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answers to Mammals questions!

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ASK A SCIENTIST: ANSWERS TO QUESTIONS

Odontoceti
"Toothed Whales"

Index to Questions


 DOLPHINS
Pacific Bottlenose Dolphin Range
Dolphin Brains
Colour Vision in Bottlenose Dolphins
Dolphin Births
Dolphin Music?
Dolphin Longevity
Dolphin Intelligence Papers
Do Dolphins Hibernate/ Migrate?
Communicating with dolphins
Dolphin Tails
Dolphin mortality and tuna
Dolphin Sleep
Dolphin and human genetic relatedness
Dolphin signature whistles
Captive Dolphin Release
Sleeping Dolphins
Dolphin food, diving
Dolphin Blowholes

Relationship Between Sharks and Dolphins
Dolphin/Human Physiology
Tool-using Dolphins

Dolphin Sex
Dolphins and the Titanic
Dolphins's Age
Dolphin bellybottons
Are dolphins bald?
Dolphin Genders
River Dolphins
Dolphin Pox
Dolphin Senses
Dolphin Strandings
Cows and Dolphins
Dolphin Age Distinctions


 KILLER WHALES

 Killer Whale Markings
Whatever happened to A57?
Orca Questions
Orcas and pollution
Orca Rubbing Beach
Orca Classification
Orca colouration
Orca Nickname
Orca White Eye Patches
Measuring Orca Populations
Orca Lifespan
Pioneer killer whale research
Orcas in California
French word for Orca
Returning Orcas to the wild
Killer whale localities
Orca Endangered?

Offshore Killer Whales
Killer Whale Skeletons
Where to work with and learn
more about Orcas?
Why Orca Fins Flop Over
Killer Whale Echolocation
Do Killer Whales Eat Humans
Captive Killer Whale Behaviours
How Orca Calves Are Born
Why Orcas Sing
A White Orca
Killer Whale Mating
Killer Whales living in Fresh Water
Are Orca's Dolphins?


 BELUGAS

Beluga Songs
Endangered Belugas?
Green Beluga
Pollution and Beluga whales
What a Beluga Does in a Day
How did the beluga get its name, and other questions


NARWALS

Narwhals
Narwhal info
Narwhal Tusks
Narwhal's horn
Narwhal relationships


 TOOTHED WHALES

Bairds Beaked Whale
Sperm Whales
Blackfish
Ambergris in Sperm Whales
Giant Squid vs. Sperm Whale
Whale or dolphin?


 DOLPHINS

Pacific Bottlenose Dolphin Range - Received Jan. 6/00 from Maxwell Kelly in Northern Alberta, Canada

Q: I was wondering if the Pacific Bottlenose Dolphin lives up around Vancouver. If not, how far North do they come?

A: The Pacific Bottlenose Dolphin does not live around Vancouver. The range of the bottlenose dolphin in the Pacific Ocean starts in southern California and northern Japan and extends to southern Australia, New Zealand and Chile.

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Dolphin Brains - Received from Dodie in California.

Q. What is the size & capacity of the frontal lobes in a bottle nose dolphin. I want to compare it with the human brain frontal lobes. Do dolphins have two sides to their brain like humans? If they do, do you know which side they operate from most often...whether it be their right side or left side?

A.
A comparison of the actual weight of brains is not normally used to compare species, due to the variation in the sizes of the animals. The weight of the brain as a percentage of body weight is about 1.9 % in humans, and varies between 0.25% and 1.5% in toothed whales (with the dolphin being at the higher end of the spectrum). Perhaps a better measure of comparing mental development between species is the Encephalization Quotient (EQ) which is the ration of the brain volume to body surface area. The EQ of humans is 7.4, of Chimpanzees 2.5, most other mammals less than 2.0. The EQ of the bottle nosed dolphin is 5.6, the highest value of all whales.

It is believed that dolphins have the ability to put one half of their brain asleep while resting. This allows them to remain alert. They then can switch 1/2's and rest the opposite side. More information about this topic may be found in "The Bottlenose Dolphin" Edited by S. Leatherwood and R.R. Reeves. San Diego: Academic Press, 1990. There is a chapter on "The Central Nervous System of the Bottlenose Dolphin"(pp. 69-97) by Sam Ridgeway. It also has an extensive reference list if the information wanted is not there. There is a more extensive discussion of this possibility in this chapter.

Reviews of cetacean brains may be found in :

Ridgeway, 1986 Dolphin Brain Size. In: Bryden, M.M and Harrison, J.R. (eds.), Research on Dolphins, Claredon Press, Oxford pp 59-70.

Morgane et al. 1986. Evolutionary aspects of cortical organization in the dolphin brain. In: Bryden, M.M and Harrison, J.R. (eds.), Research on Dolphins, Claredon Press, Oxford pp 71-98

Morgane et al. 1986. Evolutionary morphology of the dolphin brain. In: Schusterman, R. J., Thomas, J.A. and Wood, F.G. (eds.), Dolphin Cognition and Behaviour: A comparative approach, Lawrence Erlbaum, Hillsdale NJ, pp 5-29..

Answered by Treva Ricou

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Colour Vision in Bottlenose Dolphins - Received Nov.6/99 from Alex Drozd in Pittsburgh, PA

Q: Do bottlenose dolphins see in colour or in black and white? Thank you.

A. Dolphins can see some colours, however seeing a full spectrum of colour is not as important for water animals as it is for land animals. At the surface of the ocean all the colours can be seen, but in deeper water everything appears blue-green. Down at about 200 meters there is no colour left at all, the sea is pitch black. So although at the surface its important for dolphins to see some colours, they are a diving animal and spend a lot of time down in deeper waters, so being able to see in colour isn't as important.

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Dolphin Births - Received from Allisha in Kansas.

Q. When is a good time to see a Dolphin being born?

If you are talking about seeing a dolphin being born in an aquarium, this can happen at just about any time of the year. Aquarium staff know if one of their dolphins are pregnant, and usually will let the public know if one of their animals is "expecting". Usually though, members of the public are not allowed to actually witness the birth of a dolphin.

Not many people have been lucky enough to see a dolphin being born in the wild. Unlike the baleen whales like the grey whale or the humpback whale that have a distinct breeding cycle, dolphins, along with other toothed whales, do not have as distinct seasonality in mating and birth. This means that there is no distinct place or time when you could say for sure that dolphins were being born in the wild.

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Dolphin Music? - Received from Michelle in Los Angeles.

Q: Is the noise that dolphins produce, is is art(ie.music) or a way for them to comminicate?

A.
Dolphins (along with whales) certainly do make a variety of sounds underwater. These sounds are used primarily to communicate, and also may be used as a kind of "sonar" to detect objects underwater. See the question on Whale Communication on this page for more information.

About dolphins and music: It has never been shown that dolphins make noises strictly for their own pleasure. Of course, human artists have incorporated whale and dolphin sounds into their own musical work.

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Dolphin Longevity - Received from Peter in Missouri.

Q How long does the average dolphin live?

A.
It's sort of hard to say what the "average" dolphin is, since there are 32 species of oceanic dolphins (Delphinidae family) and six porpoise species (Phocoenidae family). There are five river dolphin species (Platanistoidea family) found in five different rivers.
In general, smaller species live shorter lives than larger ones. The small, harbour porpoise is thought to live about 15 years, The bottle-nosed dolphin for 25 years, and the killer whale (which is in the dolphin family) for 50+ years for males and 80+ years for females.

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Dolphin intelligence papers - Received Jul.23 from Louie in the Northeast

Q: Where can I find some specific research on the intelligence of dolphins. I am doing a paper contrasting their intelligence with that of humans. Thank you

A. I looked around a little bit, and a few names popped up. Quite a bit of work was done in the mid-60s on dolphin intelligence in conjunction with the US Navy Dolphin Program. If you search the internet using DOLPHIN INTELLIGENCE, you will find several pages that discuss some of these experiments and their possible implications. Herman, Markey, Batteau and Pryor are names that come up often in the material that I have read. You may want to try doing a journal search using these names. The Cambridge Scientific Abstracts page is a useful one for journal searches. It can be found at http://www.csa.com, and your home university should have a subscription (you need a username and password). So try some of these places and let me know what you come up with. Good luck.

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Do Dolphins Hibernate/Migrate? - Received from Mike in Indiana.

Q: Do dolphins migrate or hibernate (either or neither)?

A.
No, dolphins do not hibernate - in fact they can only sleep for relatively short periods of time, as they must rise to the surface and take a breath occasionally.

In general, dolphins do not migrate, at least not the same way that the Gray Whales migrate from Baja California northward up the West coast of North America, or the way that Humpback Whales migrate yearly from feeding grounds in Northern seas to breeding areas in tropical seas. The susu, or Ganges River Dolphin does "migrate" in that it is confined to main river channels during the dry season, and then disperse into tributaries and creeks when the yearly rains come.

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Communicating with dolphins - Received from Amara in Missouri.

Q Do you think that someday we will be able to communicate with dolphins? If so how?

A.
The term "communicate" can have a very broad definition. Communication in animals can be very simple (eg. birds using song to communicate that they own a territory, or a butterfly using bright colours to communicate to birds that it tastes bad). It can also be more complex (eg. wolves communicating with each other while hunting). Communication can be defined as the process of transmitting a message to another animal. In fact, you could say that we communicate with our dog when we send it to fetch a ball.

Various experiments have shown that dolphins are capable of quite complex communication. Dolphin make a wide variety of sounds, some of which have been shown to be used in social situation. Courtship, distress, and aggressive confrontation all have their own particular sounds associated with them. Other sounds may be used to identify particular animals, and to keep groups together while foraging. Dolphins can also learn to mimic sounds very rapidly and accurately.

