafloor/land geography and currents, so whales might be using these oceanographic conditions to lead them to food. When right whales find a rich patch, they will "mow the lawn" so to speak. The whale will cruise through the patch (be it at the surface or underwater at some depth) with its mouth open, straining the copepods through the long, finely-fringed baleen. When the whale has a large enough amount of zooplankton collected on the baleen, it will shut its mouth and swallow.
Q. How do they mate?
A. Whales are mammals so they have similar reproductive organs as other mammals, including humans. But due to the need for streamlining (and to keep warm) in the ocean environment, organs such as the penis and nipples are tucked into the body. When male whales are ready to mate, they extrude their penises through the skin slits. Body orientation for males and females can be any which way. Either species can have its blowhole down, or they may be side-by-side. Humpback males seem to compete (with aggressive displays) until one male will "win" the "right" to mate with a female. Among right whales it appears to be a free for all, with a number of males attempting to mate with a female at the same time.
From: MISSISSIPPI
Quitman High School
dgun28@aol.com
Q. How long does it take before the whale reaches its full size?
A. Researchers estimate that a right whale reaches its full length at an age between 10-13 years, but that it continues to grow in girth (roundness and weight) throughout its life.
Q. Are the grey whales becoming extinct?
A. Gray whales, once found in extremely low numbers in the Eastern Pacific Ocean, have recovered remarkably well to the point where their numbers are at the pre-whaling estimates (over 20,000). The species, once considered endangered, has been taken off that list. Some scientists believe that there was once a population of Atlantic gray whales but that they were hunted to extinction very early in the history of whaling.
From: MAINE
gale@downeast.net
Q. Any sign of Humpbacks in the Gulf of Maine yet? Any boats going out yet?
A. The first mother-calf pair was seen in the Sanctuary on April 4th. Since then many other whales have been spotted, including other mother-calf pairs. Whalewatching has also started, with most companies offering daily trips to Stellwagen Bank (the season usually starts in mid-to-late April and extends until mid-October).
Q. Do the immature whales skip the trip to Silver Bank etc. if they aren't mating or calving?
A. Scientists believe that some immature humpback whales may skip the trip to the Caribbean and spend the winter off the coast of the mid-Atlantic states (Virginia and North Carolina) feeding on small fish. For these whales, getting fat reserves built up is probably more important than taking the trip down to the breeding grounds where they will play no active role.
Q. I was on an ecotourist boat at Silver Bank this February and as we were leaving a small whale (juvenile?) breached behind the boat several times (it was alone).
A. No one knows for sure why whales breach -- it may be a way to communicate with other whales (particularly between calf and mother in the first year), it may be a way of stunning prey (not very likely down at Silver Bank), it may be a defensive/threatening gesture, it may be a way to dislodge parasites, it may be play -- it may be a combination of these or none at all. We just don't know for sure. If this small whale was a calf or yearling, its mother was probably around somewhere close but you just didn't see her. If the whale was older than a year, it was probably on its own.
Q. Do last years calves follow their moms down even though they aren't ready to mate? If so why since they are fasting during that time?
A. Researchers believe that humpback calves generally stay with their mothers for about a year, so they would accompany her down to the calving/breeding grounds for that first year. The calves have been nursing into the summer, but begin to learn to hunt while with their mothers in the feeding grounds. Some calves split from their mothers in the fall before the migration, and some split during their stays down south. By the second summer (at age 1-1/2) the whales are usually on their own, although some pairs have been known to maintain the bond into the second year.
From: OHIO
Alliance City schools
cosma@aviators.stark.k12.oh.us
Q My name is Mark Cosma I teach at Alliance H/S in Alliance Ohio. I have a son in the the 8th grade. All he has ever spoken about are two things, playing basketball, and being a marine biologist. In regard to becoming a marine biologist...is there anything you could pass on to him? Any suggestions or direction would be greatly appreciated.
A. Marine biology is a field of study that incorporates a wide range of topics. Marine biologists may specialize in the smallest marine creatures such as bacteria and phytoplankton or they may study the largest animals on the face of the earth -- the great whales. Very often the scientists must delve into realms of biochemistry and or animal behavior. There is no simple answer to "how does one become a marine biologist." Perhaps the best advice is to go to a school with a good reputation for science. Take a wide range of studies that includes biology, chemistry, physics, biochemistry, ecology and other core science subjects. Math and statistics are also important to today's scientists. It is only after you have completed these basic courses that one should start specializing. Very often this doesn't happen until graduate school.
Advances in today's technologies for marine science require that students get a solid grounding so that they can be flexible in determining their future career pathways. (For example, whale researchers are finding that behavior may be affected by noise levels or water quality, so they have to be knowledgeable about acoustics and/or water chemistry and physiological effects of different pollutants.) Some marine biologists hardly spend any time at all at sea, while others find that they have very little home life and are often in the field. One thing we know for sure is that we are in our infancy in our understanding of the marine world. There is much to learn, and many opportunities for future marine scientists.
Stellwagen Has New Web Site- Come Visit!
Be sure to check out the Stellwagen Bank National Marine Sanctuary's new Web site, with information about Sanctuary whales, fish and other species. We hope to expand our sections on personal experiences in the Sanctuary and art/poetry about marine resources, so send us your contributions. You may find your work published on the web!
Anne Smrcina
Education Coordinator
Stellwagen Bank National Marine Sanctuary
Massachusetts
Copyright 2001 Journey North. All Rights Reserved. Please send all questions, comments, and suggestions to our feedback form
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