Talk:Great white shark/Archive 1
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Archive 1 | Archive 2 |
Hoax
Hmm. we but a hoax for a bit? A claim that a 12-year-boy named "Michael Brody" had been attacked and killed by one of the great whites off of Chatham, MA? The name "Brody" was a tip-off, but I think the story may already be making the rounds of the Internet.Lolliapaulina51 (talk) 23:22, 6 September 2009 (UTC)
Expert Please Address
This is concerning the following paragraph in the "Shark Attacks" section: , in any case, are not appropriate prey for white sharks as the sharks' digestion is too slow to cope with the human body's high ratio of bone to muscle and fat. Accordingly, in most recorded attacks, great whites have broken off contact after the first bite. Fatalities are usually caused by loss of blood from the initial limb injury rather than from critical organ loss or from whole consumption."
This seems to suggest great white sharks stop eating humans because the taste (or consistency) of humans tells them that they will have trouble digesting the prey. Armed with this knowledge, the shark then breaks off the attack.
Even though it's not out of the question, this seems fairly incredible to me. If it is true, an expert should explicitly state the mechanism that allows the shark to make such a judgment. --BishopOcelot (talk) 21:55, 18 April 2009 (UTC)
Unique or not?
Under the section on the shark attacks, there is a photo of a great white extending its head above the water. The following caption is attached: The great white shark is unique in the fact it is one of the few sharks that can spyhop above water. This makes no sense. Unique means that it is the only shark species to spyhop, the next part of the sentence implies there are others. Being no specialist on sharks, I don't know which of the two is right, but the caption certainly isn't. It'd be great if someone with more expertise would look at it.Hinakana (talk) 23:07, 24 December 2007 (UTC)
Endangered status
I'm not sure where the latest data can be found but I though http://www.redlist.org/search/details.php?species=3855 was the current and official status and if I can read that the status is vunerable but under consideration for endangered so I change back to vunerable, if that is wrong please inform where the latest data can be found and/or how often and old the web site is Stefan 13:40, Oct 13, 2004 (UTC)
- According to an article that was posted on the Internet only yesterday (10/12/04), the Great White Shark has been added to the endangered species list.
- Yes it has been moved to Appendix II after the CITES meeting this week - see also e.g. http://news.bbc.co.uk/2/hi/science/nature/3736042.stm.
- However a CITES Appendix II listing is not the same as a IUCN Red List grading of endangered. For instance the Basking Shark has been Appendix II for some time, but listed only as vulnerable. Then you get oddball situations like the Minke Whale being Appendix I yet Red Listed only as Lower Risk.
- It would not be at all surprising if IUCN changed the species to Endangered the next time the shark specialist group reports, however until then we should not jump the gun and continue to use the red list listing as we do for all other species. Hope that's helpful, Pcb21| Pete 21:06, 13 Oct 2004 (UTC).
- OK thanks, that clears things up. Stefan 07:38, Oct 14, 2004 (UTC)
Photo?
Some species of shark (primarily the carcharhinid sharks) have a thin membrane which covers the eye and protects it from damage during feeding and confrontation, it is called a nictitating membrane. Great White sharks do not belong to this particular family of sharks, and does not have a protective membrane available to keep it's eyes safe. Instead, right before an attack, the white shark will roll its eyes back in their sockets, protecting the lens and cornea from damage and at the same time, displaying the white of the sclera, which makes up the outer layer of the sharks eyes. AWH
Is the photo used photoshoped? I thought great whites closed their eyes as they bite. A white lid comes up from the bottom to protect them. It looks very strange to me.
Sorry but i just want to correct you, great whites do NOT have eyelids, they roll their eyes back into the skull and it looks as if their eye's have gone white. I think all mackeral sharks are the same. Necropolis123 16:56, 29 October 2006 (UTC)
Excerpt from this website: http://www.sharkattacks.com/satvermyth.htm "Some species possess a third eyelid which closes at the moment of the attack." Th e map is wrong you should get it up to standards, because new discoveries have proved that the White shark is all over the world.
- Footnote July 15th 2009**
I'm convinced the picture of a Great White breaching to catch a seal is actually one of an Orca. —Preceding unsigned comment added by 78.151.203.128 (talk) 06:01, 15 July 2009 (UTC)
- The animal certainly looks more like a great white shark than an orca. mgiganteus1 (talk) 07:18, 15 July 2009 (UTC)
- It is certainly a great white shark. The large white spots on an orca's head would be rather hard to miss. -- Yzx (talk) 07:45, 15 July 2009 (UTC)
Warm-blooded?
I had heard somewhere that great whites are warm-blooded. Can anyone confirm or deny this? Jeshii 13:53, Oct 17, 2004 (UTC)
- Not sure about the white, but some sharks like the shortfin maco has a warmer than the seawater temperature, not by much but by a few degrees. This I think can make them faster and therefore better at chasing fish. Since I'm not sure sure I did a quick google check, see the links
- * http://www.elasmo-research.org/education/topics/p_warm_bodied.htm
- * http://www.aquarticles.com/articles/breeding/McFarlane_Warm_Blooded_Fish.html
- * http://geopubs.wr.usgs.gov/circular/c1198/chapters/177-184_WhiteSharks.pdf
- So I would say that these few links are inconclusive, one say white shark is warm blooded, one that only mackrel sharks is and one that the short fin maco is, but not the long fin (both mackrel). Since great white is a mackrel shark I would guess that it is warmblooded but I need to check some books at home. Stefan 09:14, Oct 18, 2004 (UTC)
- It is indeed 'warmblooded', that means that its body temperature is slightly higher than the water. It has bloodvessels that passes through the swimming mussles to warm the blood. Same for some other sharks and tuna. Stefan 23:43, Oct 18, 2004 (UTC)
- The main fish article has a mention of the Great White being the only warm-blooded fish, so once y'all find out what's actually true please alter both this article and that (if necessary). Thanks! Ziggurat 00:24, Dec 17, 2004 (UTC)
- Most of the species in the family Lamnidae are homeothermic, capable of maintaining a body temperature slightly higher than their surroundings (World of Animals: Fishes, 1986).
- The main fish article has a mention of the Great White being the only warm-blooded fish, so once y'all find out what's actually true please alter both this article and that (if necessary). Thanks! Ziggurat 00:24, Dec 17, 2004 (UTC)
- It is indeed 'warmblooded', that means that its body temperature is slightly higher than the water. It has bloodvessels that passes through the swimming mussles to warm the blood. Same for some other sharks and tuna. Stefan 23:43, Oct 18, 2004 (UTC)
if you think about it they should be because they are mammals and they give birth to live young but im only in the 8th grade so what do i know lord_voldemort8675309@yahoo.com
I could be wrong but i don't think that great whites or other Mackeral sharks are warm blooded, there body temp is always a few degrees above water temperature but this can change with the temperature of the water...i thought that for an animal to be classed as warm blooded there body temp had to remain at the same all the time....?? can anyone confirm this or deny this...??Necropolis123 16:42, 29 October 2006 (UTC)
And also lord_voldemort8675309@yahoo.com sharks are NOT mammals.....they have gills and are fish.
The main reason great whites aren't mammals is that they don't make milk. Shark cheese, anybody? Notreallydavid 15:53, 26 November 2006 (UTC) (I don't make milk either, but some members of my family have been known to.)
OK I'm confused. In the Diet part, it says they're warm blooded, in the reproduction part they are cold blooded?Hqduong 09:02, 11 December 2006 (UTC)
Well, the problem is that "warm blooded" and "cold blooded" don't describe the range of possible temperature regulation systems in nature. Most mammals and birds are homeothermic (constant body temperature) endotherms (internally controlled temperature); hummingbirds, since they can go into torpor, are poikilothermic (variable body temperature) endotherms; amphibians and most reptiles are poikilothermic ectotherms (body temperature externally regulated; i.e. by the environment). Ectotherm/endotherm is close to what most people mean by "cold/warm blooded." GW Sharks are poikilothermic endotherms (their temperature is about 6-7 degrees above water temperature, so it is not constant but internally generated).
- I wonder whether the person who wrote the above excellent explanation could perhaps add some of the more technical aspects to the article and/or provide links to any other article on this topic GrahamBould 09:37, 7 January 2007 (UTC)
- That was me (I wasn't logged in.) I will do so. Vultur 23:58, 9 February 2007 (UTC)
Sharks are definitely not mammals that's for sure. Strangely they do have a lot in common with reptiles as do most fish. They'll often swim up to the surface for sunlight warming them the same way as say a lizard. This heat in converted into energy. Sharks are prolific around teh equator for this very reason. (Harry M Colley 02:37, 4 April 2007 (UTC))
The terms warm blooded and cold blooded are a bit out of date in the scientific community, with terms such as endothermic and exothermic being used instead. The White Shark has regional endothermy as it does maintain a constant temperature in certain parts of its body like the stomach and brain. It has the high haemoglobin levels and large heart that accompany the higher metabolic rate of typical endotherms. Non-essential parts are not kept at a constant temperature. See http://web.ncf.ca/bz050/wsphysio.html 81.153.85.7 17:44, 30 July 2007 (UTC)
I note that the automatic unit conversion of 14 degrees centigrade to 57 degrees Fahrenheit is incorrect. True, 14 degrees C is 57 degrees F, but a change of 14 degrees C is not a 57 degrees F change, but a delta of only 25 degrees. I don't know if the convert functions can handle deltas (where is it documented?) so I'm changing this to a manual conversion. RandyKaelber (talk) 20:01, 12 March 2009 (UTC)
Out of Place?
"Great Whites, like many other sharks, have rows of teeth behind the main ones, allowing any that break off to be replaced rapidly. Their teeth are unattached to the jaw and are retractable, like a cat's claws, moving into place when the jaw is opened. This arrangement also seems to give their teeth high tactile sensitivity." This seems like it should be in the first part, not the Attacks on Humans part. Agree, disagree? --OGoncho 20:56, 23 Oct 2004 (UTC)
- Agree, and should be in the shark article instead of here. not sure if all sharks have this though (whale shark?, basking?, cookie cutter?) but most have it. Stefan 12:32, Oct 25, 2004 (UTC)
- All of this is fine except for the part regarding "retractable teeth, like a cat's claws". Cats have evloved reatractable claws in order to keep them from being damaged and to ensure that they will be in good condition for when they are needed. What would be the evolutionary benefit a shark which can reatract it's teeth? A shark is built to lose teeth, and for others to take their place. No shark has teeth which can retract like a cat's claws. Period. AWH.
- Hmm... I removed the part about retractable teeth a few days ago, since I was unable to find corroboration for it (See my comment below). Anyone have a citation for retractable teeth? --TeaDrinker 00:34, 27 June 2007 (UTC)
- I thought it was the shark's jaw that protracts when biting, rather than the teeth retracting when not biting. I believe the purpose is to increase the volume of the mouth, thus there is a pressure difference between the sea and the inside of the mouth, sucking the prey towards the shark.80.7.122.153 (talk) 12:27, 31 May 2008 (UTC)a
- All of this is fine except for the part regarding "retractable teeth, like a cat's claws". Cats have evloved reatractable claws in order to keep them from being damaged and to ensure that they will be in good condition for when they are needed. What would be the evolutionary benefit a shark which can reatract it's teeth? A shark is built to lose teeth, and for others to take their place. No shark has teeth which can retract like a cat's claws. Period. AWH.
Size & longevity
Unserious estimate
It is not serious to estimate a predicted guess on four digits precission! In this case it is 2240kg, which means more than 2235kg and less than 2245kg and 4938lbs means not one lb more or less. Maybe the numbers 2300kg (5000lbs) are more useful for the intended purpose to suggest a rough upper limit. An articel, which is blocked against improvements should not need improvements. And a person, who has the power to block an articel should be expert enough to find such silly formal mistakes in the usage of numbers. It does not need a shark expert. CBa--80.137.123.224 (talk) 10:36, 18 January 2010 (UTC)
Candidates for largest recorded individuals
While searching for the largest measured – not estimated – Great White individuals, I've come to the conclusion that the "typical maximum" size is 6.0–8.0 m (16½–17¾ ft.) and 1,200–2,300 kg (2,700–5,000 lb.). Any bigger than this is truly spectacular. I've never seen convincing reports of individuals exceeding 6 m (20 ft.) length or 2,000 kg (4,409 lb.) weight.
Heaviest specimen
Commercial fisherman Joe Friscia captured an adult female Great White Shark in his drift gill net on September 18, 1985, about 24 km (15 mi.) southwest of Point Vicente, Los Angeles County, California. The shark was 5.36 m (17 ft. 7 in.) in length and weighed 1,878 kg (4,140 lb.). The shark's stomach contained the remnants of an adult Harbor Seal (Phoca vitulina) and a juvenile Northern Elephant Seal (Mirounga angustirostris). The accuracy of the shark's weight is indisputable, further detail can be found here – scroll down to the 5th photo.
On the Elasmobranch Research around Monterey Bay website list of large individuals, the heaviest specimen that appears to have been measured, rather than estimated, is a 2,120 kg (4,674 lb.), 5.57 m (18 ft. 3¼ in.) long shark caught off S.E. Taiwan on January 2, 2004. Caution advised here, however. Other references of the same author (Victor Lin) include some doubtful cases on the site, including even larger Great Whites, and a 1,176 kg (2,593 lb.) Tiger Shark (Galeocerdo cuvier). Yet it should be noted that this shark had the largest vertebrae measurements mentioned on this list.
The weight of the white shark caught off S.E.Taiwan in 2004 is authentic, as it had been weighed by the truck scale. The length, however, maybe a little bit doubtful. I have never met the guy who measured this shark to prove this measurement, and there were other lengths quoted by local media, despite not very precisely: (1)6~7 meters(China Times)(2)over 7 meters(Liberty Times). Photograph evidence suggests this to be a very bulky shark, conforms with the descriptions of witnesses "we thought it was pregnant because of the big belly." Also, the fins of this shark weighed 79 kg when fresh, suggesting a total weight of 1700~1800kg if it was in normal condition. (average 4.6 %)
The Heaviest white shark in my opinion, however, is not this specimen. A pregnant white shark caught off Kenya in 1996 was cut into chunks and weighed 2220kg, and this value did not include the body liquid and 14 embryos weighing 18~20kg. The shark would have been over 2600kg. Another 5.3m female white shark caught off Brasil in 1992 was extremely bulky too. It had not been weighed intact but the liver alone weighed 635kg by a scientific insitute. Considering the liver weight is about 20~25% of body weight, this shark would have surely surpassed 2600kg too. Another contender which may or may not been actually weighed was a 5.35m white shark caught off Sicily in 1987. It has been quoted weighing 2000kg, yet another source(Records of the Great White Shark in the Mediterranean Sea by Alessandrop De Maddalena)saying this shark weighed 2200~2500kg.VicLin (talk) 18:43, 21 September 2009 (UTC)
Longest specimen
A shark 5.94 m (19 ft. 6 in.) long, weighing 1,470 kg (3,241 lb.), was caught in Ledge Point, Western Australia, on March 22, 1984. This individual seems to have been accepted by the scientific community. Yet, at least on one discussion board, I've seen doubts voiced on this individual. A photograph of this shark suggests a robust individual, but since a shark this long would weigh 1,500–2,500 kg (3,300–5,500 lb.) with typical proportions, the given figures would put it very much on the slender side.
I can't promise that I've got all the facts right, the information I've found has been a bit sketchy. I wasn't able to find a good reference or a picture for this individual at the moment. I'll add the links here if I manage to find them in the future...
Another long individual was caught in Gansbaai, South Africa, on January 17, 1987. Its length has been reported between 5.67 m (18 ft. 7¼ in.) and 6.00 (19 ft. 8 in.), so it was probably never accurately measured. It weighed 1,214 kg (2,676 lb.) or 1,241 kg (2,736 lb.) – I don't know which one's the typo – after its liver (20–25 % of body weight) was extracted, so originally it must have weighed c. 1,600 kg (3,500 lb.).
If neither of these is accepted, I've seen a length of 5.54 m (18 ft. 2 in.) in a scientific sample, so the Great White must grow at least this long. Anshelm '77
- Update: Check out this page I've found. There's a pretty good case of a 7.23 m (25 ft) Great White, caught in Sète, France on Oct. 13, 1956. This is the longest Great White, that I know of, that (at least seemingly) has been accurately measured. I'm not totally convinced about the Ledge Point shark I mentioned earlier, and even less about the 6.1 m Prince Edward Island specimen – note that 6.1 m with given accuracy is exactly 20 feet, and besides Wikipedia I've seen only one other mention of this individual.
- "The model of a white shark preserved in the Museum of Zoology in Lausanne, Switzerland, is a mould reconstructed via casts from the original body of the specimen caught in Sète, France, on 13th October 1956: this is the largest white shark specimen whose complete morphometrics (made following Compagno, 1984) are available worldwide (De Maddalena et al., 2002). Considering that the size of this specimen is very close to 6 meters (583 cm TOT, 565 cm TLn and 458 PRC)."
- Further update: Based on the information above, I've also found this – what I find interesting is that they've come up with a much larger estimate for the 7.13 m (23 ft 4½ in) Maltese claim than the 5.2–5.5 m (17–18 ft) based on the photograph and its jaws. --Anshelm '77 19:51, 8 October 2006 (UTC)
An encyclopedia I have says that 'most are between 6 and 7,50 m'; one noteable specimen measured 6,40 m and weighed 3,2 tons, another was 5,20 m long and weighed 1,3 tons. It also speaks of a much larger one being captured in Port Fairey (Australia) in the late 19th century; supposedly that one measured a staggering 11 m. The encyclopedia, Purnell's Encyclopedia of Animal Life, is pretty old (1970), so I this info may have been debunked since. Also, the fact that featured a very inaccurate text about dinosaurs (using the name Brontosaurus, saying T.rex was 17 m long, misspelling Triceratops as Tricaterops) kinda harms its believability, although it can be explained because the writer probably knew far more about zoology than paleontology. Interestingly, it does state that claims of 12 m or more are most likely false, despite that apparently not implausible listing of 11 m being pretty close to that. I suppose it could be true that there were bigger great whites in the past, but now they don't live to that size (presumably because of man). Isn't the same happening to the blue whale? Jerkov 21:19, 15 June 2006 (UTC) True and if you let an animal like the Great White shark live for long enough, it could probably grow to sizes like tkis. We dont know alot about White Sharks as it is so this could be true. Nasty wording
Under size. " - of this 'theory' that the New Brunswick shark was a basking shark is without any proof, speculative, dismissive of the original witnesses and therefore arrogant to say the least" Pretty unnecessary. DPDC —Preceding unsigned comment added by 70.116.4.108 (talk) 04:38, 21 August 2008 (UTC)
Pictures
In my (online) research in the size of Great White Sharks these are the two most convincing pictures I've found of specimens who were supposedly around 6 meters in length: [1] and [2]. Especially the last one seems 6 meters in length, although the Vic Hislop shark on the first picture is definitely the heaviest specimen ever caught. --24.132.210.122 (talk) 06:28, 27 March 2010 (UTC)
Longevity
Great Whites are known to live more than 30 years old. Many sources say 36 years; but another source said this to be erroneus, and that there were verified cases of individuals 31–32 years old. The information on the subject is limited, so it's more than likely to live much older than this. I could imagine an animal this big to live for 50–80 years, but that's just me. Anshelm '77
Question
The article mentions only one failed attempt at keeping a great white in captivity. What about this? http://www.mbayaq.org/cr/whiteshark.asp
The longest attempt was 198 days, breaking the previous record of 16 days, by the Monterey Bay (california) Aquarium. The female shark, who was injured when captured by a fisherman, had grown to large for the aquarium and was attacking other sharks in her tank (article references a soupfin).
There is a documentary airing on PBS stations about the Monterey Bay Aquarium, with an excellent website ( http://www.pbs.org/wnet/nature/oceansinglass/index.html ), that retells the story of the shark's captivity, as well as information about the shark after its release: http://www.pbs.org/wnet/nature/oceansinglass/whiteshark.html
Google: "great white captivity" http://dsc.discovery.com/news/briefs/20041004/shark.html http://dsc.discovery.com/news/briefs/20050307/shark.html http://www.msnbc.msn.com/id/7351538/
Megalodon?
This article says that they are related to the extinct Megalodon, and then says that they are not. This is probably the result of a poor edit. Someone should certianly try to find a reliable refrence that confirms either side. Great Green Arkelseizure 05:31, 14 January 2006 (UTC) THEY ARE NOT REAL WOW! THEY used to exist but not anymore JWC
Shouldn't your name be Great Green ArkLEseizure, Great Green Arkelseizure? Notreallydavid 00:54, 29 November 2006 (UTC)
Why do great white sharks attack people?