Louis Herman and his colleagues in Hawaii have worked extensively with the subject of language and two way communication with dolphins. They have shown that dolphins are capable of understanding simple auditory or gestural language elements even when they are combined into two-word or three-word sentences. Dolphins trained to respond to these commands have then been shown to be able to report to other animals that a particular object is present or not in their tank. These and other studies show that dolphins are capable of communicating complex concepts.

However, dolphins may not use these abilities in the wild. All attempts to demonstrate the existence of a "natural language" in dolphins has been unsuccessful. It appears that while we may be able to communicate to a certain extent with specially trained dolphins, we will not be able to actually have a conversation with them.

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Dolphin tails - received June 24/00 from Harry in Chicago.

Q: Are Dolphin Tails real tails (vertabrae (sp?) column) where are the legs? Do some marine mammals have the legs adapted/evovled into tails ?

A: Yes, dolphin tails are true tails extending from the vertebrae column.

Some cetaceans (whales and dolphins) have remnants of the pelvic bone in their bodies that do not seem to have a function. This bone is evidence of the cetaceans' evolution from an ancestral 4-limbed ancestor.

There is mammal known to have evolved a tail from legs.

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Dolphin mortality and tuna - Received from Shelley in Missouri.

Q: About how many dolphins are killed a year by tuna nets or by people catching them accidentally?

A.
Dolphin mortality from the tuna fishery has dropped dramatically since the 60's, when it was estimated that 100,000 or more dolphins were killed in fishing nets each year. Because of better fishing practices, this figure has been reduced by 96%. Last year, there were only about 4,000 (some reports say 3,609) dolphin deaths caused by tuna nets.

For two very opposing views about the future of tuna fishing and what we should do about dolphins being caught in nets, see the High North site in Norway and the Planet ARK site in Australia.

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Sleeping dolphins - Received Sept. 15 from the Fifth Grade Class at H.E. Corley Elementary School.

Q: We were surfing the net looking for information about dolphins and came upon your website. We were interested in knowing why dolphins do not stay at the surface when sleeping.

A: Sleep or rest in wild schools of dolphins is not commonly observed. Biologists believe that when dolphins sleep, one half of their brain is kept alert while the other half is resting. One reason for this is because, unlike humans, breathing in dolphins is voluntary and not under the automatic control of the central nervous system. A typical sleep pattern for dolphins appears to consist of slowed swimming, aggregation of school members into a more tightly packed group and changes in diving rhythms.

A study of spinner dolphins (Stenella sp.) demonstrated that just before a rest period, the dolphins swim inshore from deep water feeding grounds. Once in the rest area, the group slows down and the dolphins move closer together to the point of actually touching. As opposed to shallow diving in the active school, the resting school exhibits deeper dives of longer duration. Surface times are significantly reduced, with the dolphins only coming up for a few breaths and then quickly re-submerging. It is believed that this behaviour serves to reduce the risk of predation on the resting group. If the dolphins remained at the surface while resting, they would be a more obvious target for predators.

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Dolphin and human genetic relatedness - Received from Bill in New Jersey.

Q: I am trying to find out all that I can about dolphins and humans and how they are genetically related (if we are)? any help would be much appreciated.

A. All animals are genetically related to each other in some ways. Some animals are more closely related to humans than others. For example, a mouse (mammal) is much more closely related to a human (mammal) than is a clam (mollusc).In terms of how "related" two animals are, you really have to consider the level that you're looking at. For example: Dolphins are mammals, so they are genetically more related to humans than clams are. If you are looking at how dolphins and humans are related compared with all of the different mammal groups, you'll find that they are not very closely related. Often, biologists will construct a "cladogram" to show how different groups of organisms are related. It is a branching structure - related groups are shown closer together. In a cladogram of the different mammal orders, humans (primates) are closely related to orders such as Chiroptera (bats), and Insectivora (shrews, moles, hedgehogs). Porpoises are in the order Cetacea, and are more closely related to the order Artiodactyla (deer, cows, etc.)

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Dolphin signature whistles - Received from James in Kingston, Ontario.

Q: Hello, I'm working on a project at Queen's University in Kingston, Ontario. The project entails the evolution of communication systems within dolphin species. In particular, I would like to know if you have any information dealing with'signature whistles'. I am trying to determine if the 'last name' of the signature whistle is genetically determined, or if it is learned (passed down from the maternal parent).

A. In the bottle nosed dolphin, the mother often whistles continuously shortly after birth. This whistling may go on for several days. Initially, the mother's whistle is quite uniform, but then it acquires a "signature" characteristic which is presumably used for individual recognition. If this "signature" was genetically determined, the mother would have no need to whistle continuously to her offspring right after birth. She does this presumably in order to "teach" her offspring the signature. Many animals including birds and mammals use individual vocal recognition to maintain parent-offspring bonds. While the ability to quickly learn to recognize a specific individual vocalization may have some genetic basis, the young animal is not born recognizing its mothers vocalizations - learning must still take place.

For more information, see:

Caldwell, M.C. and Caldwell, D.K. 1979. The whistle of the Atlantic bottlenosed dolphin (Tursiops truncatus) - Ontogony. In Winn, H.E. and Olla G.L. (eds.), Behaviour of Marine Animals vol 3: Cetaceans, Plenum Press, New York, NY, pp. 369-401.

Herman, L.M. and Tavolga, W.N. 1980 The communication systems of cetaceans, in: Herman L.M. (ed.), Cetacean Behaviour, Wiley Interscience, New York, NY, PP 149-209.

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Dolphin food and diving- Received from West Virginia.

Q: 1) How far down can a Dolphin Dive? 2) What do dolphins eat?

A.

1) There are many different species of dolphins. The depth that they dive to generally depends on what sort of fish they usually eat. A river dolphin such as the Ganges Susu would not have to dive as deeply to get fish as an Atlantic White sided dolphin. Dolphins usually don't dive very deep, and certainly don't hold the record for cetaceans. The sperm whale has been known to dive as deep as 3000 meters!

2) Again, there are many species of dolphins, and they eat a wide variety of types of fish.

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Dolphin blowholes - Received Aug. 20 from Jenna.

Q: Do dolphins breathe with both their blowhole and their mouth?

A: All cetaceans (whales, dolphins and porpoises) breathe only through their blowholes, which are situated on or near the top of the head. Blowholes are similar to nostrils in other mammals, serving as openings to the respiratory passages. Baleen whales (e.g.: humpback and gray whales) have two blowholes side-by-side, while toothed whales (e.g.: dolphins and sperm whales) have only one blowhole. Cetaceans cannot breathe through their mouths, because the trachea (air passage) and esophagus (food passage) are completely separate. The trachea connects only to the blowhole.

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Relationship between sharks and dolphins - Received Aug. 30 from Lisa in Los Angeles.

Q: Please tell me about the relationship between sharks and dolphins. I am specifically interested in whether dolphins attack sharks and how they interact.

A: Dolphins and sharks are both top-level predators in the marine environment. Its difficult to generalize about interactions between these organisms because there are so many different species of sharks and dolphins, so instead I'll provide a couple of specific examples.

A study of bottlenose dolphins (Tursiops truncatus) off Natal, South Africa determined that approximately 2.2% of the dolphin population were preyed upon by sharks. An additional study of a T. truncatus population in the northern Adriatic Sea found poor evidence of shark predation. However, when considering calves and juvenile dolphins the mortality rates appear much higher. A study of dolphins in Shark Bay, Western Australia demonstrated that 35% of calves did not survive past the first year, while 50% of the remaining juveniles did not survive past weaning. The main cause of death was believed to be heavy predation by tiger sharks (Galeocerdo cuvier), as demonstrated by the high incidence of shark scars on adult dolphins.

One of the only documented instances of a dolphin attacking a shark occurred in late 1997 off the coast of the Farallon Islands. A female killer whale (Orcinus orca) attacked and killed a small great white shark, although she did not consume it. Biologists believe this is an isolated incident, and not indicative of typical interactions between sharks and killer whales. There are two first-hand reports of this incident on the Shark Research website.

(Thanks to Hugh Finn for assistance with this answer)

References:

Bearzi, G., G. Notarbartolo-Di-Sciara and E. Politi. 1997. Social ecology of bottlenose dolphins in the Kvarneric (northern Adriatic Sea). Marine Mammal Science, vol 13, no 4, pp. 650-668.

Dudley, S.F.J. and G. Cliff. 1993. Some effects of shark nets in the Natal nearshore environment. Environmental Biology of Fishes, vol 36, no 2, pp. 243-255.


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Dolphin/human physiology - Received Sept. 21 from Erin in Upstate NY.

Q: I have to write a paper at school about Human Physiology. I would like to find out any information about the study of Dolphins used interchangably with the Human Physiology. Please give any information that you can, including possible web sites where I can access any information that I need. Thank you.

A: I assume that you're looking for information on the comparative physiology of humans and dolphins (e.g. comparisons of visual acuity or hearing abilities). Quite often, general books on mammalian physiology will have this type of information. Head down to your university/college library and search the indexes, in addition to looking for journal articles using Biological Abstracts. Ask at the reference desk if you need help using the databases.

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Tool-using Dolphins - Received Jan. 18 from Trish in Oregon

Q: I have to write a research paper for my biology class dealing with animal biology. I found an article in the searchbank at the college about dolphins with a cone-shaped sponge over its beak in Shark Bay, off Western Australia. The article was in Discover, March 1998 v19. It's really vague. I'm having trouble finding any other articles pertaining to this one. There are million's of articles about dolphins but not the "Shark Bay dolphins". Can you help?

A: Well, I can try. I found the article on line, and read it over (by going to the Discover web site and searching the archived issues for "sponge" for that issue). I seems to me that scientists can only speculate as to why these dolphins exhibit this behaviour. They seem to think that they use the sponges as protection against the poisonous spines of stonefish and stingrays. Another speculation is that the sponges could be used to stir up prey from the sea floor while avoiding these stings. If you use a search engine and look up "shark bay sponge" you may come up with more results. I used Hotbot and it came up with over 300 hits (although I'm not sure how useful most of these would be).

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Dolphin Sex - Received Jan. 8 from Adam

Q: I've heard how dolphins reproduce, but couldn't understand it well enough. Can you explain from step 1 on (mating rituals, dances, procedures, etc.)? Thank you for your help. Thank you.

A:Here's what I could find on dolphin mating habits. The readiness of females to mate is given to surrounding males by cues such as change of shape and colour of the genital area, body language, and possibly by hormones release in urine and feces. Courtship leading up to mating involves belly contact between the pair, sometimes upright, and sometimes lying horizontally. When horizontal, the male usually swims beneath the female. This courtship may be practised by animals of any age and sometimes by animals of the same sex, and at different times of the year. Courtship doesn't always lead to mating. Courtship rituals include chasing, simultaneous surfacing, breaching, and flipper contact, as well as vocalizations. When it comes time to mate, the pair hold onto each other with their flippers, the male's penis comes out of the genital opening, and internal fertilization takes place.

The gestation period for most toothed whales is between ten and twelve months.

When the calf is born, the mother takes it to the surface for its first breath. Then she, or another female, bites through the umbilical cord. Throughout the calf's youth, assisting females, or "aunts" will aid the mother and calf by providing extra protection and surveillance, as well as baby-sitting the calf while the mother goes off to feed. The calf relies on its mother for milk for 18-20 months, after which it can feed on solid food.

As the calf gets older, it socializes more with other animals and spends less time with its mother. Eventually, the calf will leave its mother and form a group with other individuals of similar age.

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 Dolphins and the Titanic - Received Mar. 7/00 from Darrell Nave in Tracy, California, USA

Q: In the movie TITANIC we are shown dolphins playing in the bow wave of the ship as it leaves Ireland in April. Is this realistic?

1) Dolphins in the north Atlantic?
2) In the month of April?
3) Of a type that would play in a bow wave?

Thank you in advance for your answers.

A: First, yes there are dolphins in the north Atlantic in April. The scene where the dolphins are riding the bow wave is a day or two into the trip which would put the Titanic southwest of the British Isles in the Gulf Stream. However, when they show the dolphins in the movie they switch between two species dolphins, the common dolphin (Delphinus delphis) and the bottlenose dolphin (Tursiops truncatus). Both of these species could be found in the north Atlantic Ocean in April and both species would ride the bow wave. So it would be correct information if they had not switched between the two species.

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Dolphins's Age - received June 28/00 from Chris in Holbrook, MA

Q: How old do dolphnis live to

A: Great Question!

It is quite difficult to measure the life-span of a dolphin in the wild because dolphins live for so long (possibly as long as the researcher who is trying to track it.)
One way to find out the age of a dolphin is to look at its teeth: As a dolphin grows, it lays down layers of dentine on the inside of each tooth. If you remove a tooth and cut through it, you will see these layers. The number of layers you count will indicate the age of the dolphin.
The oldest known dolphin in the wild was found to be 51 years old. Most dolphins, however, have a far shorter life-span. One study has estimated the life-span of the bottle-nosed Dolphin to be 25 years.

I got most of this info from a great book called "Dolphins of the World" by Ben Wilson, 1998.

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Dolphin bellybottons - received July 5/00 from Elizabeth in Franklinton, CA.

Q: Do Dolphins have bellybuttons? If so what are they there for?

A: Yes, dolphins have belly bottons.
Belly buttons are actually just a scar that remains from a baby's severed umbilical cord. The umbilical cord is vital to a developing baby (the fetus) within it's mother, because it connects the fetus to the placenta, an organ where materials are exchanged from the mother's blood to the fetus' blood. This is the only way that a developing fetus gets the nutrients that it needs, and gets rid of its waste. The materials are carried in the baby's blood that runs to and from the placenta, through the umbilical chord. The umbilical cord is therefore very important.

There are three types of mammals:

monotremes: egg-laying mammals
example: the platypus

marsupials: pouched mammals
example: kangaroo, opossum...

placentals: mammals that develop a placenta
(most familiar mammals in North America.. including whales and dolphins)

All placentals hve belly bottons.

Thanks for the great question!

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Are dolphins bald? - received August 1/00 from Jeffrey in Fallbrook, California.

Q: Are dolpins bald?

A: Yes, dolphins are bald!! Cetaceans (whales and dolphins) are unique among mammals because their dermis does NOT contain any hair follicles, sebaceous or sweat glands. Dolphins have thick layers of blubber for insulation instead of hairs. Their epidermis is 10-20 times thicker than human skin and is lined with hydrodynamic ridges. Its thickness helps to maintain the skins rigidity in the water and the ridges allow fast dynamic swimming. For information about the general biology of dolphins take a look at the dolphin section in the Answer Archive at http://oceanlink.info
or check out these sites:
Dolphin Biology Research Institute: http://www.mote.org/~rwells/
The Wild Dolphin Project http://dolphin.wwwa.com/
Thanks for the question!

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Dolphin Genders - received Sept. 1/00 from Julia in Iowa.

Q: How can you tell if a dolphin is a boy or a girl?

A: Great question!
For some dolphins it is easy to tell the difference between sexes, and for others it is more difficult. Killer wales are dolphins, and female killer whales are quite distinguished from males by the shape of their dorsal fins. Males have a long and straight dorsal fin, while females have a shorter and curved dorsal fin.

In most dolphins, the male grows to be longer and bulkier than the female. But this is not very helpful if you see one or two dophins in the wild and you don't know if they are the same age.
A reliable way to distinguish malee from female dolphins is to have a look at their lower belly. Males have two slits on their lower abdomen, one longer one called the genital slit, and one shorter one called the anal slit.
Females have one long slit which does the job of the genital slit and the anal slit. (the job is to contain the genitals and the anus, while the dolphin's body remains streamlined). The female has two small slit on either side of her long one, which contain her tits, from which her babies can suckle milk.

Their lower bellies look something like this:

It is not likely that you will be able to see these marks on a dolphin in the wild, but this is how the biologists that work with dolphins tell them apart.
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River dolphins - received from Michelle in Guyana, South America

Q: I am looking for information about river dolphins and whether they compete for the same fish resource as local fishermen?

A: As far as I can tell, the dolphin in your area is Inia geoffrensis (Boto, Amazon River, Pink Porpoise, or Pink dolphin. This species feeds on crustaceans, catfish and small freshwater fish. The ICUN lists this species as "vulnerable". There are many threats to this dolphin due to increased human development in its habitat. They become tangled in fishing nets, are hunted, affected by heavy metal pollution coming from gold mines, and damming for hydroelectric power often separates the dolphins from their food source. I am sorry that I couldn't find more specific details on the species of prey the Boto eats, or if their prey conflicts with commercially fished species. However, there are so many threats to this species, it would be easy to come up with many conservation based projects. The following websites may be useful as well: http://www.isptr-pard.org/dolphin.html and http://www.seaworld.org/endangered_species/boto.html

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Dolphin Pox - received on Dec. 10/00 from Deborah

Q: What is dolphin pox? Does it kill dolphins?

A: Dolphin pox is a skin disease of cetaceans. Both free-living and captive dolphins have been prone to show these skin lesions. The lesions are discrete, raised or smooth, round to irregularly round groups of pigmentation that form rings ranging from 1 to 5 cm in diameter. 

Electron microscopic studies of the lesions have revealed viral particles consistent with a poxvirus.  The development of these lesions is thought to be associated with stress, poor environmental quality, and poor general
health of affected dolphins. A study done by Baker, concluded that of the cetaceans surveyed in his study, 69% were infected by some kind of skin lesion. Some were caused by trauma and others were from a viral infection by the poxvirus.

However, from lectures I have attended by marine mammal pathologists in British Columbia, my understanding is that although skin lesions are almost always present in stranded cetaceans, they are rarely if ever the cause of death. Sometimes the opening of such a viral infection can reduce immune repsonse and contribute to further contractions of bacterial diseases.

I found this quote in one study: "It does not appear to be detrimental to cetaceans, and is generally a self limiting disease." and also. "Although this virus does not appear to cause serious illness in cetaceans, the development of these lesions usually occurs in periods of poor health and stress". So, the pox doesn't kill dolphins, it only can deteriorate their health enough to make them susceptible to other diseases.

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Dolphin Senses - Reseived from Bonnie Feb 6/01

Q: How do bottlenose dolphins excrete? Also, how would bottlenose dolphins react toward bright light chemicals and sharp objects?

A: Dolphins have very well developed sense. They have excellent eyesight - but this is only beneficial near the surface, where light still penetrates through the water. At greater depths, dolphins use echolocation (a series of clicks that rebound off of objects to inform the dolphin about the distance away and size of objects in their surroundings) to "see". Although it is not clear if dolphins can smell, they can taste, and can sense chemicals (they can use pheromones to communicate). They also have very sensitive skin, which also plays a role in communication, and they are able to feel pain. So, dolphins could sense and react to bright light, chemicals, and sharp objects - but I could not find anything specific enough to say how. It probably varies with the individual dolphin, but if the sharp object produced pain or if the chemical was unpleasant, they would probably move away from it.

Dolphins have genital and anal slits on their bellies. As mammals, they would excrete similar to the way other mammals do.

Check out this site for more great information about dolphins and other cetaceans!

http://www.cetacea.org/

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Captive dolphin release - received on Feb. 5/01 from Erin and Abby in Maryland

Q: If dolphins are kept in captivity, can they ever go back to their natural habitat? Are they excepted back into the pod?

A: This is a great question! There is much debate and controversy surrounding the release of captive dolphins and whales. Sometimes, the animals are only in captivity temporarily, for rehabilitation purposes, and then are released. However, it is much more difficult to release a dolphin that has been in captivity for many years, or that was born in captivity. Some concerns are that the dolphin won't know how to catch its own food, that it won't fit into the complex social structure of wild dolphins, that it will transfer new diseases to wild dolphins, that the captive dolphin will have a weakened immune system and more easily develop a disease...the list goes on and on. Many marine mammals have complex social structures. Killer whales, for example, have dialects that vary from pod to pod. Each pod consists of a family group, the head of which is the maternal female. It is difficult to return a captive Orca, especially if people do not know what pod they came from. One way aquarium staff may prepare a whale for a return to the wild is to play tape recordings of vocalizations from the whale's pod. There are many people who believe that all captive animals should be returned to the wild. I am sure you have heard the story of Keiko, the whale from the movie "Free Willy". A lot of money has been spent to prepare Keiko for a release into the wild, but it is unclear whether he will ever be ready. There are many websites dedicated to conservation groups who disagree with keeping dolphins in captivity, and who support the release of dolphins back into the wild.

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Dolphin strandings - received on Feb. 16/01 from Nicole in Illonois

Q: If there was a beached bottlenosed dolphin I would like to know how a person from a rescue team would save this dolphin.

A: Strandings occur more often in small toothed-whales and dolphins than they do for larger, baleen whales. Dolphins sometimes strand alone or in groups of 20-30. Usually, if a whale is found stranded it is because it had already died offshore. However, live strandings are believed to occur when dolphins and whales make a mistake in reading the Earth's geomagnetic field that they use for navigation purposes. The navigation error may occur a couple of days before the stranding, but the whale does not notice until it lands on the beach. There is little hope in saving large beached whales, because they are so heavy their weight crushes their internal organs once they are out of the water. However, rescue efforts can be made to return dolphins and smaller whales. Often, this is a difficult process due to the size and disorientation of the animal.

After finding a stranded whale, one should contact the coast guard or police. Standing well back, observe the whale to see if it is still alive (watch out for thrashing tails). If the whale is still alive, try to keep the delicate skin cool and damp using a towel or some seaweed. Take care not to cover the eyes or blowhole. Even if the animal is dead, record information such as size, species and location. One book recommends setting up different teams: to keep the animal wet and cool, to keep curious observors away, to organize food and warm clothing for volunteers, to prevent other strandings if there are more whales near shore etc. If other whales are offshore, make note of numbers, size and colour as well. An expert must be present to make the decision of whether the dolphin is in good enough condition to be returned to the water. Slings, tractors, or front-loaders can be used to transport the dolphin back to the water. Their skin is very delicate, so they cannot be dragged and should be handled gently. The animal will often be very dazed when it returns to the water and may need to be supported by volunteers until it is able to swim on its own.

Check out this webpage for further information. http://oceanlink.info/oceanmatters/strandings.html

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Sleeping dolphins - received on Feb. 22/01 from Michele in Utah

Q: Do dolphins sleep? If they do, then how?

A: Yes, dolphins do sleep! It is believed that they "shut off" half of their brain at a time while they are sleeping. The other half of the brain remains functioning to allow the dolphin to continue to function. After awhile, the two halves switch, and the other half of the brain gets a chance to rest!

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Cows and Dolphins

Q: What do Cows and Dolphins Have in Common

A: You would be very surprised to know just what cows and dolphins have in common. Well not so much with cows/dolphins but more in tune with overall whale/dolphin evolution.
Most scientists believe that whales/dolphins evolved from even toed ungulates (hoofed animals) which includes modern day cows and deer. these early animals were carnivorous much like todays wolves but their feet were like those of cows and horses. Just like todays carnivores these whale predecessors have several different kinds of teeth. overtime these hoofed ancestors of the whale adapted to their marine environment and eventually became the cetacean species that we know and love today.

In terms of direct comparisons between the cows and dolphins they are both mammals and vertebrates. Cows likely have more in common with baleen whales (in terms of cross species comparision) because baleen whales are the grazers of the ocean. Cows on other hand are the grazers on land. Dolphins are carnivores and usually eat other fish.

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Dolphin Age Distinctions

Q: What is a Dolphin called after a calf?

A: Most of the time a dolphin is called a sub-adult or a juvenile after it is no longer a calf. Some scientists may call a juvenile dolphin a teenager as a joke.


 KILLER WHALES

Killer Whale Markings - Received from Kevin in Ontario.

Q. Do the markings on killer whales specific to which pod they belong to?


Hi Kevin: The marine biologists studying killer whales in British Columbia have identified pods of whales through their vocalizations and dialects. The marks on dorsal fins and the shape of the saddle patch vary so that individual whales can be identified, but there is no link between the markings and dorsal fin within the pod. The dorsal fins of transient whales that range in the open ocean are more pointed than those of resident killer whales that are found in the waters around Vancouver Island and Puget Sound.

See you on the water sometime!

Answered by Margaret Butschler, Vancouver Aquarium.

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Whatever happened to A57? - Received from Bonnie on Vancouver Island.

Question: I would like to know the answer to A57's demise. The paper reported the death with autopsy to follow, I haven't heard anything since about cause of death. Seeing this is the second whale in 2 yrs. to have died near Powell River could there be a connection? Maybe too polluted with chemicals?

A. For those who may not know, A57 is the code number for a resident Killer Whale that lived in the waters around Vancouver Island. The whale was found in distress in late 1996, and died shortly after.

According to the people that examined A57, the whale died of a massive bacterial infection that was caused by an infected tooth. The bacteria that caused the infection is called Erysipelothrix, and it is known in fish, marine mammals, and some domestic farm animals.

It does not seem likely that marine pollution played any role in A57's demise. This was in all likelihood a completely natural event.

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Orca Questions - Received from Nicole in British Columbia.

Q: Since I absolutely love orcas, I would like to know:

1) What is the proper name Orca or Killer whale? Personally I like Orca, but is that right?

2) Generally how long do they live?

3) I live in B.C. Canada, is it a good job to get into, work wise? I mean are there jobs out there?

4) I've always wanted to touch an orca, what does it feel like? Is it rubbery like they say on "Free Willy"?

A:

1. Both names are essentially correct. The name "Killer Whale" is the common English name, while the scientific, or Latin name is "Orcinus orca" The first part of the Latin name is the genus, and the second part is the species. Many people prefer the name "orca" because it does not have the negative connotations that the term "killer" has.

2. For ages of killer whales, see our OceanLink pages on Killer Whales in B.C. and Killer Whales at the Vancouver Aquarium.

3. We live in B.C. Canada too - congratulations on choosing such a wonderful place to live! Please see our OceanLink pages on careers in marine biology for more information on job prospects. It is often difficult to find jobs working directly with marine mammals, but it can be done if you are very persistent! If you live in the Vancouver area, you might consider volunteer work at the Vancouver Aquarium.

4. Yes, touching an orca is quite the experience. I haven't seen the movie, but the description sounds pretty good. The skin is very very smooth to the touch, yet when you touch an orca, it feels quite firm. The very thick layer of blubber under the skin means that you can't feel any muscle tissue when you touch the animal.I'd have to say that it feels very nice!

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Orcas and pollution - Received from Rachel in Bellingham, WA.

Q: How is the Orca's environment being changed By pollution? Please be specific about different kinds of pollution. I am doing this for a science fair project. I would also like some info on how orcas communication.

A. It is difficult to say how environmental changes such as global warming or acid rain affect orcas and other cetaceans but water pollution and habitat damage have certainly shown to be problems for these animals. Killer whales, or orcas, are a top predator in the ocean. This means that they sit at the top of the food chain and have few, or no, predators. These animals also live for a long time. Both of these things make them susceptible to long-term accumulation of pollutants or toxins.

Killer whales are the last link in a long line of food consumption. For instance, a killer whale can eat 400-500 herring per day. Each herring might eat about 7000 copepods (a type of animal plankton) per day which in turn eat 130,000 pieces of phytoplankton (plant plankton) per day. If a toxin is absorbed by the phytoplankton then the toxin accumulates in each step in the food chain with the killer whales receiving the largest "dose". As I'm sure you know, killer whales also have a lot of fat, called blubber. Fat generally tends to accumulate toxins so this is another reason whales can be so susceptible to pollution in the food they eat.

Any problems that affect the food or habitat of killer whales can affect these animals. Disturbances when they are trying to rest, loss of food sources (the decline of salmon on the west coast may very well affect whales too), and habitat degradation, are all types of 'pollution' or environmental problems that can potentially harm killer whales.

Answered by Adrienne Mason

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Orca Rubbing Beach - Received Oct.17/99 from Amanda in Arizona

Q: Have you heard of "The Rubbing Beach". Whales (primarily orcas) go there and give birth and rub against the smooth peebles at the bottom. It is very popular place. Where is it located? (State, city, directions). Any other info you could give me would be great! Thanks!!

A: The rubbing beach that orcas visit that I am familiar with is in British Columbia in Canada. It is located in the Johnstone Strait (north eastern side of Vancouver Island near Telegraph Cove) in a a place called Robson Bight. Robson Bight is located along a typical route where resident killer whales forage and has several beaches that are frequently used by killer whales for rubbing. In the past, this site was frequently visited by whale watchers and there was a huge amount of boat traffic in the area. The orcas stopped coming to the area because of the excessive boat traffic. It was in 1982 that Robson Bight was made an Ecological Reserve by BC Parks as a sanctuary for killer whales and to protect these important rubbing beaches. People are no longer permitted in the area, but there are a lot of other whale watching opportunities all along the coast of British Columbia. I suggest you check out the OceanLink Eco-Adventure page and search the net for other whale watching companies which may be closer to you.

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Orca classification - Received Jul.13 from Michelle in Boston

Q: Why are orcas classified as dolphins ?

Killer whales (Orcinus orca) are in the taxonomic family Delphinidae, along with several other species of dolphin and porpoise. All of these animals are odontocetes, which means they are toothed, cetacean marine mammals.

