Katharine the great white shark. (Photo: OCEARCH) 
 
 MELBOURNE, Fla. -- Lurking in the depths, Katharine, a 2,300-pound great white shark, has prowled for prey for the past week off the Florida coast — fascinating and alarming local surfers and swimmers. 
 
 Katharine has a red satellite transmitter attached to her dorsal fin. The celebrity predator has generated media coverage across the Sunshine State as satellite "pings" track her trek along the East Coast. She even boasts her own Twitter handle, @Shark_Katharine, and more than 1,300 followers. 
 
 "Definitely not a common inhabitant to our local environment," said Jonathan Shenker, Florida Tech associate professor of biological sciences. "We've got a lot of toothy guys out there — but great whites aren't one of them. 
 
 "I'm just sitting here fascinated about her movements and watching what she'll do next. If she shows up off South Beach Miami, I'm sure you'll see a lot more media attention if she starts cruising the beaches." 
 
 FLORIDA TODAY: Where is Katharine now? 
 
 Katharine was captured and tagged Aug. 19 off of Cape Cod, Mass., by OCEARCH. The organization has tagged about 150 sharks since 2007, and its researchers are tracking about 40 transmitter-equipped great whites, tigers, hammerheads and other species off the Atlantic Coast, Africa and South America. 
 
 An immature female, Katharine measured 14-feet, 2-inches. She was named for Katharine Lee Bates, the Cape Cod songwriter who wrote "America the Beautiful," and her transmitter emits a signal when her dorsal fin breaks the water's surface. 
 
 Katherine passed New Smyrna Beach on Friday and approached Canaveral National Seashore by nightfall. 
 
 After cruising off Cape Canaveral this weekend, Katharine continued southward. Detected at 12:38 p.m. Sunday roughly 20 miles offshore from Cape Canaveral, she pinged again at 7:27 a.m. Monday, 20-plus miles offshore from Sebastian Inlet. 
 
 Then she struck for the inlet — pinging at 5:01 p.m. Monday about 4,000 feet offshore from Sebastian Inlet State Park. 
 
 From there, Katharine swam Tuesday to Port St. Lucie, her southernmost destination since she was tagged. Total distance traveled since that date: 3,686 miles. 
 
 Though spinner, blacktip and bull sharks are more-familiar species along the Space Coast, Katharine's appearance is not unusual, said George Burgess, director of the Florida Program for Shark Research at the University of Florida. 
 
 Between January and May, Burgess said, the carnivores pursue North Atlantic right whales as they migrate off the coasts of northeast Florida and southern Georgia. 
 
 "Not coincidentally, white sharks will happily munch on a sick or slow whale — or even better, a calf. They're along to move the Darwinian evolution forward," he said. 
 
 OCEARCH founder Chris Fischer labeled Katharine "a good pinger" who may yield significant scientific data in the coming months. 
 
 "She's in her prime. She's probably in her late teens, early 20s. We don't know whether she's sexually mature or not. It'll be really interesting to see if Katharine returns to Cape Cod later this summer. If she does, then she probably didn't get pregnant. If she does not return to Cape Cod by July, then she's likely pregnant," Fischer said. 
 
 Katharine's Twitter account is maintained by a member of OCEARCH's social media team. Recent first-person tweets included a reference to the SyFy movie "Sharknado," self-depreciating jokes about her weight, and directives to #ReplaceFearWithFacts. 
 
 Despite their ferocious man-eating reputation, no confirmed great white attacks on humans have occurred in Florida waters. Sharks kill about five people a year worldwide, Burgess said. 
 
 Neale also reports for Florida Today 
 
 Read or Share this story: http://usat.ly/1lqVLF7 ||||| Image copyright OCEARCH / ROBERT SNOW Image caption Lydia was satellite-tagged off the coast of Florida last year, allowing scientists to track her movements 
 
 The first great white shark seen to cross from one side of the Atlantic to the other may be pregnant, says the head of the expedition tracking her. 
 
 At the weekend, the satellite-tagged fish, called Lydia, crossed the Mid-Atlantic Ridge, which marks a rough boundary line between east and west. 
 
 She has now turned towards the UK, but it is unclear where she will go next. 
 
 Chris Fischer told the BBC he thought she was pregnant and heading for birthing grounds in the Mediterranean. 
 