White sharks attack people because they are primarily ambush predators. Which means that they attack in one swift blow from beneath the water at high speeds. At 50 or a 100 feet below the surface, a human on a surfboard looks a lot like a cape fur or elephant seal. A great white needs thousands of calories to keep it's body temp a few degress higher than it's surounding environment, and I can guarantee you they don't get it by eating humans. AWH
I belong to Shark Rehabilitators of New South Wales, Australia. To prove that sharks are misunderstood creatures, a hundred of our volunteers bobbed up and down in shark infested waters and only 6 were eaten (I took part in this experiment and was lucky enough to hug a shark without any ill event). In the same experiment but using 100 seals, 62 seals were eaten. Sharks mean no harm to the human race. Their persecution should stop. —Preceding unsigned comment added by Edith Smitters (talk • contribs) 01:39, 3 June 2010 (UTC)
they are hungry. They need to eat too JWC
My understanding is that sharks (including great whites) do not attack humans because they're hungry. I believe it's generally accepted that:
1) there aren't very many unprovoked attacks on humans
- in 2005, there were only 4 deaths by unprovoked attack by ANY type of shark worldwide (see http://www.flmnh.ufl.edu/fish/sharks/statistics/2005attacksummary.htm)
- in 2005, there were only 11 reported unprovoked attaks by great white sharks, only 1 of which resulted in a fatality (see http://www.flmnh.ufl.edu/fish/sharks/White/whitesharkdecade.html)
2) attacks on humans are usually cases of mistaken identity (such as mistaking a surfer laying on his board as a turtle or seal -- favorite food sources for great whites)
Sharks have some of the greatest sences in the world, and they have 6 of them! I don't believe that a shark would mistake a human on a surf board for a seal. They have great farsight, terrible nearsight, they have a great sence of smell, and they have the electro sence. They know what a seal smells like and how much electrical pulses it sends out, they wouldn't easily mistake that for a human. Bcody 01:46, 3 August 2006 (UTC)
- i've never heard that before. do you have a cite for that? Mapetite526 16:22, 21 September 2006 (UTC)
- My understanding is that sharks attack people because they are curious about them, and a shark probes/tests strange items by biting it. Due to the size of the great white, a probing bite would still often prove fatal to a human.--Caliga10 16:32, 21 September 2006 (UTC)
Sure, many times sharks will "test bite" a person. Most of the time they take a bite, then go away. But there have been different cases. There was one case in H.I. where a tiger shark not only bit a woman who was swimming, but continued to attack her and ate much of her body. There have been cases like this with great whites. If there is a low amount of food in the area, sharks will attack humans and won't stop. You can't just say that it's always a "test bite" Bcody 03:34, 18 November 2006 (UTC)
Great White Sharks do not attack humans for food. Instead they attack humans because of curiousity. Many times sharks are not sure what humans are, they think we are fish. This is why sharks attack humans from my understanding
- White sharks can easily distinguish between seals and people. Their sensory capabilities are incredibly sensitive, can your dog tell the difference between a sheep and a goat, can you? The white shark has a very very sensitive sensory capability and should be able to tell the difference.
- My research suggests that the reason for shark attacks on humans is that they sometimes have "warm brains" and sometimes have "cold brains". (see article) In theory, anyone will agree that if their "cold brains" are numb and incapable of processing sensory input they would THEN not be able to access their incredible sensory capability. This remains an unproven theory. There are major physiological benefits for feeding in warm water and digesting in cold water (see Joe Cech's work on behavioral thermoregulation for sharks in Tomales Bat, CA for more info). Raggz 06:09, 16 September 2007 (UTC)
- PLEASE enough of the shark apologia! They PREFER seals and other marine life BUT if you happen to be there and they are hungry they will strike, and they will back off and wait for you to weaken rather than risk getting themselves hurt by a thrashing, desperate animal. Since you can get out of the water you often live, not out of the shark's preference. Batvette (talk) 11:31, 21 January 2009 (UTC)
Trouble in captivity
A new user wikivandalizer (talk • contribs) added the following paragraph:
- One of the main reasons Great Whites have such trouble in captivity is because they have a "sixth sense" that navigates them through the water based on the earth's magnetic field. When in captivity you will see the Great White bump into walls and such because its sense of navigation has been altered because of the small size of a tank compared to the whole ocean.
I removed it since adding nonsense is part of the MO for other edits the user has made, however I am moving it here in the hope it was the one useful edit made... Any thoughts? --Hansnesse 04:03, 6 March 2006 (UTC)
The size of the body of water should be irrelevant, and even if magnetic navigation is what White Sharks use (recent evidence from satellite tracking esp. shows they spend an unusual amount of time near the surface on long trips, so they may be using visual navigation) the size of the tank won't matter. Plus it sounds like it's confusing the Ampullae of Lorenzini with magnetic navigation. Sharks need a lot of room to roam, and you don't need to go to the lengths of magnetism to find a reason they bump against the edges of their confinement.Wevets 04:47, 8 April 2006 (UTC)
- This magnetic THEORY theory appears in the shark literature, but I cannot now recall any citations. I think that hammerheads were the main species, but I also recall the white shark being SPECULATED about. Pelagic sharks clearly have some form of advanced inter-continental navigation. As far as I know, no one knows how the manage this - but why not magnetic? The first white shark in captivity I recall dying due to tank collisions, and there was official SPECULATION about magnentism. This does not in my opinion belong in the article. Raggz 07:08, 17 September 2007 (UTC)
- I guess I'm not quite following the reasoning. The Earth's magnetic field is still present in the tank, just as it is in the ocean. What magnetic differences due to the tank (glass and acrylic are both non-magnetic) would cause the shark to die? Even if sharks use magnetic navigation (entirely possible,) why would they die from it? Wevets (talk) 17:39, 11 June 2009 (UTC)
Great White Space
Is there any way to remove that ugly big white space at the top? Aplomado - UTC 21:46, 18 April 2006 (UTC)
I see what you did there. --207.237.245.50 (talk) 09:03, 29 November 2008 (UTC)
Amaletz?
Can anyone explain where the name 'Amaletz' comes from? I can only find it in this article and rip-off articles.
- I can't find any source for that name so have removed it. Looks unlikely to be an English language name anyway and the article doesn't list names in other languages. If anybody can give a source for this I'd love to know as it seems to have been copied in in the original article. Yomangani 11:06, 26 June 2006 (UTC)
Spy-hopping?
This is the only shark known to lift its head above the sea surface to gaze at other objects such as prey; this is known as "spy-hopping".
Is spy-hopping actually to look? You'd imagine that eyes designed to interface with water would be mostly useless interfacing with air. If they're build anything like human eyes that is. I'm obviously clueless here and I can't seem to find much about spy-hopping online. This link suggest they focus similarly to a camera, which could be part of the story:
http://www.elasmo-research.org/education/white_shark/vision.htm
Anybody?
- I think we should rewrite this, not sure what is consedered spy-hopping, but this should be consedered lifting its head above the sea surface to me. I will do some more research before I update the text and as for the question, yes I think they actually do this to see, but obviously I'm not sure, whales do a lot of spy-hopping (but I can not even find a article about it? need to ask the whales guys) but it (for whales) have been described as a way to look, but then I know I should not trust documentatries :-). Stefan 00:23, 28 May 2006 (UTC)
Sperm Whale Attack
Is there a source for this? I don't remember reading any account of a sperm whale attack on a Great White Yomangani 18:45, 26 June 2006 (UTC)
- I've seen footage of the attack. Sadly, I can't find online reference to it at present. It does also call into question their status as apex predators. —Preceding unsigned comment added by 124.188.28.202 (talk) 11:47, 26 March 2008 (UTC)
"Frequent" death due to own teeth
That's actually the fisrt I've heard of it. However considering the slow speed at which a white shark will process and digest its food, it's likely that the longer a lost tooth stays in the digestive system, the higher the possibility of damage to the internal structure.
While on the topic of teeth, in the section on Anatomy, some poor misguided individual wrote that the White Shark can retract its teeth like a cat can retract it's claws. This is very incorrect. While a White shark does have theeth that continuously grow in under ones that fall out, the teeth cannot be pulled forward and backward as a shark opens and closes his or her mouth. AWH
"Great whites often swallow their own broken off teeth along with chunks of their prey's flesh. These teeth frequently cause damage to the great white's digestive tract, often resulting in death from infection and blood loss." <-- This sounds like an urban myth. Is there a reference to a study demonstrating this? Andrew Moylan 09:16, 9 August 2006 (UTC)
- These fish are constantly shedding teeth so it would be surprising if tooth-ingestion "often" causes death. Bastie 13:34, 17 February 2007 (UTC)
I assume that unfussy eaters like sharks have powerful digestive systems, so any teeth absorbed would be wholly or partially dissolved. They would lose their sharpness at the very least. 2fort5r (talk) 22:49, 26 January 2009 (UTC)
Sharks are also known for their remarkable immune systems. The idea that incidental swallowing of teeth is killing sharks due to infection seems unlikely, and that's using a generous term. I think this unverified statement has appeared on the main article long enough. 65.12.128.24 (talk) 07:16, 31 August 2009 (UTC)
- In the Niobrara Formation, there was a partially digested mosasaur vertebrae that contained shark teeth in it, and the shark (Cretoxyrhina) digested it just fine. Besides, the adaptation for shedding thousands of teeth would certainly have led to body defenses preventing ruptures of the stomach lining etc. I have also heard of acid-worn fossilized shark teeth, but I can't confirm this. --Spotty 11222 11:31, 31 August 2009 (UTC)
I've got a question
In the distribution of the whales, why do they only live near the continents? Surely they are somewhere in the deep sea as well, no? --Scotteh 17:09, 4 September 2006 (UTC) new message.[[
- They are in the deep open ocean, but are not detected there often. The new tagging technology shows that they are regularly out there, a deep mystery still. Raggz 06:12, 16 September 2007 (UTC)
Sources
This article has a few things listed as, basically a bibliography, but there aren't many in line citations. So when numbers and the like are changed, there's no way to ensure the change is moving us forward. It would be good to add inline references to the article. Does anyone who follows this talk page know which bits of the current article came from which listed book/paper/etc. --Siobhan Hansa 01:18, 23 September 2006 (UTC)
- Yes agree, and no we do not know which refers to what, inline references will be added when we have time. When adding references you basically have to look at a few good one and see if they match the text, if not you update the text to be according to the references and inster the reference. In project sharks we are working on improving the standard of shark articles, I'm sure we will come to this also at some time, but not yet. Please help! Stefan 01:33, 23 September 2006 (UTC)
this is about sharks not whales
Question
Any recent attempts at putting them in captivity?? I always wanted to see one first hand.
