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ASK A SCIENTIST: ANSWERS TO QUESTIONS Odontoceti Index to Questions DOLPHINS KILLER WHALES BELUGAS
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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.  BACK
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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.BACK TO ODONTOCETI INDEX OR ANSWER FILE
Q. When is a good time
to see a Dolphin being born? BACK
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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. BACK
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Q: Are Dolphin Tails real tails (vertabrae (sp?) column) where are the legs? Do some marine mammals have the legs adapted/evovled into tails ?
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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. BACK
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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.) BACK
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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. BACK
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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. BACK
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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. BACK
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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.
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.
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 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). BACK
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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. BACK
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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? 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.
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.)
Q: Do Dolphins have bellybuttons? If so what are they there for? A: Yes, dolphins have belly
bottons.
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. Check out these sites: BACK
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Q: How can you tell if a dolphin is a boy or a girl? A: Great question! 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.
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: International Society for the Preservation of the Tropical Rainforest
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.
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.
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.
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. Check out this webpage for further information. OceanLink's Ocean Matters, Strandings page BACK
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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!
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.
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
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.
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!
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.
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.
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.
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.
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.
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.
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.
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.
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. Answered by Todd Nivens from the Vancouver Aquarium
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
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.
Q: First I must say that
I have got to be the biggest killer whale fan! 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.
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.
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.
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.
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?
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.
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: 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.
Q: What's Killer whale in
french?
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.
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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A:
Yes, dolphin tails are true tails extending from the vertebrae
column.
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: