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ASK A SCIENTIST: ANSWERS TO QUESTIONS Mysticeti Index to Questions
Q: What is a baleen? A: Baleen is found in all whales in the suborder Mysticeti. This includes Right Whales, Blue Whales, Fin Whales, Humpback Whales, Gray Whales and others. The baleen is used to strain tiny crustaceans (shrimps) and other plankton from the water. Baleen is made up of keratin - a fibrous protein which is also found in hair, feathers, horns and fingernails. Hydroxyapatite (bone mineral) is also found in the Baleen of most Mysticete whales. Manganese, copper, boron, iron and calcium are also found in baleen in small amounts. The baleen is attached on the upper jaw of the of the whale and are flat, elongate, and attached side by side, kind of like your teeth on your upper jaw but turn your tooth 180 degrees and pack lots in side by side. When feeding a baleen whale engulfs the plankton and sea water into their mouth. They close their mouth and push their tongue to the roof of their mouth. This pushes the water and plankton through their baleen. The water is forced through the baleen and out the sides of the whales mouth, whereas the plankton gets trapped in the baleen. When all the water has been forced out of its mouth the whale swirls its tongue around its baleen, removing the krill from the baleen, and swallows them.
Question: I am currently a 2nd year Polymer Science graduate student at the Univ. of Southern Mississippi. I am doing a literature search on the material extracted from humpback whales called baleen. I specifically need information on the chemical structure of baleen and the chemistry behind how these mammals produce this material. I am also curious if any researchers have attempted to synthesize a material similar to baleen or use a biochemical process similar to how whales produce baleen in order to produce a completely different material. If you can provide any information about these matters I would be sincerely grateful. I would also appreciate any literature or researcher recommendations you may have. Thank you for time and effort. A. Baleen is found not only
in Humpback whales, but in all whales in the suborder Mysticeti.
This includes Right Whales, Blue Whales, Fin Whales, Gray Whales
and others. The baleen is used to strain tiny crustaceans and
other plankton from the water. For more information, we suggest you consult: St. Aubin, D.J, R.H. Stinson and J.R. Geraci 1984. Aspects of the structure and function of baleen, and some effects of exposure to petroleum hydrocarbons. Canadian Journal of Zoology 62: 193-198 Fraser, R.D, T.P Mcrae and G.e. Rogers. 1972. Keratins, their composition, structure and biosynthesis. Charles C. Thomas, Publisher. Springfield, Il.
A. The primary reason for the drastic decrease in the Northern Right Whale population was hunting pressure from whalers from the 1700's on. After all, the name "Right Whale" comes from the fact that they were the "right whale to catch", as they were slow moving and floated when killed! The population of Northern Right Whales, particularly in the North Atlantic, was decimated to the point where there are now an estimated 200-500 whales in the North Pacific and 200-500 in the North Atlantic. Now that they are protected, scientists are worried about the very low numbers of Right Whales. You are right in that sometimes they are hit by ships and propellers (remember, they are slow swimmers). In addition, they sometimes blunder into fishing gear, particularly in the Atlantic. The phenomenon of "incest" that you refer to is more properly called a genetic bottleneck. This happens if a population of animals is reduced to a tiny fraction of its original size, and forces related animals to interbreed. This inbreeding reduces the genetic variability of the species, makes them more vulnerable to disease, and reduces their reproductive rate. The most famous example of a genetic bottleneck is from a terrestrial animal, the cheetah (Acinonyx jubatus). The genetic diversity of the Northern Right whale is very low, and scientists think that it may be suffering the effects of a genetic bottleneck. Indeed, the effective breeding population of Northern Right whales may have been reduced at one time to 50 individuals. This genetic bottleneck and resultant loss of genetic diversity may partly explain why the Northern Right whales have not increased greatly in numbers despite the fact that they have been protected from whaling for 60 years. So, as you can see, inbreeding, or incest did not cause the drop in Northern Right whale numbers, but it may have resulted in a genetic bottleneck which has contributed to their low rate of increase in recent years. This reduction in genetic diversity is only one aspect of loss of biodiversity on our planet.
Q: The length of the right whale A: The Northern right whales measure 35 to 50 feet long,60 feet for the largest females. When calves (whale babies) are born they are 15 to 20 feet long.
Q: Where do right whales migrate to and from in the winter? A: The Atlantic Right whale (Eubalaena glacialis) migrate in the the winter to warmer temperate waters off the coast of Argentina or Cape Hatteras to give birth and mate. In these warm waters they also teach their young how to swim. In late summer and early fall Atlantic Right whales move to the poles for cooler waters. The Southern Right whale (Eubalaena australis) also migrates to the southern latitudes of their range during the summer months where the food they eat, plankton, is more abundant, and they migrate north during the winter and spring.
Q: I read on your website that the North Atlantic population of the Grey whale has become extinct, while the Eastern North Pacific population is doing quite well. Are there any plans to reintroduce Grey whales into the Atlantic? Now that the hunt has (nearly) stopped, they might have a chance.. Or are there any other reintroduction plans for regionally extinct whale species? A. As far as I know, there are no plans for any such transplant operation. Such an effort would be extremely costly, and its effectiveness would be questionable. According to conservation theories, the minimum viable population would be around 50. The relocation of that many whales would require collaboration between many countries and a very large budget. I don't believe that there is the funding, scientific, political or social support that such an operation would demand.
Q: What clings to the back of a gray whale? A. Gray whales are distinguished from other whales by the patches of barnacles that grow on their skin. Aside from barnacle patches, grey whales have patches of white, yellow and orange along their grey body that are actually concentrations of whale lice (a kind of crustacean). Gray whales feed along shorelines and travel quite slowly when they do so. This allows barnacles and lice to settle on their skin.
Q: HOW MANY BABIES DO GRAY WHALES HAVE? A: A female gray whale gives birth to a single calf (baby whale) usually every second year. There is one record of a female gray whale giving birth to twins, but twins are extremely rare.
Q: How long and wide is a whale's tail? Preferably the grey whale's tail. Thank you! A: The tail or fluke of a gray whale consists of two large flukes with a notch between them and is positioned horizontally on the whale. The tail fluke of an adult gray can measure over 3 metres (9 feet) across and weighs up to 180 kilograms (400 pounds)!
Q: I am a 5th grader doing a report on Humpback whales. we only have one day to work on them and I need some more info. on the reproduction and history of the humpback whale. What was it hunted for? oil, bones,etc....How much do the calves weigh when they are born? What do the calves eat? thanks:-) A: Although
I'm sure you can find lots of good sites on the net for information,
I'll give you a few facts that you should find useful. Calves weigh between 1-2 tons, are 4-5 meters long and feed on their mother's milk until they can eat krill and small fish on their own. More than 100,000 humpbacks have been killed by people, and although some stocks seem to be recovering, present day populations are a fraction of what they once were. Like other whales, humpbacks were hunted for meat, oil, and ivory. During breeding season, humpback males suspend themselves tail-up in the water and sing some of the longest and complex songs in the animal kingdom. Humpbacks spend the winter months in warm-water breeding grounds and go north and south to the poles to feed in the spring, summer and fall.
A. Humpback whales (Megaptera novaiangliae) are found in oceans all around the world, including the Indian, Pacific and Atlantic Oceans. They migrate from feeding grounds in polar areas (North and South) to breeding grounds in tropical or subtropical coastal areas such as Hawaii. Humpbacks are baleen whales, which means that they feed on small mid-water animals. Humpbacks have been known to feed on small fish like sardines and herring, as well as tiny crustaceans. Humpback Whales were hunted extensively in the 19th and early 20th centuries. In the mid sixties, the quotas on humpbacks were reduced by the IWC. There are about 10, 000 humpback whales left in the world today, and there is a ban on hunting them. Despite the ban on hunting, their numbers are not increasing very rapidly. This may be due to the fact that commercial fishing has removed much of their food supply from their traditional feeding areas.
Q: I am in the 10th grade and doing a report on humpback whale communication. I read the article in last months issue of national geographic and that is what gave me my idea for the report, but I couldn't find much information on the subject. It seems the only way I will find information is from scientists that are studying it. Basically why do the whales sing, and what is the effect of their singing. If you can't tell me then just give me some information on it please. A. Humpback whales have the most complex sound patterns or songs of all the whales and as a result have been quite well studied. Humpback whales produce many different types of sounds that are used for a variety of purposes (including feeding and group coordination), but their 'songs' are actually complex sequences of sounds, arranged into distinct themes or phrases that are repeated over and over for long periods of time. Each individual whale sings a song that is slightly and subtly different from the other members in its group. Dialects are also distinct between populations and sub-populations, and undergo small changes every year. Humpback whales are migratory
whales that spend the spring, summer, and fall months feeding
in colder waters, before travelling to the tropics in the winter
to breed. It is in these tropical breeding grounds where the
humpback songs are most often heard. Although no one is sure
of the function of the humpback's song, the predominant theory
is that they are sung by sexually mature males during courtship
and mating to attract females, to establish Female humpbacks can make
sounds but it is thought that they do not sing songs! Still,
the females are still not very vocal. They have been observed
making some clicks and groans probably associated with locating
the large concentrations of krill they feed on in the summer.
It is thought because the songs are mostly restricted to breeding
grounds and sung my males, they serve a reproductive function.
The songs may be a way of attracting females, gaining dominance
over other males or marking territory. To hear humback whale songs, check out this
site!
Q: How long can a Humpback Whale stay submerged A: Humpback dives usually
last 3-9 minutes (but can sometimes go for up to 45 minutes!)
followed by 4-8 blows at 15-30 second intervals.