 Mr Fischer, who is expedition leader and founding chairman of the Ocearch shark tagging venture, said that if Lydia continued on to Europe or Africa, she was likely to become "more coastal". 
 
 If we're going to look after some of these magnificent apex predators - the lions of the oceans - we're all going to have to work together. No one country can do it Chris Fischer, Founding chairman, Ocearch 
 
 He told BBC News: "I certainly think that it's possible for Lydia to make it to the UK." But he said that he could not know if that was where she was heading. 
 
 Mr Fischer said there had been sightings of great white sharks in UK waters before, but added: "I think these were anecdotal versus a documented presence. So hopefully we'll be able to help with that." 
 
 On Sunday (GMT) , Ocearch announced that Lydia had crossed the ridge into the eastern Atlantic. And although it is often argued that the waters of these isles are too cold for the sharks, Mr Fischer cast doubt on this. 
 
 "One thing we have learnt just in the last year with sharks in the Atlantic is what we used to think was too cold simply is not," he said. 
 
 "Lydia has come over from Nova Scotia [in eastern Canada]... These sharks have the capacity to deal with very cold water temperatures for long periods." 
 
 But he said: "If I had to guess, I would guess that Lydia is pregnant, and that she has been out in the open ocean gestating her babies, and that this spring she will lead us to where those baby white sharks are born - the nursery." 
 
 Mr Fischer, who has led numerous ocean expeditions, added: "If you forced me to guess where that was, I'd say it was over in the Mediterranean, near Turkey... but that's longball I'm playing. She could turn around right now and head back to Florida." 
 
 Image copyright OCEARCH / ROBERT SNOW Image caption Chris Fischer described Lydia as "super-healthy" and reproductively mature 
 
 He said that small white sharks had been observed in the Aegean Sea before, but scientists working on the team did not share his view. This was because preliminary analysis of blood samples from Lydia suggested she was not pregnant at the time of her tagging. 
 
 But Mr Fischer defended his theory, saying there were still uncertainties over the way that white sharks become pregnant, adding: "The sperm from the male comes in a packet with a shell on it. They can carry it around for a while until a special organ inside them breaks down the shell and they get pregnant. 
 
 "We know it's 18 months from when we discover the breeding aggregation to when they lead us to the nursery... What we don't know is how long do they carry that sperm packet and how long is it until their body breaks down the shell." 
 
 Media playback is unsupported on your device Media caption Marine biologist Dr Gregory Skomal tells 5 live: "We're as surprised as anyone" 
 
 Lydia is now roughly 1,600km (1,000 miles) from the western coasts of Ireland and Britain, and nearly 4,800km from Jacksonville, Florida, where the tracking device was attached to her in March last year. 
 
 The young female shark has travelled more than 30,500km since last year. 
 
 The Ocearch project was initiated to gather data on the movements, biology and health of sharks for conservation purposes as well as for public safety and education. 
 
 The scientists have been using a custom-built 34,000kg (75,000lb) capacity hydraulic platform, operated from their research vessel the M/V Ocearch, to safely lift mature sharks so that researchers can tag and study them. 
 
 Image copyright OCEARCH Image caption Rizzilient's satellite tag now shows a location on land, in northern Portugal 
 
 Lydia was on the platform for 15 minutes, during which researchers extracted blood for analysis and performed an ultrasound examination, in addition to attaching the tag. 
 
 Mr Fischer described Lydia as "super-healthy" at the time of her tagging. "I would say she's just been sexually mature for a short period of time, which would put her in her 20s," he said. 
 
 "She looked like she had a bright future ahead of her - but I never would have dreamed she would lead us over to your neighbourhood. 
 
 "It just shows that if we're going to look after some of these magnificent apex predators - the lions of the oceans - we're all going to have to work together. No one country can do it." 
 
 Indeed, the threats currently facing shark species were illustrated when one of Ocearch's tagged animals - a 5ft-long female mako shark called Rizzilient - was apparently caught by commercial fishermen. The most recent fix for Rizzilient's satellite tag shows her on land, in the coastal city of Povoa de Varzim in northern Portugal. 
 
 Millions of sharks die each year as by-catch or through targeted hunting to remove their fins, which are highly prized in parts of Asia for use in shark fin soup and as traditional cures. 
 
 The Ocearch project has now tagged nearly 150 sharks, including not just great whites, but mako, hammerhead, tiger sharks and other species. Mr Fischer said one of the project's aims was to move away from the often competitive nature of academic research where data is proprietary. 
 