- Yes, see this link. Stefan 14:36, 26 September 2006 (UTC)
- Related facts on the current (Oct 2009) female Great White held in captivity at Monterey Bay Aquarium, which was presented by the docent when I visited today: It's about 5'3" (1.58m), estimated at 80 pounds (36.2 kg), estimated at 4 months old. Might be worth posting on the live page. Pegasusgiraffe (talk) 04:52, 11 October 2009 (UTC)pegasusgiraffe
Shark tourism
I think there needs to be something on shark tourism, since the GW is the main shark associated with this booming industry, or is it here and i missed it?--Halaqah 00:41, 23 October 2006 (UTC)
- The majority of this section reads like WP::OR. Can I suggest a clean-up, including facts rather than speculation.Angelstorm (talk) 09:29, 20 August 2009 (UTC)
GW to GA
This is now seleted as collaboration of the week. The goal is GA status. This is my comments on what should be done, please add on to my list and strike out if you fix something.
- need a taxonomy section (see e.g. Oceanic_whitetip_shark)
- Think we should make a 'Relationship to humans' section where we can have 'Great white sharks in captivity' , 'tourism', 'cage diving' and probably Jaws references and so on.
- References!!!!
Take away odd sighting sounds like blog entry, not encyclopedic.- English, I'm sure we need to make the text better (always need that to pass GA)
Stefan 02:07, 24 October 2006 (UTC)
Pictures, that would be nice. Hard to find any, but if that would definitely help, since we only have one photo and a distribution map.chris_huh 16:51, 29 October 2006 (UTC)- Now nice pictures! Stefan 14:19, 9 July 2007 (UTC)
Video
The video linked to from "Video of great white sharks attacking seals" which links to http://www.filecabi.net/video/shark081.html appears to be in copyright violation of content from a BBC programme. I have added a link the video sequence on the BBC web site instead, which is of higher quality and directly from the source. Flux 22:20, 13 November 2006 (UTC).
Picky?
I have read about Great White Sharks being picky with their food. Can anyone say if this is true or not?
- Well, I have read that they usually do not eat what they're not used to. That's why they never eat complete humans, and they never charge twice on humans. —Preceding unsigned comment added by 81.38.137.196 (talk) 01:31, 23 December 2008 (UTC)
picky picky
Great whites are selective in the sense they have preferred prey items, such as seals, dolphins and walruses. They are cautious and will seldom attack anything that they perceive as having seen them and to be making aggressive moves or sorties towards them. So if you see a great white heading towards you, swim towards it and face it! It will keep its distance. This is unlike the behaviour of a reef shark, which though far smaller will launch an attack on animals / humans far larger than itself even though it is quite plain to the shark that its object of attack has seen it and is preparing to defend itself. Hence, great whites will investigate and chomp on things that may be food and will often let go or not presist in the attack if the object does not conform to the expectations of the shark. If you don't taste and feel like a seal it is likely the shark will not eat you. This is presumably what happens in the case of surfers and divers who get a single bite from a great white to themselves or their surfboard after which the shark abandons them. —The preceding unsigned comment was added by 203.27.90.186 (talk) 05:23, 25 January 2007 (UTC).
Semi protect
I do not really like to semi protect pages, but after reverting this page again and again I did a quick check in the history and to me it seams that there is one (rather insignificat) change that a ip user have done from the last month that have not been reverted (OK, I have NOT check each diff, just checked that there is a rv comment after each ip edit), what is the level of vandalism that we normally accept before we semi protect? Stefan 03:18, 29 March 2007 (UTC)
Diet
Someone seems to have vandalized the "Diet" paragraph, it now simply lists: "People", which (although arguably true) is a childish attempt at a joke... 87.212.20.44 12:12, 20 April 2007 (UTC)
- not if you got eaten by one it's not :-P Batvette (talk) 11:34, 21 January 2009 (UTC)
Conversion Problem
The temperature conversion listed when discussing the shark's habitat is incorrect. 30 degrees celsius is considerably more than 75 degrees farenheit. Could someone determine which is correct
- Can not find a source, but an old version states 24C which converts fine to 75F and makes more sense since it is not a tropical shark, so I revert back to that. Stefan 14:17, 9 July 2007 (UTC)
- The white shark literature discusses habitat in terms of surface temperature. In reality, white sharks find the deeper waters to be the same temperature worldwide, even if the surface temperatures vary. Tropical white sharks are thought to spend most of their time in cooler deeper waters. Deep white sharks cannot be detected (except by the very modern tags) so no one really knows how often great white sharks live in the deep waters. We only detect them when near the surface, so surface temperatures are important. Raggz 07:18, 17 September 2007 (UTC)
Sightings
I've tried to find this information everywhere but I can't. Do great whites swim alone or are they in small packs like hammerheads? Usually sightings consist of one shark, but I want to be sure.
- They do congregate, especially in areas like Seal Island by Gansbaai (South Africa) where there can be dozens, but it is generally accepted that they are "solitary". I've also seen them swim together in Mexico, but they don't "buddy-up" as it were, and when confronted with another of its kind will usually respect the distance between them. (ref: Africa Geographic magazine, National Geographic magazine, issues unknown at present, as well as books by Stafford-Dietsch, Taylor, Ferrari). Pterantula 21:37, 27 June 2007 (UTC)
- One sighting off La Jolla California, was of a small group of juvenile white sharks (siblings?) Fishermen have caught what seemed to be a school of small white sharks. There is a video on the internet of an attack on a surfer by two white sharks. There are reports of adults congregating, especially where collectively feeding upon whale carcasses. The scientific literature does not discuss this topic often because their isn't enough information to do so. Raggz 06:19, 16 September 2007 (UTC)
Retractable teeth
I have gone ahead and removed the following from the article:
- Their teeth are unattached to the jaw and are retractable, like a cat's claws, moving into place when the jaw is opened. Their teeth also rotate on their own axis (outward when the jaw is opened, inward when closed). The teeth are linked to pressure and tension-sensing nerve cells. This arrangement seems to give their teeth high tactile sensitivity.
I don't believe it is true, but if anyone has other information I would love to hear it. --TeaDrinker 18:43, 22 June 2007 (UTC)
Shark Smile?
When I looked at the image of the great White Shark I noticed it seemed to smile has anyone else noticed this? —Preceding unsigned comment added by [[User:{{{1}}}|{{{1}}}]] ([[User talk:{{{1}}}|talk]] • [[Special:Contributions/{{{1}}}|contribs]])
- That's because of the yummy fish. Althepal 21:34, 24 June 2007 (UTC)
Nomenclature
— It's my understanding that this animal is called "white shark", not "great white shark" (in the northern hemisphere) - which is the popular term lending weight to the sensationalism surrounding the animal. I would like to see something that claims to be encyclopedic reflect the consensus of the scientific and research community, which seems to be that this is indeed "white shark". I know that popular names are what dilettantes like me will most readily recognize, but there's no reason that a search term "great white" can't refer to the article reflecting the correct name. Or maybe it's not that important, whatever. Pterantula 21:32, 27 June 2007 (UTC)
- [3], [4], [5], [6] and [7] are all resonably scientific references that call it great white shark, there are many calling it white shark also, in wikipedia we use the most common name see WP:NAME which states " Generally, article naming should prefer what the majority of English speakers would most easily recognize, with a reasonable minimum of ambiguity, while at the same time making linking to those articles easy and second nature. " for fish articles we have agreed to use fish base as a base for the name, see guide lines for fish pages at WP:FISH. Stefan 01:45, 4 July 2007 (UTC)
- The Great White Shark is what most people call it. Almost all scientists call them White sharks. This is an encyclopedia, so what the most people call them should be what we call them. If we are editing a scientific journal, this rule would change. Raggz 06:23, 16 September 2007 (UTC)
- I disagree, I think that while this is not a journal article, it is an educational reference source, so should be giving readers the most accurate information that is available. I advocate changing the usage in the article to read white shark, while still keeping the article heading as great white shark, with a section in the beginning discussing usage. Any thoughts? Digsdirt (talk) 02:08, 27 March 2008 (UTC)
67.175.179.166 22:53, 28 July 2007 (UTC)I think the section on "Size" needs to be toned down a bit. I almost fell asleep reading it. It is much to long and I think someone needs to work on condensing it a bit. 67.175.179.166 22:53, 28 July 2007 (UTC)
Sun reference
Can we please remove the reference (NO 2) to the Sun newspaper. It's just its typical sensationalist rubbish. This happens every year someone spots a Basking shark and gets over exited. Because of Jaws the Sun tries to play up the Great White Shark thing to sell paper. If you see the stills they publish on the 20/07/2007 you can clearly see that the fin is rounded like that of a Basking shark. Even if it is not a basking shark it is certainly not a Great White Shark which has a distinctively sharp triangular point to its fin. If you find another,more reliable source cite that. I don't think we should perpetuate the ignorance found in the Sun 81.153.85.7 18:07, 30 July 2007 (UTC)
- Agree, done! --Stefan talk 03:56, 1 August 2007 (UTC)
- Insidently the photographs that appeared in the sun last July did turn out to be genuine photographs of great white sharks... However those photographs were NOT taken off the Cornish Coast but off the South African Coast, the man who sold them to the Sun confessed this to the Daily Star (a rival tabloid to the Sun). As a Biologist I should point out there is actually nothing to stop great white sharks coming to British waters, so the annual tabloid page-filler story might not be that far off the mark (apart from all the 'Jaws' style rubbish that gets linked to it of course). Shearluck (talk) 09:08, 22 July 2008 (UTC)
- Haha, interesting, but still correct to take the reference away even though it was for the wrong reason :-) --Stefan talk 13:09, 22 July 2008 (UTC)
- Insidently the photographs that appeared in the sun last July did turn out to be genuine photographs of great white sharks... However those photographs were NOT taken off the Cornish Coast but off the South African Coast, the man who sold them to the Sun confessed this to the Daily Star (a rival tabloid to the Sun). As a Biologist I should point out there is actually nothing to stop great white sharks coming to British waters, so the annual tabloid page-filler story might not be that far off the mark (apart from all the 'Jaws' style rubbish that gets linked to it of course). Shearluck (talk) 09:08, 22 July 2008 (UTC)
on the BBC documentary PLanet Earth, they describe "6-gilled sharks" as being up to 8 meters long. wouldnt this make them larger than the average great whites size, thus making them the largest known predatory fish? —The preceding unsigned comment was added by 71.87.2.48 (talk)
- Six-gills are indeed large, and they do feed on marine mammals (many believe these are scavenged). We know very little about the large six-gills because they live in such deep water. Many harmless sharks will bite you if you hold onto their tail, I think that the six-gill have bitten two or three people. A seven-gill bit a co-worker who had grabbed it by the tail - don't do this with most sharks... The white shark is large, but not the largest of sharks (see whale shark).
- The BBC documentary Planet Earth also has footage of a whale shark feeding on fish, I don't know the definition of 'predatory', but does this make the whale shark the largest known predatory fish?80.7.122.153 (talk) 12:13, 31 May 2008 (UTC)anon
DATE OF PHOTO
Third photo down, picture looks like it was taken in 1907 not 1997, it says 'Great white shark caught off Hualien County, Taiwan, on May 14, 1997.' this must be an error. --McNoddy 08:24, 20 August 2007 (UTC)
- The image was originally published in black and white, possibly in a newspaper. The date is correct. Mgiganteus1 09:15, 20 August 2007 (UTC)
The photo was first published in a local newspaper as B/W, and I took photo upon it. VicLin (talk) 03:58, 21 September 2009 (UTC) I feel a little bit surprised at the same time a little bit upset that this shark has been quoted by some if not many to be the largest white shark ever recorded whilst I myself don't even think so. Additionally, on my trip in Sep.2009 to the private shark museum where the preserved jaw and fins of this shark were kept, I took some careful examination at these specimens and found them not exceptionally impressive compared to some famous specimens kept in other museums around the world. I concluded that this shark was no way longer than 19~20 feet. VicLin (talk) 04:09, 21 September 2009 (UTC)
Ampullae of Lorenzini
"Every time a living creature moves it generates an electrical field and great whites are so sensitive they can detect half a billionth of a volt. This is equivalent to detecting a flashlight battery from 1,600 kilometres (1,000 miles) away"
That second sentence is incorrect. The function of the Ampullae is to detect differences in voltage. At the distance cited (1000 miles), the voltage difference over 1cm is completely negligible. (with 1/r2 attenuation, the difference over 1cm would be ~1e-36V). —Preceding unsigned comment added by Unagiflum (talk • contribs) 18:55, 6 September 2007 (UTC)
- John McCosker wrote that the electrical field of a 1,000 mile-long copper wire hooked up to a size D flashlight battery is estimated to be detectible. Should i put this in? (Ellis and McCosker 1991 page 72). Raggz 06:36, 16 September 2007 (UTC)
Carcharodon
Shouldn't Carcharodon have its own page? The white shark isn't the only species currently assigned to this genus. —Preceding unsigned comment added by 76.8.194.226 (talk) 22:03, 19 September 2007 (UTC)
- Yes it should in principle, feel free to make it, this is a wiki, but since we have pages for both Carcharodon carcharias and Carcharodon megalodon there is not much need, the page will be very short or have lots of overlapping info. Maybe the redirect should go to Lamnidae instead, not sure. --Stefan talk 03:50, 20 September 2007 (UTC)
- No, not unless you have material not in either article. If so, then Yes.
- I agree with Stefan, consider moving it to a section under Lamnidae? The sharks article doesn't link to shark, and the Lamnidae is a stub. These are areas that in my opinion, are of a higher priority. But in the end, inclusion of Carcharodonis your editorial decision. The phylogeny of Carcharodon might be a good focus, it is not in other articles. Who says that this genus is called "white sharks"? I've not heard that and am curious? Raggz 18:27, 21 September 2007 (UTC)
- I have already done the re redirected it to Lamnidae, I do not like to redirect to sections since it will break if someone renames the section and since Lamnidae is so short I redirect to the whole page. --Stefan talk 23:41, 21 September 2007 (UTC)
Great white shark
This photo looks a bit unreal to me. Its either a computer drawing, or a real picture that has overprocessed in Photoshop. There is a better and more natural version that I recommend for uplaoding White shark.jpg--Albert Kok 18:37, 23 September 2007 (UTC)
15 pictures!!!
I suggest that we take away a few pictures from this page? There are 7 pictures that shows a shark from above not showing much of the shark and all doing about the same, can we take away at least a few?? I tried but was reverted after 15 minutes from the user that have taken most of the pictures I talk about. Comments anyone? --Stefan talk 15:07, 25 September 2007 (UTC)
- I concur, and have again removed a few images which seemed redundant or unnecessary --TeaDrinker 20:37, 7 October 2007 (UTC)
Add more pictures please!!!~Elvis Topia!!!
Length
The length measure in this article is listed with both feet and meters as units. Could someone determine the correct unit and measure? ~~ —Preceding unsigned comment added by 129.89.24.99 (talk) 21:18, 24 October 2007 (UTC)
Protective clothing
The article mentions protective clothing as a safe contermeasure against white shark attacks. This is wrong. I've seen a documentary where scientists tested just that, using a dummy with protective clothing. While the clothing did protect the dummy against the bites, the shark's bite was so strong (jaw strenght) that it crushed the dummy. However the clothing still showed eficiency against bites from other shark species. Point is that like many aligators or crocs, the white has a jaw strong enough to crush a human body. --Netshark (talk) 11:30, 10 December 2007 (UTC)
Article title
Should not the article name be capitalized, "Great White Shark" it is the proper name of the species, see Capitalization! Chessy999 (talk) 10:40, 25 December 2007 (UTC)
- Please read, for context, the policy document at Wikipedia:Naming conventions and its child, Wikipedia:Naming conventions (fauna). Then, most importantly, read Wikipedia:WikiProject Fishes#Article titles for the answer as to why not. Finally, just as a pointer, I think you might also benefit from reviewing Wikipedia:Manual of Style#Section headings. Cheers! — Dave (Talk) 21:15, 25 December 2007 (UTC)
Their flesh is valuable?
I remember reading that Great Whites excrete waste through their skin, and that makes their flesh practically inedible to humans. Can anybody verify that perhaps I'm not thinking of some other predatory fish? —Preceding unsigned comment added by 71.80.122.77 (talk) 19:27, 13 February 2008 (UTC)
- That sounds like you mixed the Great White up with Somniosus microcephalus, the Greenland shark, one of the Squaliformes! The latter species doesn't have kidneys, whose purpose is to maintain the homeostatic balance of bodily fluids by filtering and secreting metabolites and minerals from the blood, excreting them as urine. Instead the Greenland shark's metabolic waste products are excreted through their flesh.
- Said flesh is initially poisonous and unfit for human consumption due to toxic Trimethylamine N-oxide and thus the shark species is only valuable for liver and fins to the fishing industry. But in Greenland and Iceland the flesh is consumed after a months long rotting and drying process as a local delicacy called Hákarl. - Darshu —Preceding unsigned comment added by 91.16.57.140 (talk) 14:48, 17 March 2008 (UTC)
Aha! I knew there was one. Thanks. —Preceding unsigned comment added by 71.80.122.77 (talk) 23:22, 26 March 2008 (UTC)
Well I have never eaten white shark flesh, but do know some fishermen that have. According to them, white shark flesh is tasteless just like longfin mako, especially big ones. But it is not saying their flesh is totally valueless.VicLin (talk) 18:14, 21 September 2009 (UTC)VicLin
Tonne and short-ton
A short ton is 2000 lbs. A metric tonne is 1000 kgs, or ~2200 pounds. In the article regarding weight it says they can get up to 2 tonnes (1.75 short tonnes). Can someone clean this up? Should it be 2 tonnes (2.2 short-tons) or should it be 1.75 tonnes (2 short-tons)? —Preceding unsigned comment added by 207.210.51.113 (talk) 02:01, 20 March 2008 (UTC)
Metric?
Lets stop reverting each other and discuss metric vs. non metric. I have checked a few of the references (not all) and the majority seams to be in metric. There are at least 3 users willing to revert to go back to metric and one that want to change to imperial? Lets discuss and explain to use why metric should not be stated first? What is 'Stanford Report'? and why does it matter? --Stefan talk 03:47, 25 April 2008 (UTC)
Megalodon
While I realise that a lot of Editors are deeply interested in the Megalodon, I fail to see the relevance here. Not only has the relation been thrown into seriouc doubt, but the bulk of the material seems to deal with the Megalodon itself. Considering that there is only a mention of the more credible I. Hastalis - I. Escheri - C. Carcharias link, it would seem that the mention is the work of a few over-zealous Megalodon-enthusiasts. I suggest it be replaced with an evolution section, making only a passing reference to the Megalodon.--THobern 08:02, 4 May 2008 (UTC)
Size
"Reaching lengths of more than 6 m (20 ft)"
The biggest caught Great White Shark wasn't even 20 ft, The record length is 19 ft, were does "Reaching lengths of more than 6 m (20 ft)" come from? and 19 ft is pushing it most sites say 16 ft was the largest ever caught. —Preceding unsigned comment added by Rex550 (talk • contribs) .
- Did you read the size section futher down?
“ | The largest specimen Ellis and McCosker endorse as reliably measured was 6.4 m (21 ft) long, caught in Cuban waters in 1945; though confident in their opinion, Ellis and McCosker note other experts have argued this individual might have been a few feet shorter. There have since been claims of larger great white sharks, but, as Ellis and McCosker note, verification is often lacking and these extraordinarily large great white sharks have, upon examination, all proved under the 20-21 ft limit. For example, a much-publicized female great white said to be 7.13 m (23.4 ft) was fished in Malta in 1987 by Alfredo Cutajar. In their book, Ellis and McCosker agree this shark seemed to be larger than average, but they did not endorse the 7.13 m (23.4 ft) measurement. In the years since, experts eventually found reason to doubt the claim, due in no small part to conflicting accounts offered by Cutajar and others. A BBC photo analyst concluded that even "allowing for error ... the shark is concluded to be in the 18.3 ft (5.6 m) range and in no way approaches the 23 ft (7.0 m) reported by Abela." (as in original)[7]
According to the Canadian Shark Research Centre, the largest accurately measured great white shark was a female caught in August 1988 at Prince Edward Island off the Canadian (North Atlantic) coast and measured 6.1 m (20 ft). The shark was caught by David McKendrick, a local resident from Alberton, West Prince.[7] |
” |
See the references, they are quite good. So that is where it comes from. --Stefan talk 02:00, 14 May 2008 (UTC)
- The Alberton specimen (caught in 1983 rather than '88) measured 5.76 m (18 ft 10¾ in). Scroll down for it --Anshelm '77 (talk) 23:03, 12 February 2009 (UTC)
- Indeed, I also suspected these sharks to be the same. I suggest we change it. --24.132.210.122 (talk) 12:11, 21 May 2010 (UTC)
Range map
The range map attached to the taxobox does not seem to agree with the distribution and range section of the article, particularly relating to migrations. Neil916 (Talk) 22:55, 20 June 2008 (UTC)
Intrauterine Cannabalism - False!
This article states that the Great White experiences intrauterine cannabalism, where the fetuses inside the mother's uterus will feed off each other until birth.
This is not true. It is something that happens with the ragged tooth shark, but not Great Whites.
Meredithand (talk) 22:51, 27 July 2008 (UTC)MLA
Megalodon
I brought this up before, but nobody replied. The Megalodon content is almost entirely irrelevant; more about the Megalodon than the very questionable link to the Great White. I would suggest an evolution section as a replacement, but for now, if nobody objects, I'll remove the "sharkcruft".--203.129.39.91 (talk) 10:26, 11 August 2008 (UTC)
- That would be ok, a more extensive analysis of the species evolution is needed. Good luck. Enlil Ninlil (talk) 23:44, 19 August 2008 (UTC)
- Cheers. I'll dig out some of the relevant literature and see what I can do. Any thoughts on whether I should post a draft here?--THobern 07:55, 26 August 2008 (UTC) —Preceding unsigned comment added by THobern (talk • contribs)
- I say no need for a draft, remove the 'cruft' and add whatever you can add about evolution, it can not get any worse :-) --Stefan talk 09:03, 26 August 2008 (UTC)
- Cheers. I'll dig out some of the relevant literature and see what I can do. Any thoughts on whether I should post a draft here?--THobern 07:55, 26 August 2008 (UTC) —Preceding unsigned comment added by THobern (talk • contribs)
The range map is wrong
On the IUCN Red List of http://www.iucnredlist.org/details/full/3855/0 is written that is also present in Cyprus, Malta, Turkey and Greece. All areas that are not highlighted in the range map. Also on http://www.flmnh.ufl.edu/fish/Gallery/Descript/Whiteshark/whiteshark.html is on a different area. I note that even in other languages is the same mistake. Perhaps someone was wrong and the other went behind him.
Someone can correct the area because I have not capable? Thank you.
Woodward,(italian user) Dec 6 2008 —Preceding unsigned comment added by 82.60.12.22 (talk) 09:30, 6 December 2008 (UTC)
Range map colour
I have written to user Zoologist to see if the range map colour can be corrected to blue. GrahamBould (talk) 22:12, 5 March 2009 (UTC)
- I see very few differences between the original range map
- and the new red one
File:Wiki-Carcharodon carcharias.png
- except for red/blue color, a white spot between china and japan, coco island (or is that galapagos) is visible on the blue and resolution. Do we really need a range map that is 4,677 × 2,079? I would just change back and was planning to be forgot. Did not understand how the new one was improved. What really should be done is make a dual shaded one with some of the open ocean/migration areas also shown. --Stefan talk 01:57, 16 March 2009 (UTC)
Fossil evidence
http://www.sciencedaily.com/releases/2009/03/090312174733.htm Please read and seewhat you all think. Enlil Ninlil (talk) 00:25, 16 March 2009 (UTC)
kassandra brill —Preceding unsigned comment added by 69.67.2.48 (talk) 11:55, 21 March 2009 (UTC)
- Oh, yes, The Sacaco dentition. Well, this has been pretty much known already. The only really new thing is that the shark was 20 years old when it died by counting light and dark bands in the shark's vertebrae, which calcify with age. What this unique fossil shows us, is that the extinct broad-tooth mako, Cosmopolitodus hastalis, is the Great White's ancestor, not the Megalodon. Here is a link to the Fossil Wiki article on the dentition. It is one of the comprehensive articles on the dentition. Sacaco dentition --Spotty11222 (talk) 12:40, 21 March 2009 (UTC)
Reproduction
It appears that the section on reproduction has the mutually-exclusive claims that birth has never been observed, and that a female needs to "go fast to go fast to prevent herself from eating her young after they are born." Considering that the second claim is vague, over-simply worded, and already requiring citation, I recommend its removal in favor of the former claim. —Preceding unsigned comment added by 128.170.62.95 (talk) 20:49, 14 August 2009 (UTC)
how thay move
i want to know how white sharks move
how thay move
i want to know how white sharks move —Preceding unsigned comment added by 68.0.220.68 (talk) 18:50, 27 October 2009 (UTC)
Point Fairy shark
Page 50 of Ellis and McCoskers book states that the Point Fairy shark was originally recorded as 36ft not 26ft. Bobisbob2 (talk) 20:34, 29 October 2009 (UTC)
U.S.S. Indenapolis
When the U.S.S. Indenapolis sunk in 1945, sharks attacked and killed most of the surviving crew. 1100 men went into the water. One week later, 300 some came out. Most of the sharks responciple for the deaths are tiger and makos but some of them were Great Whites. —Preceding unsigned comment added by 208.111.238.122 (talk) 01:52, 4 November 2009 (UTC)
- Most of the shark attacks on the Indianapolis crew were by oceanic whitetip sharks. See USS Indianapolis (CA-35) for details. -- Yzx (talk) 03:19, 4 November 2009 (UTC)
The number of shark attacks on humans has not been significant enough to warrant a real scare from beach goers and boaters.
Great white sharks serve a significant purpose in today’s ecology. You can be sure that they feed on meat such as seals, sea lions, and turtles. They even feed on injured, sick, and diseased, thus cleaning up the ocean and future spreading of plague.
Scientists have studied great white sharks for many years and each year discovers more interesting facts about the life of the white shark.
While great white sharks have become a protected species, man is still the species biggest threat. Whether the fish are killed while netting bait fish or accident caught via long line fishing for swordfish and other commercial species, the great white shark continually is at risk.
While a white shark has poor vision, it become susceptible to such risk and causes death many time each year.
Here are some facts about Great White Sharks:
Distribution and Habitat Of Great White Sharks
Great White Sharks live in almost all the cold or temperate waters of the
planet, with greater concentrations in the southern coasts of Australia , in South Africa , California , and to a degree in the Central Mediterranean and the Adriatic Sea . The densest known population is found around Dyer Island , South Africa where up to 31 different white sharks have been documented by Michael Scholl of White Shark Trust in a single day[citation needed]. It can be also found in tropical waters like those of the Caribbean and has been recorded off Mauritius . It is also a pelagic fish, but recorded or observed mostly in coastal waters in the presence of rich game like otariids, cetaceans, other sharks and large bony fish species. It is considered an open-ocean dweller and is found from the surface to as deep as 1280 meters, but is most often seen near the surface.
Anatomy and appearance
An illustration of the Great White sharkThe Great White Shark has a robust large conical-shaped snout. It has almost the same size upper and lower lobes on the tail fin (like most mackerel shark, but unlike most other sharks). It is pale to dark gray and has a white belly.
Great Whites, like many other sharks, have rows of teeth behind the main ones, allowing any that break off to be rapidly replaced. Their teeth are unattached to the jaw and are retractable, like a cat's claws, moving into place when the jaw is opened. Their teeth also rotate on their own axis (outward when the jaw is opened, inward when closed). The teeth are linked to pressure and tensor-sensing nerve cells. This arrangement seems to give their teeth high tactile sensitivity.
Size Of Great White Sharks While the average length of a Great White is 4 to 5 m (13 to 16 ft), females generally being larger than males, the question of the maximum size of Great White sharks has been subject to much debate, conjecture, and misinformation. Richard Ellis and John E. McCosker, both academic shark experts, devote a full chapter in their book The Great White Shark (1991) to analysis of various accounts of extreme size.
Today, most experts contend that the Great White's "normal" maximum size is about 6 m (20 ft), with a maximum weight of about 1900 kg (4200 lb). Any claims much beyond these limits are generally regarded as doubtful, and are closely scrutinized.
For some decades, many standard ichthyology reference books listed an 11 m (36 feet) Great White captured in south Australian waters near Port Fairy in the 1870s as the largest individual. While this was the commonly accepted maximum size, reports of 7.5 to 10 m (25 to 30 ft) Great Whites were common and often deemed credible.
Some researchers questioned the reliability of this measurement of the Port Fairy shark, noting it was much larger than any other accurately reported Great White. The question was settled in the 1970s, when J.E. Reynolds examined the Port Fairy shark's jaws and "found that the Port Fairy shark was of the order of 5 m (17 feet) in length".[1]
Ellis and McCosker write that "the largest White Sharks accurately measured range between 19 and 21 feet [about 5.8 to 6.4 meters], and there are some questionable 23-footers [about 7 meters] in the popular — but not the scientific — literature". Furthermore, they add that "these giants seem to disappear when a responsible observer approaches with a tape measure." (For more about legendary measurements, see The Submarine (shark)).
The largest specimen Ellis and McCosker endorse as reliably measured was 6.4 m (21 ft) long, caught in Cuban waters in 1945 (they note, however, that other experts have argued this individual might have been a few feet shorter). There have since been claims of larger Great Whites, but, as Ellis and McCosker note, verification is often lacking and these extraordinarily large Great Whites have, upon examination, all proved of average size. For example, a female said to be 7.13 meters (over 23 feet) was fished in Malta in 1987 by Alfredo Cutajar. In their book, Ellis and McCosker agree this shark seemed to be larger than average, but they did not endorse the measurement. In the years since, experts eventually found reason to doubt the claim, due in no small part to conflicting accounts offered by Cutajar and others. A BBC photo analyst concluded that even "allowing for error ... the shark is concluded to be in the 18 ft [5.5m] range and NO WAY approaches the 23 ft [7 m] reported by Abela." (as in original) [2]
According to the Canadian Shark Research Centre, the largest accurately measured Great White shark was a female caught in August 1983 at Prince Edward Island off the Canadian coast ( North Atlantic ) and measured 6.1 m (20 ft). The shark was caught by David McKendrick a local resident from Alberton, West Prince[citation needed].
The question of maximum weight is complicated by an unresolved question: when weighing a Great White, does one account for the weight of the shark's recent meals? With a single bite, a Great White can take in up to 14 kg (30 lb) of flesh, and can gorge on several hundred pounds or kilograms of food.
Ellis and McCosker write that "it is likely that [Great White] sharks can weigh as much as 2 tons", but also note that the largest verified examples weigh in at about 1.75 short tons (1.6 metric tons).
The largest Great White recognized by the International Game Fish Association is one landed by Alf Dean in south Australian waters in 1959, weighing 1208 kg (2664 lb). Several larger Great Whites caught by anglers have since been verified, but were later disallowed from formal recognition by IGFA monitors for rules violations.
Diet Great White sharks primarily eat fish, smaller sharks, turtles, dolphins, and pinnipeds such as seals and sea lions. They are apex predators; the only animals known to attack them are other Great Whites, sperm whales and orcas.
Great Whites are partially warm-blooded, keeping most of their body up to 14°C above the surrounding water, which would suggest a high metabolism. Despite that, the few estimates that have been made, suggest they're economical with their calories and can go weeks between meals. Due to problems keeping Great Whites in captivity, no concrete figures for this exist.
Behavior White sharks' reputation as ferocious predators is well-earned, yet they are not (as was once believed) indiscriminate "eating machines". They typically hunt using an "ambush" technique, taking their prey by surprise from the bottom. Sometime they swim so fast that they actually jump out of the water while chasing/attacking seals. This is one of only a few sharks that can jump fully out of the water, the others are Thresher shark, Shortfin mako, Longfin mako, Spinner shark, Blacktip reef shark, Salmon shark, Porbeagle shark and the Copper shark. This is the only shark known to regularly lift its head above the sea surface to gaze at other objects such as prey; this is known as "spy-hopping", this behaviour have also been seen in at least one group of Blacktip reef sharks but this might be a behaviour learned from interaction with humans. It is theorized that the shark may also be able to smell better this way, since smells travel through air faster than through water.
More than any documented attack, Steven Spielberg's 1975 film Jaws provided the Great White with the image of a "man eater" in the public mind. While Great Whites have been responsible for occasional fatalities in humans, they typically do not target humans as prey: for example, in the Mediterranean Sea there were 31 confirmed attacks against humans in the last two centuries, only a small number of them deadly. Many incidents seem to be caused by the animals "test-biting" out of curiosity. Great White Sharks are known to perform test-biting with buoys, flotsam, and other unfamiliar objects as well, and might grab a human or a surfboard with their mouth (their only tactile organ) in order to determine what kind of object it might be.
Other incidents seem to be cases of mistaken identity, in which a shark ambushes a bather or surfer, usually from below, believing the silhouette it sees on the surface is a seal. Many attacks occur in waters with low visibility, or other situations in which the shark's senses are impaired. It has been speculated that the species typically does not like the taste of humans, or at least that the taste is unfamiliar.
Humans, in any case, are not healthy for Great White sharks to eat because the sharks' digestion is too slow to cope with the human body's high ratio of bone to muscle and fat. Accordingly, in most recorded attacks, Great Whites have broken off contact after the first bite. Fatalities are usually caused by loss of blood from the initial limb injury rather than from critical organ loss or from whole consumption.
Biologist Douglas Long writes that the Great White's "role as a menace is exaggerated; more people are killed in the U.S. each year by dogs than have been killed by White sharks in the last 100 years." [3]
Many "shark repellents" have been tested, some using scent, others using protective clothing, but to date the most effective is an electronic beacon worn by the diver/surfer that creates an electric field which disturbs the shark's sensitive electro-receptive sense, the Ampullae of Lorenzini.
Capabilities Great Whites like all other sharks have an extra sense given by the Ampullae of Lorenzini, which enables them to detect the electromagnetic field emitted by the movement of living animals. A Great White's sense of sight is useful, but the shark does not depend on it. A shark primarily uses its extra senses (i.e, Electrosense and Mechanosense) to locate prey from far off. Then, the shark uses smell and hearing to further verify that its target is food. At close range, the shark utilizes sight for the attack. The shark will often in ambush deliver a massive disabling bite and then back off to allow the prey to expire. This tactic allows the animal to avoid combat with dangerous prey, such as sea lions. It also has allowed occasional rescue of humans bitten by the animal, though it appears to attack humans mostly in error.
Reproduction There is still a great deal that is unknown about Great White behavior, such as mating habits. Birth has never been observed, but several pregnant females have been examined. Great Whites are ovoviviparous, the eggs developing in the female's uterus, hatching there and continuing to develop until they are born, at which point they are perfectly capable predators. The embryos can feed off unfecundated eggs. The delivery takes place in the period transitioning spring and summer.
The young, which number 8–9 (with a maximum of perhaps 14) for a single delivery, are about 1.5 m (5 ft) long when born. Their teeth are provided with small side cusps. They grow rapidly, reaching 2 meters of length in the first year of life. Almost nothing, however, is known about how and where the Great White mates. It should be noted that there is some evidence that points to the near-soporific effect as the result of a large kill (such as a large whale) possibly inducing mating.
A White Shark can reproduce when a male's length is around 3.8 meters and a female's length is around 4.5 to 5 meters. Their lifespan has not been definitively established, though many sources estimate 30–40 years. It would not be unreasonable to expect such a large marine animal to live longer however.
Great White Sharks in captivity All attempts to keep a Great White Shark in captivity prior to August 1981 lasted 11 days or less. However, that month a Great White broke previous records by lasting 16 days in captivity at SeaWorld San Diego before being released into the wild.
In 1984, the Monterey Bay Aquarium in Monterey , California housed its first Great White, which died after 10 days. In July 2003, Monterey researchers captured a small female and kept it in a large, netted pen off Malibu for five days, where they had the rare success of getting the shark to feed in captivity before it was released. [5] It was not until September 2004 that the aquarium made history by becoming the first aquarium in the world to place a Great White on long-term exhibit. The young female, who was caught off the coast of Orange County, was kept in the aquarium's massive 1 million-gallon Outer Bay exhibit for 198 days before her successful release back to the wild in March 2005. She was tracked for 30 days after her release.
Probably the most famous Great White to be kept in captivity was a female named " Sandy ," which in August 1980 became the first and only Great White to be housed at the Steinhart Aquarium in San Francisco , California . She was returned to the wild because she would not eat anything given to her and constantly bumped against the walls
The white shark lives mainly in the upper part of the water column, near the shore. However, it ranges from the surf line to well offshore and from the surface and to depths of over 250m (775ft). This shark commonly patrols small coastal islands inhabited by pinnipeds (seals, sea lions and walruses), offshore reefs, banks and rocky headlands where there is deepwater close to shore. The white shark usually cruises either just off the bottom or near the surface.Before movies such as Jaws and Shark Attack Movie, Great White Sharks did not have much of a reputation in the public eye. —Preceding unsigned comment added by 74.100.61.249 (talk) 23:55, 10 January 2010 (UTC)
The number of shark attacks on humans has not been significant enough to warrant a real scare from beach goers and boaters.
Great white sharks serve a significant purpose in today’s ecology. You can be sure that they feed on meat such as seals, sea lions, and turtles. They even feed on injured, sick, and diseased, thus cleaning up the ocean and future spreading of plague.
Scientists have studied great white sharks for many years and each year discovers more interesting facts about the life of the white shark.
While great white sharks have become a protected species, man is still the species biggest threat. Whether the fish are killed while netting bait fish or accident caught via long line fishing for swordfish and other commercial species, the great white shark continually is at risk.
While a white shark has poor vision, it become susceptible to such risk and causes death many time each year.
Here are some facts about Great White Sharks:
Distribution and Habitat Of Great White Sharks
Great White Sharks live in almost all the cold or temperate waters of the
planet, with greater concentrations in the southern coasts of Australia , in South Africa , California , and to a degree in the Central Mediterranean and the Adriatic Sea . The densest known population is found around Dyer Island , South Africa where up to 31 different white sharks have been documented by Michael Scholl of White Shark Trust in a single day[citation needed]. It can be also found in tropical waters like those of the Caribbean and has been recorded off Mauritius . It is also a pelagic fish, but recorded or observed mostly in coastal waters in the presence of rich game like otariids, cetaceans, other sharks and large bony fish species. It is considered an open-ocean dweller and is found from the surface to as deep as 1280 meters, but is most often seen near the surface.
Anatomy and appearance
An illustration of the Great White sharkThe Great White Shark has a robust large conical-shaped snout. It has almost the same size upper and lower lobes on the tail fin (like most mackerel shark, but unlike most other sharks). It is pale to dark gray and has a white belly.
Great Whites, like many other sharks, have rows of teeth behind the main ones, allowing any that break off to be rapidly replaced. Their teeth are unattached to the jaw and are retractable, like a cat's claws, moving into place when the jaw is opened. Their teeth also rotate on their own axis (outward when the jaw is opened, inward when closed). The teeth are linked to pressure and tensor-sensing nerve cells. This arrangement seems to give their teeth high tactile sensitivity.
Size Of Great White Sharks While the average length of a Great White is 4 to 5 m (13 to 16 ft), females generally being larger than males, the question of the maximum size of Great White sharks has been subject to much debate, conjecture, and misinformation. Richard Ellis and John E. McCosker, both academic shark experts, devote a full chapter in their book The Great White Shark (1991) to analysis of various accounts of extreme size.
Today, most experts contend that the Great White's "normal" maximum size is about 6 m (20 ft), with a maximum weight of about 1900 kg (4200 lb). Any claims much beyond these limits are generally regarded as doubtful, and are closely scrutinized.
For some decades, many standard ichthyology reference books listed an 11 m (36 feet) Great White captured in south Australian waters near Port Fairy in the 1870s as the largest individual. While this was the commonly accepted maximum size, reports of 7.5 to 10 m (25 to 30 ft) Great Whites were common and often deemed credible.
Some researchers questioned the reliability of this measurement of the Port Fairy shark, noting it was much larger than any other accurately reported Great White. The question was settled in the 1970s, when J.E. Reynolds examined the Port Fairy shark's jaws and "found that the Port Fairy shark was of the order of 5 m (17 feet) in length".[1]
Ellis and McCosker write that "the largest White Sharks accurately measured range between 19 and 21 feet [about 5.8 to 6.4 meters], and there are some questionable 23-footers [about 7 meters] in the popular — but not the scientific — literature". Furthermore, they add that "these giants seem to disappear when a responsible observer approaches with a tape measure." (For more about legendary measurements, see The Submarine (shark)).
The largest specimen Ellis and McCosker endorse as reliably measured was 6.4 m (21 ft) long, caught in Cuban waters in 1945 (they note, however, that other experts have argued this individual might have been a few feet shorter). There have since been claims of larger Great Whites, but, as Ellis and McCosker note, verification is often lacking and these extraordinarily large Great Whites have, upon examination, all proved of average size. For example, a female said to be 7.13 meters (over 23 feet) was fished in Malta in 1987 by Alfredo Cutajar. In their book, Ellis and McCosker agree this shark seemed to be larger than average, but they did not endorse the measurement. In the years since, experts eventually found reason to doubt the claim, due in no small part to conflicting accounts offered by Cutajar and others. A BBC photo analyst concluded that even "allowing for error ... the shark is concluded to be in the 18 ft [5.5m] range and NO WAY approaches the 23 ft [7 m] reported by Abela." (as in original) [2]
According to the Canadian Shark Research Centre, the largest accurately measured Great White shark was a female caught in August 1983 at Prince Edward Island off the Canadian coast ( North Atlantic ) and measured 6.1 m (20 ft). The shark was caught by David McKendrick a local resident from Alberton, West Prince[citation needed].
The question of maximum weight is complicated by an unresolved question: when weighing a Great White, does one account for the weight of the shark's recent meals? With a single bite, a Great White can take in up to 14 kg (30 lb) of flesh, and can gorge on several hundred pounds or kilograms of food.
Ellis and McCosker write that "it is likely that [Great White] sharks can weigh as much as 2 tons", but also note that the largest verified examples weigh in at about 1.75 short tons (1.6 metric tons).
The largest Great White recognized by the International Game Fish Association is one landed by Alf Dean in south Australian waters in 1959, weighing 1208 kg (2664 lb). Several larger Great Whites caught by anglers have since been verified, but were later disallowed from formal recognition by IGFA monitors for rules violations.
Diet Great White sharks primarily eat fish, smaller sharks, turtles, dolphins, and pinnipeds such as seals and sea lions. They are apex predators; the only animals known to attack them are other Great Whites, sperm whales and orcas.
Great Whites are partially warm-blooded, keeping most of their body up to 14°C above the surrounding water, which would suggest a high metabolism. Despite that, the few estimates that have been made, suggest they're economical with their calories and can go weeks between meals. Due to problems keeping Great Whites in captivity, no concrete figures for this exist.
Behavior White sharks' reputation as ferocious predators is well-earned, yet they are not (as was once believed) indiscriminate "eating machines". They typically hunt using an "ambush" technique, taking their prey by surprise from the bottom. Sometime they swim so fast that they actually jump out of the water while chasing/attacking seals. This is one of only a few sharks that can jump fully out of the water, the others are Thresher shark, Shortfin mako, Longfin mako, Spinner shark, Blacktip reef shark, Salmon shark, Porbeagle shark and the Copper shark. This is the only shark known to regularly lift its head above the sea surface to gaze at other objects such as prey; this is known as "spy-hopping", this behaviour have also been seen in at least one group of Blacktip reef sharks but this might be a behaviour learned from interaction with humans. It is theorized that the shark may also be able to smell better this way, since smells travel through air faster than through water.
More than any documented attack, Steven Spielberg's 1975 film Jaws provided the Great White with the image of a "man eater" in the public mind. While Great Whites have been responsible for occasional fatalities in humans, they typically do not target humans as prey: for example, in the Mediterranean Sea there were 31 confirmed attacks against humans in the last two centuries, only a small number of them deadly. Many incidents seem to be caused by the animals "test-biting" out of curiosity. Great White Sharks are known to perform test-biting with buoys, flotsam, and other unfamiliar objects as well, and might grab a human or a surfboard with their mouth (their only tactile organ) in order to determine what kind of object it might be.
Other incidents seem to be cases of mistaken identity, in which a shark ambushes a bather or surfer, usually from below, believing the silhouette it sees on the surface is a seal. Many attacks occur in waters with low visibility, or other situations in which the shark's senses are impaired. It has been speculated that the species typically does not like the taste of humans, or at least that the taste is unfamiliar.
Humans, in any case, are not healthy for Great White sharks to eat because the sharks' digestion is too slow to cope with the human body's high ratio of bone to muscle and fat. Accordingly, in most recorded attacks, Great Whites have broken off contact after the first bite. Fatalities are usually caused by loss of blood from the initial limb injury rather than from critical organ loss or from whole consumption.
Biologist Douglas Long writes that the Great White's "role as a menace is exaggerated; more people are killed in the U.S. each year by dogs than have been killed by White sharks in the last 100 years." [3]
Many "shark repellents" have been tested, some using scent, others using protective clothing, but to date the most effective is an electronic beacon worn by the diver/surfer that creates an electric field which disturbs the shark's sensitive electro-receptive sense, the Ampullae of Lorenzini.
Capabilities Great Whites like all other sharks have an extra sense given by the Ampullae of Lorenzini, which enables them to detect the electromagnetic field emitted by the movement of living animals. A Great White's sense of sight is useful, but the shark does not depend on it. A shark primarily uses its extra senses (i.e, Electrosense and Mechanosense) to locate prey from far off. Then, the shark uses smell and hearing to further verify that its target is food. At close range, the shark utilizes sight for the attack. The shark will often in ambush deliver a massive disabling bite and then back off to allow the prey to expire. This tactic allows the animal to avoid combat with dangerous prey, such as sea lions. It also has allowed occasional rescue of humans bitten by the animal, though it appears to attack humans mostly in error.
Reproduction There is still a great deal that is unknown about Great White behavior, such as mating habits. Birth has never been observed, but several pregnant females have been examined. Great Whites are ovoviviparous, the eggs developing in the female's uterus, hatching there and continuing to develop until they are born, at which point they are perfectly capable predators. The embryos can feed off unfecundated eggs. The delivery takes place in the period transitioning spring and summer.
The young, which number 8–9 (with a maximum of perhaps 14) for a single delivery, are about 1.5 m (5 ft) long when born. Their teeth are provided with small side cusps. They grow rapidly, reaching 2 meters of length in the first year of life. Almost nothing, however, is known about how and where the Great White mates. It should be noted that there is some evidence that points to the near-soporific effect as the result of a large kill (such as a large whale) possibly inducing mating.
A White Shark can reproduce when a male's length is around 3.8 meters and a female's length is around 4.5 to 5 meters. Their lifespan has not been definitively established, though many sources estimate 30–40 years. It would not be unreasonable to expect such a large marine animal to live longer however.
Great White Sharks in captivity All attempts to keep a Great White Shark in captivity prior to August 1981 lasted 11 days or less. However, that month a Great White broke previous records by lasting 16 days in captivity at SeaWorld San Diego before being released into the wild.
In 1984, the Monterey Bay Aquarium in Monterey , California housed its first Great White, which died after 10 days. In July 2003, Monterey researchers captured a small female and kept it in a large, netted pen off Malibu for five days, where they had the rare success of getting the shark to feed in captivity before it was released. [5] It was not until September 2004 that the aquarium made history by becoming the first aquarium in the world to place a Great White on long-term exhibit. The young female, who was caught off the coast of Orange County, was kept in the aquarium's massive 1 million-gallon Outer Bay exhibit for 198 days before her successful release back to the wild in March 2005. She was tracked for 30 days after her release.
Probably the most famous Great White to be kept in captivity was a female named " Sandy ," which in August 1980 became the first and only Great White to be housed at the Steinhart Aquarium in San Francisco , California . She was returned to the wild because she would not eat anything given to her and constantly bumped against the walls
The white shark lives mainly in the upper part of the water column, near the shore. However, it ranges from the surf line to well offshore and from the surface and to depths of over 250m (775ft). This shark commonly patrols small coastal islands inhabited by pinnipeds (seals, sea lions and walruses), offshore reefs, banks and rocky headlands where there is deepwater close to shore. The white shark usually cruises either just off the bottom or near the surface.Before movies such as Jaws and Shark Attack Movie, Great White Sharks did not have much of a reputation in the public eye. —Preceding unsigned comment added by 74.100.61.249 (talk) 00:00, 11 January 2010 (UTC)
Great white whales
there big! —Preceding unsigned comment added by 74.100.165.117 (talk) 04:08, 9 March 2010 (UTC)
Edit request from 24.180.173.157, 24 April 2010
Pleases delete though there have been numerous undocumented reports of sightings by sailors throughout the ages of sharks approaching and exceeding 30 feet in length from the opening. Rumor and dubious claims don't belong there. 24.180.173.157 (talk) 02:53, 24 April 2010 (UTC)
Tiger Shark comparison edit request
I suggest we change or remove this sentence; "A close contendor in size is the Tiger shark, Galeocerdo cuvier, with largest specimen reported to have been 7.4 metres (24 ft) in length along with a mass of 3,110 kilograms (6,900 lb)."
I don't think the source given is reliable and Tiger Sharks of 7.4 metres in length are totally ludicrous. --24.132.210.122 (talk) 12:16, 21 May 2010 (UTC)
Possible Plagiarism Issue
Request for an expert on this article to look at the section on Ecology and Behavior regarding possible violation of Wikipedia's guidelines on Wikipedia:Plagiarism. While they are indeed footnoted, entire sentences in this section are direct quotations from a 2006 article in the magazine Natural History. In general direct word-for-word duplications are a copyright infringement even if cited unless used in specific ways. For one quick example, please look at "In fact, the social structure of a clan is probably most aptly compared to that of a wolf pack: each member has a clearly established rank..." etc (a direct word-for-word copy from the source), although really most of the first two paragraphs of that section are questionable.
I'm neither a copyright expert nor particularly familiar with this article's editing history, but the change in writing style in this section compared to the rest of the article stood out so I did a quick google search. - Markeer 21:24, 16 October 2010 (UTC)
Mistake in the source?
Celsius to Fahrenheit conversion seems to be wrong in the original article?
Wikipedia article excerpt: "This keeps certain parts of the body (particularly the stomach) at temperatures up to 14 °C (25 °F)[22] above that of the surrounding water —Preceding unsigned comment added by 85.220.81.76 (talk) 03:24, 9 January 2011 (UTC)
- It is not a conversion from 14°C to 25 °F, it is a conversion of 14 degrees difference in C in temperature difference, i.e. 9/5*14(C) = 25(F). --Stefan talk 02:23, 30 January 2011 (UTC)
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