Generally, the term whale is used to indicate size rather than zoological affinity. "Whale" simply refers to something that is rather large. Orcinus orca is more closely related to dolphins and porpoises than any of the other marine mammal families, and therefore it is considered a dolphin. However, because O.orca is the largest species in the dolphin family, these animals are sometimes referred to as whales. If you find this confusing, you are not alone, because the common nomenclature for these animals is not very consistent.

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Orca colouration - Received from Nicole in B.C.

Q Why do only some of the orcas have the white spot on their back behind the fin? Is it only some pods that have that? Does it mean anything?

A. Dr. John Ford from the Vancouver Aquarium writes:

"I do not know of any population without any saddle patch, although it is much reduced in some regions. Most researchers believe that the the white patches and grey saddle patch do serve as disruptive colouration to confuse prey or to help coordinate cooperative foraging behaviours by providing more concise visual markers."

Robin Baird and Pam Stacey analysed the pattern of pigmentation of the saddle patch in 372 resident sand 99 transient killer whales from B.C., Alaska, and Washington. They found that of the five different saddle patch types, all were observed on residents, but only two occurred on transients. In addition, saddle patch pigmentation patterns were similar among clans of whales within a community. They suggest that saddle patch shape may be inherited to a large degree, and may be used to delineate stock of killer whales from other areas.

For more information:

Baird, Robin and Pam Stacey 1988. Variation in saddle patch pigmentation in populations of killer whales (Orcinus orca) from British Columbia, Alaska and Washington State. Can J. Zool. 66:2582-2585.

Evans, W.E., A.V. Yablokov and A.E. Bowles, 1982. Geographic variation in the color pattern of killer whales (Orcinus orca). Rep. Int. Whaling Comm. 32: 687-694.

Thanks to Lara Gibson for assistance with this answer.

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Orca Nickname - Received Jan. 19/00 from Dalton Greiner in Pennsylvania

Q: Where did the Orca get its nickname (Killer whale)?

A: Orca whales have the nickname "killer whale" because they are actually kill other whales. There are three types of killer whales and they differ in their feeding and social behaviours. Transient killer whales, are the type of killer whales that kills other whales. They feed on marine mammals, such as seals, sea lions, whales, and dolphins. Resident killer whales feed on fish, such as salmon. The third type of killer whales is the offshore killer whales and these orcas feed on fish as well.

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Orca Lifespan - Received Jan. 16/00 from Chrissy Alvarez in San Antonio, Texas

Q: Do orcas live up to 25 yrs?

A: Female orcas will live to be 50 years old on average, but some are known to live to 65. A male orca will live to be 30 years old on average, but may live to be as old as 45.

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Offshore Killer Whales - Received Jan. 25/00 from Mona Wolfert in Port Moody, BC, Canada

Q: When was it first discovered that there is a third type of killer whale, the offshores? Who made that first discovery? Where were they first noted? Any other information you could give me would be much appreciated. I am co-hosting a Pro-D day workshop on February 18th on Whales & Dolphins in the classroom (across the curriculum) and would like to include this newest category of orca. Thanks so much for your help.

A: Offshore killer whales were discovered the early 1990s (1990 to 1992) by the the Pacific Northwest killer whale researchers consisting of John K. B. Ford, Graeme M. Ellis, and Kenneth C. Balcomb. The offshore killer whales first encounters took place near the Queen Charlotte Island (Haida Gwaii) and 15 or more kilometres off the west coast of Vancouver Island. Offshore killer whales tend to be found on large groups of 30 to 60 individuals and are rarely seen in protected coastal waters. Researchers believe that offshore killer whales spend most of their time on the continental shelf, feeding on schooling fish.

If you are interested in more information on killer whales, an excellent source of information is "Killer Whales" by John K.B. Ford, Graeme M. Ellis and Kenneth C. Balcomb.

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Killer whale skeleton - Received Sept. 18 from Nicole in Madison, NJ.

Q: How many bones is the skeletal system of a killer whale composed of?

A: Killer whales (Orcinus orca) generally have 50-52 vertebrae, 11-12 pairs of ribs and up to 21 phalanges in their first through fifth digits. Mammalian skulls are composed of approximately 30 bones which make up the cranium, face and lower jaw. For more specifics about whale anatomy, see the following reference: Tinker, S.W. 1988. Whales of the World. Bess Press, Honolulu, HI. 310 pp.

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Where to work with and learn more about Orcas? - Received from Joan in Seattle.

Q: I live near the Puget Sound and am interested in participating in research on orcas. Are there any opportunities for me and my children (ages 4 and 7)? If not, where would you suggest to go to learn more about whales and dolphins? We are homeschoolers, so even places with normal business hours are a possibility.

A.
In your area, the best place to start would be the Center for Whale Research, which is located in Friday Harbor, in the San Juan islands. They undertake research programs, and are always looking for new members as well as volunteers. Members receive current information about cetaceans, as well as current research projects. They also have an interesting publication out, geared for Orca lovers in the Puget Sound area: Orcas In Our Midst; the whales that share our inland waters.

Center For Whale Research
P.O. Box 1577
Friday Harbor, Washington
98250

The center may also have other ideas regarding places that you may go in the Seattle area to learn more about whales and dolphins.

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Why Killer Whale Fins Flop Over - Received Nov.17/99 from Sarah Fullbrook in Hope, BC

Q: You know how sometimes when orcas are in captivity their fin can flop over. Is this due to chlorine or chemicals in the tank?

A: Dorsal fins are supported by cartilage just like your nose. When a male resident killer whale goes through his "growth spurt" at around the early teenage years, the dorsal fin grows really tall, really fast.

Why is the fin bent? Well, as the fin gets tall it also gets heavy. A whale with a straight dorsal fin has spent lots of time in deep water, where the water pressure keeps the fin upright until the cartilage hardens.

Resident Killer Whales that went through their growth spurt in captivity have a bent fin because the pools aren't deep enough to create the water pressure needed to support the soft cartilage in the fin so the fin's own weight makes it flop over. Once the cartilage hardens, the fin is shaped forever.

Important Note: This phenomenon is not restricted to captive whales, it has been spotted in wild resident populations as well. The theory is that these whales were spending lots of time in shallow bays and shallow feeding grounds during their growth spurt.

Shallow water = low pressure.
low pressure + soft, heavy cartilage = bent dorsal fin

Answered by Todd Nivens from the Vancouver Aquarium

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Killer Whale Echolocation - Received Nov.21/99 from Elizabeth in Alberta, Canada

Q: What is the difference in echolocation between transient and resident killer whales? How do the whales use sound to feed? How do the whales hunt?

A: Resident killer whales travel in large, stable pods containing 10 to 20 whales and follow predictable migratory paths. Residents eat mainly fish, especially salmon. Foraging resident pods will spread out and form a broad front that sweeps along narrow passages, often from shore to shore. The pods move in a predictable fashion, from one good feeding place to the next. When foraging for food, resident killer whales exchange underwater vocalizations, pod members keep in contact and perhaps alert each other of the presence of prey. The whales will produce a series of rapid clicks that are used to echolocate the salmon and for navigation. Once the fish prey are found they are usually captured and eaten by the individuals of the pod. By remaining in stable pods for generations, resident killer whales can pass on their foraging knowledge and benefit from previous generations.

Transient killer whales feed on marine mammals, such as harbour seals, California sea lions, Stellar sea lions, harbour porpoises, and Dall's porpoises, just to name a few. Transient pods are not as stable as resident pods and usually the pods consist of a mother and two or three offspring, a group of unrelated females, but males usually forage alone or may team up for a short time to catch a prey item. Transient movement is unpredictable and they roam widely entering small coves, bays, and channels in search of food. They dive for as long as 5 to 15 minutes, where as resident killer whales only dive for 3 to 4 minutes. Transients always forage in silence, probably because their marine mammal prey would be able to detect their presence if they echolocated. Instead of echolocation, transients find their prey by "passive sonar", listening for the sounds their marine mammal prey are making. Vocalizations do occur when transients are killing and eating their prey. Transients usually cooperate with one another when they are hunting large prey, such as sea lions. The whales hit their prey with their flukes to stun them and then prey item usually drowns. Transient killer whales usually share their food.

Check out this website for more information on killer whale research around British Columbia: http://www.vanaqua.org/conserv/Cetacean/Field/field.htm

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Do Killer Whales Eat Humans - Received Dec.1/99 from Thomas Goodhand from South-East of England

Q: I have heard that Killer whales do not attack humans from a good source, if this is true why not. Because they eat large marine animals such as seals and their fellow dolphins so why not humans they have come into contact with?

A: The type of killer whale that feeds on marine mammals are transient killer whales and they are not known to attack humans. Perhaps one reason is that humans are not usually found in areas where they are hunting. Another likely reason is that humans are not a very good food source. Seals and dolphins have high levels of blubber in comparison to other body tissue and are therefore good source of energy. Humans do not have as much body fat and are not energetically worth eating, the amount of energy it takes to consume humans is not worth it in comparison to our nutritional value. This has also been shown with many great white shark attacks. Most great white sharks do actually consume humans, they are actually just "tasting" us, it just so happens that their delicate tasting is fatal to most humans.

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Captive Killer Whale Behaviours - Received Mar. 1/00 from Steve in Texas

Q: First I must say that I have got to be the biggest killer whale fan!
any ways, in the movie free willy when the boy (i think his name is Jesse) fell and hit his head on the side of his tank and fell in the water and almost drowned, would that really happen if a new trainer at sea world did the same thing would most likely that whale do the same thing since killer whales are supposed to be so friendly?

A: There have been incidences where trainers have fallen in the water and if there are people to help them out they are okay. However, one incidence happened up in Victoria, Canada, where a woman fell in a tank with killer whales when no one was around. They thought of her as a "toy" and they pushed her around in the water and she eventually drown, because no people were there to pull her out. The orcas did not intentionally want to hurt the woman, but they had learned that objects in their tank were supposed to be played with. This does not mean that the killer whales were not friendly, they do not understand that humans cannot play the same way they do and this type of "playing" can be deadly to humans. I do not know definitely that the killer whales at Sea World would not push an unconscious person to the edge if they fell in the tank. The whales would probably treat the person like they would during their shows. So if the whales were trained to push a person to the edge they would probably do that. Remember killer whales do not understand that we cannot breathe and swim easily in water, so they would probably not realize that a person needs to be pushed to the edge to breathe.

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Orca White Eye Patches - Received Mar. 9/00 from Heriot in Indonesia

Q: Why do killer whales have white spots by their eyes?

A: Killer whales actually do not have their eyes in the white patches, but their eyes are actually located under and in front of the white patch (see picture). The white patches on their head can be referred to as false eye patch. Both prey and predators usually attack the eyes of their enemies, because the eyes are one of the most vunerable places on an animal and if you can poke them the enemy will be blinded. By tricking their prey or predator into thinking their eyes are somewhere else, it will protect their eyes. So the trick worked on you, just like it does on other animals.

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How Orca Calves Are Born - Received Mar. 11/00 from Laura Evans in Alldavilla

Q: How do killer whales have babies?

A: Killer whales are mammals, just like humans and therefore they give birth to baby whales (calves) similar to humans. Female killer whales reach sexual maturity at 14 or 15 years of age. The gestation period is the time between the female's egg being fertilized by a male (mating) and the development of the young within the mother's uterus, just like human babies development in their mother's uterus. The gestation period is 16 to 17 months for a killer whale. If you look at the underside of a killer whale you will see a belly button because when killer whale calves are developing inside their mother's uterus they are attached to her by an umbilical cord, which provides them with all nutrients they need to develop. On the underside of both males and females you will also see a genital slit and below that the anus. A female killer whale will also two mammary slits on either side of the top part of her genital slit. The mammary slits are where the calves will feed by drinking their mother's milk from their mammary glands when they are developing. The genital slit of the female killer whale is where the calf comes out when it is ready to be born. When the female killer whale gives birth the calf leaves their mother's uterus through the genital slit and enters the world.

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Measuring Orca Populations - Received Mar. 22/00 from Thomas B Goodhand from the United Kingdom

Q: What methods do you use for studying the distribution and abundance of Orca populations.

A: Current research being done orcas in the coastal waters of British Columbia involve taking photographs of individuals for the past 30 years and identifying the individuals in pods by their dorsal fins, saddle patches and other markings, such as scars and dorsal fin shapes. Photographs are compiled from numerous different areas and are used to identify migration patterns of the pods and their members. Underwater acoustics are also used to identify specific pods. Resident killer whales, like humans, have dialects that are specific to their pod. Records of underwater acoustics are also used to identify pods of killer whales. More recently, genetic work is being done to determine how related different individuals are to one another. I suggest you check out the research of Dr. John Ford at http://vanaqua.org/conserv/Cetacean/cetacean.htm.

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Why Orcas Sing - Received Mar. 27/00 from Zussette Perez in Portland Oregon

Q: Why do orca's sing?

A: Orcas "sing" for many reasons. Killer whales produce different kinds of underwater acoustics (sounds) depending on the situation. One type is a series of rapid clicks used for echolocation to find food, such as salmon. Another type of underwater acoustic are sonar signals that are used for navigation and detecting the whales's surrounding environment. Killer whales use other kinds of sounds, mainly whistles and burst-pulse signals that resemble squeals, squawks, and screams, which are used to communicate with other individuals. In fact resident killer whale pods have dialects. They are actually the only other animal on earth, besides humans, that we know of, that have dialects. Every killer whale pod has their own dialect that is specific to their pod. Pretty amazing isn't it?

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A White Orca - received July 23/00 from Venessa in Idaho

Q: I've been studying orcas since I was 5. In the book I am reading it talks about "Chimo" a white Killer whale captured in 1970. Is there such thing as a white orca????

A: Chimo did exist, and was held at Sealand, a large public aquarium in Victoria, B.C. for two years. Chimo was an albino orca, meaning that she lacked pigmentation (colouration) in her eyes, skin, and hair. Albinism is a heritable condition (meaning it can "run in the family") that occurs in many animals, including humans. An albino animal is perfectly normal accept it has no pigments to give them the colour that you would expect. An albino human is usually quite blond and has pale skin.

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Pioneer killer whale research- received July 1/00 from Luke in the Philippines

Q: Please tell me about the pioneered names of researchers studying the killer whales. please email back as soon as possible, thank you for your kind consideration.

A: Here are a couple of influencial researchers of killer whales:

John Ford: PhD thesis in 1978 on orca sounds in Johnstone Straight. He had a revolutionary hypothesis that different pods of whales had individual dialects, and he basically figured out how they communicate, and haw they can learn sounds from each other. Dr. Ford is now the curator of marine mammals at the Vancouver Aquarium.

Micheal Bigg, Paul Spong, and others: 1970s - studied orca behaviour and how they are linked to the movements of salmon in the Pacific Northwest. They found that there were two distinct, independent groups (with different appearance, behaviour, vocal patterns, and feeding strategies) . The two groups are the residents and the transients. More recently, researchers have discovered a third group, the offshores.

Here's a site with more info about the development of whale research in the past 25 years:
http://www.vanaqua.org/conserv/Cetacean/Field/field.htm

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Orcas in California - received Aug 12/00

Q: Can you tell me the normal range for orca or killer whales to roam. In other words would it be possible to see a transient orca pod as far south as Monterey Bay or Morro Bay, CA?

A: Thanks for your question. Apparently orcas live in all waters of the world except for the high arctic. They are indeed sometimes spotted in and off shore of California. Transient orcas from BC and Washington have been identified as far north as alaska and as far south as Monteray Bay.

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French word for Orca - received Sept. 18/00 from Pamela

Q: What's Killer whale in french?

A: Great question! Luckily we had several french students and researchers here to help answer that question. There are two french terms for killer whale:
orque or épaulard
You can always use the scientific name too: Orcinus orca!

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Returning Orcas to the wild - received Aug. 28/00 from Hayley in Hong Kong

Q: Will all Orcas that have been in captivigy be put back in the wild?

A: It would be wonderful if all Orcas could be safely returned to the wild, but I don't really know if I can answer this. There are some problems with returning animals back into the wild once they have been kept in captivity. They may not know where to catch food, how they are supposed to get it, and even what they should be eating. They also may not have the survival skills for migration, or the social skills for interacting with mates or competing for mates. There is also a worry that Orcas that have been kept in captivity may carry diseases that could be very dangerous to natural populations.
Having said that, there are programs aimed at reintroducing captive animals back into the wild, but they are expensive and sometimes take many years.
Thanks for your question!

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Killer whale localities - received Aug. 27/00 from Justin in Melbourne, Australia

Q: Where are most Killer Whales found? e.g Which country?

A: Thanks for your interest in Killer Whales! Thier scientific name is Orcinus orca. They are second only to humans as the most widely distributed mammal, and they live all over the globe! However, the highest concentrations of killer whales are found in British Columbia, Washington and Alaska, the Antartic, Norway, Iceland, and Northern Japan. Because these whales move around alot and the ocean is a big place, we don't know exactly how many exist or where they all are.

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Orca Endangered? - received on Sept. 27/00 from Chrystina in Spearfish, SD

Q: Are Orca's an endangered species?

A: You have asked a very intriguing and contraversial question. Endangered species status and legislation is a hot topic for many environmentalists and biologists. Currently, killer whales are NOT listed as endangered. In the USA, they do not receive any designation on the Endangered Species Act, however are protected under the Marine Mammal Protection Act. This act was set up in 1972 to control the trade of marine mammal products and manage dwindling whale populations. Killer whales have never been a highly commercial species, although they are particularily popular aquarium whales and many were caught and held in captivity in the 1960's and 70's.
Canada does not have an Endangered Species Act yet however we are working on it. Canada does have an organization called COSEWIC (the Committee on the Status of Endangered Wildlife In Canada). And as of May 2000, their new list featured Northern Pacific resident Killer Whales in the "threatened" category and Northern Pacific transient Killer whales in the "species of special concern" category. The reasons for their addition to the list are:
1.Concern over dwindling salmon stocks in BC. Residents feed largely on salmon and as i'm sure you've heard on the news, the number of salmon has been reduced by overfishing, climate change etc.
2. PCBs: just recently a blubber sampling project of BC's killer whales was completed by Dr. Peter Ross. He found alarmingly high levels of PCB contaminants in killer whales. Especially transients. Because transcients feed at the very top of the food chain (ie: the feed exclusively on other marine mammals) they accumulate the most toxins
3. The numbers of killer whales in BC have been decreasing. Particularily in the Southern resident pods, which have been decreasing in number for the last 5 years. Recent death of male killer whale J18 was caused by a severe bacterial infection initiated by a external wound. It is not known if high levels of toxins worsened his infection.

So, my opinion is that although killer whale populations globally are fairly stable (and therefore do not warrant international "endangered" status), the BC populations do deserve close monitoring and concern. We must be particularily alert to further deaths in the diminishing pods of the Southern residents.

To keep up to date with endangered species and the killer whale situation in BC, check out these sites:
WhaleLink: http://www.whalelink.org/
COSEWIC: http://www.cosewic.gc.ca/

Update on this question: As of mid-October 2000, the United States, under the Endangered Species Act, has declared the North Pacific populations of killer whales (including those in BC and Washington) endangered!

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Killer whale reproduction - received on Feb. 16/01 from Dana in Virginia

Q: Do they mate with new males? How meny babys do they have in a lifetime?