A. In a mere 60 years of commercial whaling, Blue Whale numbers were reduced from about 200,000 to 6,000. We can see why you'd like to know about the reproductive rate of the remaining animals, as it is of critical importance to the survival of the species! Blue whales reach sexual maturity at five years. After this time, a female blue whale can have a maximum of one calf every two years. This does not mean, however, that this is the reproductive rate. Often, females will "rest" for a year, and produce, on average, one calf every three years. Over the period of commercial whaling, the rate of reproduction varied from time to time. According to George Small, in his book The Blue Whale, "During the 1930's when blue whales were hunted extensively, and their numbers began to decline, (more) females began to produce a calf every two years rather than three. The rate of reproduction remained under study, but by the mid 1950's, there were so few blue whales left that no meaningful samples of the female population were available. The exact rate of reproduction was never learned." More recent research has shown that the reduced abundance of the blue whales has had an effect on their reproductive rate. About double the historical proportion of mature non-lactating female blue whales are now pregnant (55%). In addition, the age at sexual maturity may have dropped from 5 years to 4, and the population of blue whales has more younger individuals. However, numbers of blue whales have not increased markedly in the past 20 years, even after hunting them was banned. They may need up to 200 years to recover from the devastation of commercial factory ship whaling.
Q: how many bowhead whales are out there? A: The International Whaling Commission's 1991 estimated the size of the western population of the Bowhead Whale to be 7500 whales, compared with an estimated 14,000-20,000 whales prior to commercial whaling. The Eastern Arctic population of Bowhead Whales is even more seriously depleted: only about 250 whales remained in the Baffin Island area in 1991, compared with at least 11,000 in the early 1800s. The number of Bowheads in the Hudson Bay area is thought to have been much less in 1991 than in 1860, when at least 500-600 whales summered there. Throughout the range of the species, the total population in 1991 was probably less than 10,000 whales, or about 15% of the pre-whaling abundance.
Q: What is the best estimate for the number of blue whales in the world at this time? A: Here is a list of recent
estimates for world-wide blue whales populations. I have the
feeling that exact estimates are difficult to make.
Q: During the gray whale's annual migration, how much of their body weight is lost? A: Gray whales have the longest migration route of any mammal. They migrate anywhere from 9600km to 1500km during 4-6 months. From the breeding lagoons in Baja up to the feeding grounds in the Bering Sea, gray whales will lose from 16-30% of their body weight It was originally thought that gray whales fast for the entire migration, but recent observation prove that pregnant females and smaller adults will stop in the rich feeding areas of Washington and Vancouver Island. Some whales have begun staying all summer in some on these areas. Thanks for the question!
Q: Who is threatening the Blue whales and why are they threatening them? A: Blue Whale populations
are generally thought to be on the rebound. But some factors
that may threaten their survival are:
Q: What is the general migration pattern of the Blue whale and what other web sites are there for more information on this topic? A: Blue whales are found in
all oceans of the world but are hard to track because they live
offshore most of the time and will only come inshore to feed
on large concentrations of krill. However, 3 main populations
are recognized: North Atlantic, North Pacific and Southern Hemisphere.
Blue whales general migration pattern takes them to low latitudes
in the winter to mate (such as Baja California) and to high latitudes
for feeding in the summer (as far north as the Chukchi Sea, Alaska).
A similar pattern exists in the Atlantic. There may be a permanent
population is the Indian Ocean that does not migrate (this is
still unconfirmed). There is info on blue whales at these sites:
Q: Is there any way to tell the sex of a gray whale from observing the animal on the surface? If not, how is the sex determined? A: Good question... Unless the male whale is "excited" then there is no way to tell from the surface whether a gray whale is female or male. When the male is sexually stimulated, it's hard to miss, as it measures in at 1.5m long. Normally however, it is hidden within a slit on the belly. The female sexual organs are hidden in an elongated genital slit just forward of the anus.
Q: Do bowhead whales sing? If so, do just males sing or do females sing as well? A: Yes, bowhead whales do
sing! In fact, they are one of the most vocal species of whale
out there. In some species, such as the humpback, only the males
vocalize. However, female right whales have been recorded singing "lullabyes" to
their calves. I found no information saying that female bowhead
whales do not sing, so I assume that they do! For some more great
information about bowhead whales, check out these sites:
Q: What are the potential Eco-system Effects of the Extinction of Baleen Whales A: There would be many different effects to the ecosystems if Baleen whales were to become extinct. At the very least there would be altered predator-prey relationships on the species that the whales feed on. The blue whale can eat upwards of four tons of food per day. If the whales were not eating this food it would change the predator/prey relationships drastically. It is likely that there would be some sort of population boom on the prey species of the whales. The extinction of baleen whales would also affect other parts of the ocean ecosystem. Many species feed on the carcasses of dead baleen whales and this would not happen any longer if baleen whales were to become extinct. Presently there are still many Baleen whales in the oceans but there are many endangered species.
Q: Are Humpback whales common inhabitants of Puget Sound in Washington State? A: I did some research on Humpback whales and determined that it is possible that they live in the inland marine waters of washington state. It does not appear to be part of their most travelled areas but its possible to see one. Normally Humpback whales spend their winters in the tropical oceans of the world and spend their summers in the cold and even polar oceans of the world.
Q: Can a humpback whale mother have twin calves? A: Yes a humpback whale mother can have twin calves but its a very rare event occurring about 0.39 percent of all pregnancies. Blue whales have twin calves about 0.68 percent of the time and Sei whales have twins about 1.09 percent of the time. Human mothers have twins about 1.3 of all pregnancies. Having twins is a rare event in whale species so it would be awesome to actually see it happen.
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