A: Not a great deal is known about dolphin (orcas are the largest type of dolphin) reproduction. Partially because labour only takes about an hour to complete, so it is often not observed. The gestation period (the length of time the female is pregnant is about 15 months). Females give birth to one calf at a time, and rarely to twins. The calf remains dependent on the mother for suckling, protection, and development of social skills for several months to several years. In orcas, the calf suckles from 1-2 years. However, the mother will often reproduce or become pregnant again before the last offspring leaves.

Orcas are polygamous - which means that the males mate with more than one female. Females only have a short reproductive period every few years. As a result, calves are born only every 1.5-4 years. In orcas, the calving interval may range from 3-8 years. Female orcas become sexually mature ater 6-10 years, and males become sexually mature after 12-16 years. The bottlenose dolphin does not become sexually mature until 20 years of age! Due to this slow rate of reproduction, most dolphins have a fairly lengthy life span (female orcas may live to be as old as 70!). Larger dolphins only produce about 7 offspring in their lifetime.

I couldn't fins out any specific information about how many calves are born to one female in a lifetime, but judging from lifespan, sexually maturity, and calving intervals - I am guessing they have, on average, between 5-13 calves. The websites below may provide some more specific information.

Here are some great sites for more information about killer whales, Orcinus orca:

http://www.cetacea.org/orca.htm
http://www.enchantedlearning.com/subjects/whales/species/Orca.shtml
http://www.orca.online.fr/contents.htm#onto_repro

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Killer Whale Mating

Q: I am interested in how Killer Whales Mate and when the calfs leave their mothers in the wild?

A:Orcas have rarely if ever been observed mating in the wild. From what scientists do know Orcas mate belly to belly in the water. The male and female Orcas have their sexual organs located on their bellys (tucked away in a slit) about midway down there bodies. The sexual organs are tucked away a slit so the whales have less resistance while swimming.

Orca's calfs never fully leave their mothers in the wild! Orca societies are maternal (based around their mothers) and the calfs remain with their mothers even after they are mature. On average a female Orca matures at about 15 years and a male Orca matures at about 21 years and both of these are roughly accurate with human maturation. In the wild the female Orca's live to be about 80 years old while the males live to between 50-60 years.
Thanks for the great question.

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Killer Whales living in Fresh Water

Q: I was wondering why Killer Whales cannot live in freshwater?

A: Killer whales can survive in fresh water but the marine environment is a much better home for them. A salt-water environment is a much more stable than freshwater environments are. This is important because the saltwater stability makes it easier for a killer whale to live in saltwater. Also the marine environment provides a stable temperature environment unlike a freshwater one where there can be larger temperature variations. The saltwater environment also provides a lot more food than a freshwater one does. A lot of food is important for a killer whale because they have to eat enough to support a body weight from between 3000 to 12000 pounds! In other words they have to eat a lot to maintain body weight. Also the salt water environment is denser than freshwater and this allows for a greater ability to float in saltwater.
Thanks for a great question.

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Are Orca's Dolphins?

Q: I just bet a friend dinner that Orca's are Dolphins and wanted to know whether this is true or not.

A: The orca (Orcinus orca) is from the Family Delphinidae which includes all the dolphin and porpoise species. So yes the Orca is a dolphin. Usually it is referred to as a whale because of their large size.
Thanks for the question.

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 BELUGAS

Beluga Songs - Received Nov. 14

Q: Tell me about beluga whales' songs.

A: According to two U.S. biologists from their beluga studies in 1949, beluga sounds are "high-pitched resonant whistles and squeals, varied with ticking and clucking sounds - slightly reminiscent of a string orchestra tuning up - as well as mewling and occasional chirps. Sometimes, the calls would suggest a crowd of children shouting in the distance. At other times, there were sharp retorts, somewhat like a blow with a split bat or slap on the water."

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Endangered Belugas? - Received from Hillary in Dundas, Ontario.

Q. I am doing a project on beluga whales I would like to know how can we save them from extinction will there be any more left by the year 2020
AQUAFACTS BY VANCOUVER AQUARIUM

Q.Are belugas endangered?
A. Yes... and no... of eight Canadian beluga populations, three are endangered: southeast Baffin Island (Northwest Territories), Ungava Bay (Quebec) and the St. Lawrence River estuary (Quebec). Baffin and Ungava populations have about 1,000 individuals; the St. Lawrence population only 500. The St. Lawrence belugas are affected by industrial pollution which is concentrated in the fish they eat. For more information on the state of the beluga population in the St. Lawrence check out this site: http://www.medvet.umontreal.ca/services/beluga/index_an.html The Ungava Bay and the southeast Baffin Island populations are still recovering from commercial whaling.
- In some Arctic waters, belugas are potentially threatened by oil tanker and ice-breaker traffic, and by hydro-electric development.
- There are approximately 50,000 to 70,000 belugas worldwide - the beluga is the most abundant whale in Canadian waters!


As you can see, they are not currently in danger of extinction, but populations in some areas have low numbers. If we continue to look after them, and especially clean up their environment, there should be plenty of beluga whales around in the year 2020. Beluga whales used to be hunted in large numbers, but now, the only hunting that takes place is by Inuit hunters, and occurs only where the population numbers are very large (not in the populations that are in trouble).
As you can see in the above AquaFacts article, the main threat to the St. Lawrence Belugas is marine pollution. Who causes marine pollution? You do!!

You can help the Belugas most by making everyone aware that marine pollution harms many types of animals. Remember: everything that goes down your sink (or toilet - yuk!), or is put on your lawn, eventually makes its way to the sea. Many industries that make the things that you buy every day pollute the seas. If each of us does our part to stop pollution in our own back yards, this will help to clean up the seas.
Tell your friends and family - become an advocate for clean water!!
Learn as much as you can about Beluga Whales, and marine biology, and let people know what you've found out!!

Remember, even one person can make a difference!

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Green Beluga - received July 20/00 from Samantha in Connecticut

Q: Why dose the Beluga look green at night?

A: To answer your question, I'll need to explain a little bit about light.
Everything we see emits light, and that is why we see it. Light travels well through air, so we usually get to see things quite clearly.

Water is clear when you look through little bits of it, but when you look through lots it looks kind of green. This is because water absorbs some of the light that passes through it.

Light is made up of different colours, and some colours of light can pass through water better than others. Green and blue light can pass through water better than red and orange, so the things that you look at through large amounts of water tend to have a greenish tinge.

The white light coming off of a beluga and into your eye is composed of every colour, but the greens and blues are more likely to make it all the way to your eye than the reds and oranges. At night, the beluga isn't very well lit up, so all you see is the green light.

Light is very fascinating!

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What a Beluga Does in a Day - Received Nov.14/99

Q: Can you tell me about what a Beluga Whale would do in a day?

A: What a beluga does in a day, not only depends on where they live, but also what time of the year it is. One thing most belugas would do in a day is EAT! Belugas eat a wide variety of fish, shrimps and octopus. Belugas use sound to find their food! They emit clicks from their nasal passages. These clicks travel through water and bounce off objects like ice, food or the ocean floor. Belugas listen for the echoes of these clicks to determine where their food is located. That is another thing belugas would do in a day, sing. Well not sing songs like ones we would listen to, but belugas communicate with a wide range of sounds: clicks, chirps, grunts, squeals, screeches and whistles. Sound is an effective means of communication for belugas because it travels long distances through water. Belugas make such an array of sounds that nineteenth century sailors and explorers of the high Arctic named them "sea canaries". Belugas may also need to avoid predators. Killer whales in the Arctic eat belugas, so belugas will hide under ice patches avoid these hungry predators. In the summer and spring an activity that would be included in a beluga day would be mating and after 14 months a mother would give birth to a calf. These are just a few things that a beluga may do in a day, but there are still many things that we still do not know about belugas and there is definitely a lot more research that needs to be done. If you would like to know more about belugas I suggest you check out the OceanLink website under the AquaFacts section and check out the beluga whale page.

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Beluga Whales - Received from Jonathan in Washington.

Q: I am doing a school report on Beluga Whales. I would appreciate a bit of information to share with my 5th grade class. Here are a few questions: How did the Beluga get its name? Can you teach Belugas tricks? Do you have some Belugas in captivity, if so, what special types of care do you have to do for them? Thank you. I appreciate this.

A. The name "Beluga" comes from the Russian word for "white". This sure makes sense, since these arctic whales are all white in colour - in fact, their other name is "white whale".

The Vancouver Aquarium does not teach the marine mammals there to do "tricks". Instead, the focus of the programs at the aquarium is on public education. The animals are encouraged to perform natural activities, and the public is told why the animals do these activities, and what it means for them in their natural habitats. Belugas are very intelligent, however, and learn things very quickly.

There are five Belugas in captivity at Vancouver Aquarium. Their names are: Aurora, Qila, Allua, Kavna, Nanuq and Imaq. The water in the Arctic Exhibit is kept at a chilly zero degrees Celsius (32 degrees F), just like the water in the Arctic Ocean.

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Pollution and Beluga whales

Q: How has oil and other types of pollution affected Beluga whales?

A: Oil pollution will cause liver disease and reproductive problems in spome spcies of bony fishes. It is possible that this can affect Beluga whales as well. Oil pollution does have other effects on whales however. Oil will often kill many other organisms and this will affect the food chain. If the Beluga's food source is killed by oil pollution the Beluga will be in serious trouble. Most world oil pollution is from natural sources, routine machinery maintenance and from people pouring engine oil down the drain rather than dispose of it properly.

Other types of pollution that negatively affect Beluga whales are heavy metals poisoning and PCB's (Polychlorinated Biphenyls). Heavy metals can cause birth defects in whales and nervous system damage while PCB's can cause reproductive troubles in whales. The Beluga whales of the Saint Lawrence in Canada are dying from metals and PCB's more than from oil pollution.

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NARWALS

Narwhals - Received Aug. 25 by Anisa in Sydney, Australia.

Q: I am mentoring a year 5 child researching narwhals as her major project. She is writing it in a journal format, as a scientist studying narwhals, and so needs to ask someone who has been in the field, as she is to write about those experiences. If you can answer these questions, we are grateful.

While I have never personally been in the field studying narwhals, I'm more than happy to answer your questions as best I can.

1. What is the estimated population of narwhals and where are they located?
Narwhals (Monodon monoceros) have a discontinuous circumpolar range primarily above the Arctic Circle, and they are rarely found south of 70 N. Their population is estimated to be between 25,000 to 45,000 individuals.

2. Has global warming affected their migration patterns, and if so, how?
Narwhals migrate northward in the spring and southward in the fall, travelling in groups of up to 2,000 individuals. I'm unaware of any recent studies pointing to a change in migratory patterns in relation to global warming, although I imagine that if there were changes in ocean temperatures which affected the range of species narwhals prey on, the whales might be required to alter their migration accordingly.

3. Are narwhals known to be friendly towards humans?
The narwhal's predators include killer whales, walruses, sharks and polar bears. However, its main predators are humans. Narwhals are hunted primarily by Inuits both in Canada and Greenland for their tusk, skin, meat and blubber. I would imagine that narwhals are therefore rather wary of humans and might not approach them freely.

4. Is it suitable to dive with them for documentary purposes, and when is the best time of year?
Marine scientists and photographers have SCUBA dived with narwhals and documented their behaviour. The best time of year to observe narwhals in this manner would likely be in the summer, when weather conditions are favourable.

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Narwhal Info - Received Jun.29 from Isabella in Sydney, Australia

Q: Can't find anything on narwhal. Thank you. (her Dad typed this for her, she is 4)

A. The Narwhal (Monodon monoceros) is closely related to the beluga whale, and both are in the family of whales known as the Monodontidae. These gregarious whales are common in subarctic and arctic waters, where they feed on a variety of fish species, squid and shrimp.

The Narwhal is usually greyish-white in colour, with dark mottling of the back and sides. These whales lack a dorsal fin, which is replaced by a distinct hump. The animals have a bulbous forehead, a slight beak, and short, upcurled flippers. The Narwhal has an unusually shaped fluke with convex trailing edges. The male has a long spiralling tusk (like the fabled unicorn) which is actually a modified tooth, and is used like the antlers of deer in fights over females and a visual display of strength. Female Narwhals do not have tusks, and can be almost completely white in colour. For this reason, female Narwhals are often mistaken as Belugas.

During feeding, the whales spend little time at the surface, usually diving for periods up to 20 minutes. Members of a group may surface and dive at the same time. These whales have been seen spyhopping, lobtailing and flipper-slapping, but rarely breaching. The Narwhal blow is fairly weak and inconspicuous.

Predators of Narwhals include killer whales, walruses, polar bears and sharks. However, these whales have also been traditionally hunted by the Inuit for its valuable tusk and its thick skin.

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Narwhal's horn - received July 5/00 from Branden in New York

Q: What is a narwhal's horn made out of?

A: The horn of a male narwhal is actually one of it's two teeth. The left tooth usually grows into the long twisted tusk, while the right tooth remains within the gums. Female narwhals have two teeth as well, but they don't grow out past the gums. Some male narwhals hae been found with two tusks, in the case of both their teeth growing out.

I found this info in Eyewitness Books: Whale, by Vassili Papastavrou.

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Narwhal relationships - received Oct. 4/00 from Karolina in Sweden

Q: I wonder if you know: How is the relationships between the whales in a narwhal stock?

A: That is great question! Narwhal's (Monodon monoceros) travel in groups of 3 or 4 or up to 10 whales. During the breeding season they have been observed in large groups of up to 20 or 50 males showing "fencing" exercises. Fencing is a sexual display put on by males to compete for females. The size of tusks (often used in violent battles) will define the hierarchical status of males in a group. During migrations groups are often segregated by sex and age. the following groups have been observed travelling together:
1.immature males
2.mature females and calves
3.large adult females

These groups will generally hunt and feed together, often diving and surfacing at the same time.
Here are some websites with info on narwhals:
http://www.EnchantedLearning.com/subjects/whales/species/Narwhal.shtml
http://tqjunior.thinkquest.org/3500/Narwhal.html

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Narwhal Tusks

Q: If only male Narwhals have tusks how do females break through the ice to breathe?

A: Narwhals do not appear to use their tusks for breaking the ice. Biologists believe that the male Narwhal uses the tusk for fighting with other males for mating rights with females. Narwhals with larger tusks may have a better chance at mating with a female. For the most part Narwhals keep breathing holes open by simply using them a lot and preventing them from freezing up.

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 TOOTHED WHALES

Baird's beaked whale - Received Sept. 2 from Stephanie on Parris Island.

Q: Can you tell me anything about the bairds beaked whale? We are studing this in my fourth grade class.

A: Beaked whales are classified in the Family Ziphiidae, and are the least known of all cetaceans (whales, dolphins and porpoises). Some species of beaked whales have never been seen alive and are known only from dead specimens which have washed ashore. One of the reasons that Ziphiids are so elusive is that they live far from shore in very deep water. The most distinguishing characteristic of beaked whales is the presence of tusk-like teeth on the lower jaw of male animals (often females do not have teeth). There are 20 known species of beaked whales, although it is possible that there are others yet to be discovered.

Baird's beaked whale (Berardius bairdii) is thought to be the largest of all beaked whales, with adults measuring between 11-13 m (35-42 ft) in length and newborns estimated at 4.5 m (15 ft) in length. Both male and female B. bairdii have two pairs of teeth, with the front pair protruding out of the dolphin-like beak. Baird's beaked whales have a prominent bulbous forehead, small dorsal fin, small and rounded flippers, and a long, spindle-shaped body. Adults are usually greyish in colouration and males often display heavy scarring on their dorsal surface (upper side), likely due to fights with other males.

B. bairdii is found in deep temperate and subarctic waters in the north Pacific Ocean. When observed on the surface, they are found in a tightly organized group of 10-30 animals. They are usually visible for less than 5 minutes, after which they dive for approximately 25-35 minutes. These whales are known to congregate in offshore waters at least 1000 m (3300 ft) deep, and they rarely enter shallower waters.

For more information on these cetaceans see the Discover Beaked Whales page.

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Sperm Whales - Receiver Dec.5/99 from Emma in New Jersey

Q: Where did Sperm Whales get their name? What do Sperm Whales eat? and where do they live? Do Sperm whales Migrate?

A: The adjectival noun Sperm in the common name that refers to the spermaceti or sperm oil obtained from the animal's head, although some have suggested that it may refer to the large size of the male's retractable penis (approximately 2m). The latin name for of the Sperm whale in the Northwest Pacific is Physeter macrocephalus. Physeter is a Greek word meaning "blower," and refers to the whale's behaviour of making a vapor spout when it exhales air from its lungs at the surface. "Macro" means large and "cepahlus" means head, therefore "macrocephalus" means large head.

Sperm whales feed mainly on squid but also eat octopus and a variety fish such as salmon, rockfish and skates, some which are found at depths as great as 1,500 feet to perhaps 2 miles. The average male will consume up to 3.5 percent of it's body weight in squid. Sperm whales are found throughout the deep waters of the world's oceans, from the equator to the polar seas. Sperm whales do migrate from their breeding grounds and feeding grounds. To find out more information on sperm whales I suggest you check out this website and search for information on sperm whales, I am sure you will find more information there!

http://animaldiversity.ummz.umich.edu/

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Ambergris in Sperm Whales - Feb. 1/00 from Raul M. Orozco in Ontario, California, United States

Q: I know that ambergris is produced in the Sperm Whale's intestines. However I would like to know how it is extracted? Or does the whale dispose of it by vomiting or by a bowel movement?

A: Yes, ambergris is produced in the large intestine of only sperm whales, but only occurs in 1-5% of the animals and how it is formed is unknown. Ambergris is round-shaped, usually weighs between 0.1-10.0 kg, but some have weighed as much as several hundred kilograms! It is mainly composed of an ester of ambreine (a non-volatile, high molecular weight alcohol) and usually contains chitinous cephalopod beaks. Finally, to answer your question ambergris is passed through with the feces and also extracted in autopsies of dead sperm whales.

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Giant squid vs. sperm whale - Received Nov. 9 from Mrs. Dello Russo's class in Cambridge, MA

Q: In a battle between a giant squid and a sperm whale, who wins and why? How can scientists tell is the scars on a sperm whale's body are from fights with a giant squid on the bottom of the ocean?

A: In battles between sperm whales and giant squid, it's hard to tell who wins all the time. Considering giant squids have been found in the stomachs of sperm whales, and that sucker scars are often found on these whales, chances are the whales win a lot of the time. However, if a giant squid won, we'd really have no way of knowing because the whale's body would sink to the bottom of the sea.

Scientists can tell if the scars on sperm whales are from giant squid by comparing them to the suckers found in the stomachs of whales, and from squid washed up on beaches. The scars would tend to be pretty near circular and have serrated cut from the teeth in the suckers.

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Whale or dolphin? - received Aug 20/00 from Kevin in Washington.

Q: Is a Killer Whale related to a dolphin or is it really classified as a whale?

A: Killer whales (and five other small toothed whales, known as "blackfish") are classified in the family delphinidae, which also includes 26 species of dolphins. The blackfish are generally considered more related to dolphins than to other whale species, even know they are quite unlike dolphins in appearance.

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Blackfish

Q: While fishing yesterday I saw a large jet black animal in the ocean with a curved dorsal fin. The locals called it a blackfish but I could not find any information on this generic name. Any idea what I saw?

A: Blackfish is the generic name to describe a group of smaller toothed whales. These whales include species such as the Killer whales, the false killer whales, the pilot whales, melon headed whales and so forth. These whales are from the family Delphinidae that includes all of the oceanic dolphins.

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