 "One of the things we wanted to do [with Ocearch] is disrupt the whole way research like this normally works," he said. 
 
 "The data is totally open-source, this is multi-institution and multidiscipline." 
 
 He added: "The great thing about this is that the whole world gets to watch... people feel inspired when they're part of something." 
 
 Paul.Rincon-INTERNET@bbc.co.uk and follow me on Twitter ||||| Is Lydia the great white shark PREGNANT? Tagged fish may be looking for a 'nursery' in the Mediterranean 
 
 
 
 On Friday, Lydia was spotted 1,000 miles from Cornwall and Ireland 
 
 The satellite-tagged 15ft, 2,000lb great white is around 800 miles away after she crossed the Mid-Atlantic ridge found in the middle of the ocean 
 
 Today GPS tag showed she is heading west, but experts think the shark is looking for a nursery in the Mediterranean where she can raise some pups 
 
 Great white sharks typically give birth to between two and 12 pups 
 
 
 
 Lydia became the first tagged great white to cross the Mid-Atlantic Ridge 
 
 
 
 No one understands why she is taking such a strange route as great whites are usually found in warmer waters 
 
 
 
 A great white shark heading for British waters could be bringing some smaller ferocious fish with her, scientists have revealed. 
 
 The deadly predator – named Lydia – became the first tagged great white shark to cross the Mid-Atlantic Ridge and scientists charting her progress have now revealed that the 15ft shark might be swimming towards Europe to give birth to pups. 
 
 She is just 800 miles (1,255km) off the coast of Cornwall and Ireland in the Atlantic Ocean and has now turned away from the UK. 
 
 Scroll down for video 
 
 The great white sharked named Lydia has travelled 313 miles in the past 72 hours. She is currently headed west (pictured) But experts believe the shark is pregnant and in search of a nursery for her pups and could be en route to the Mediterranean 
 
 HOW DO SHARKS GIVE BIRTH? 
 
 Very little is known about the reproduction of great white sharks. 
 
 Great white sharks are thought to reach sexual maturity aged around 15. The oldest female ever recorded was 40 years old. 
 
 The predators are ovoviviparous which means that eggs develop and hatch in the uterus and continue to develop until birth. 
 
 The great white shark has an 11 month gestation period and the pups' jaws start to form at one month. 
 
 Unborn sharks feed on ova produced by the mother and are born in spring and summer. 
 
 Mother sharks typically give birth to between two and 12 pups. 
 
 But experts think she may be aiming for Turkey in search of a nursery in the long-run. 
 
 Lydia, who weighs 2,000lb (907kg) has covered more than 19,400 miles in the past year since being fitted with a tracking device. 
 
 She is being tracked as part of a ground-breaking marine life study by Osearch that aims to learn more about sharks' movements. 
 
 Scientists have been following the ferocious fish for over a year and her progress can be followed on the project’s website. 
 
 ‘Lydia pinged in this morning headed NW!’ researchers tweeted this morning. 
 
 Experts say they are shocked by Lydia’s recent dash towards Europe and she has travelled 313 miles in the past 72 hours. 
 
 Chris Fischer, expedition leader and founding chairman of the Ocearch shark tagging project, said Lydia may be looking for somewhere to rear young. 
 
 He said: ‘I would guess that Lydia is pregnant and that she has been out in the open ocean gestating her babies and that this spring she will lead us to where those baby white sharks are born - the nursery.’ 
 
 He thinks her chosen location may end up being off the coast of Turkey. 
 
 
 
 Record breaker: The deadly predator has become the first tagged shark of its species to cross the Mid Atlantic Ridge, an enormous underwater mountain range under the ocean. She is currently swimming to the west (pictured) 
 
 Deadly cargo: Tagging the shark (pictured) was a feat in itself, with heavy machinery used to hoist Lydia from the water in order to fit the tracking device 
 
 WHAT IS THE MID-ATLANTIC RIDGE? The Mid-Atlantic Ridge (MAR) is a ridge found along the floor of the Atlantic Ocean. 
 
 This rift marks the actual boundary between adjacent tectonic plates, where magma from the mantle reaches the seafloor, erupting as lava and producing new crustal material for the plates. 
 
 It forms part of the longest mountain range in the world and separates the Eurasian Plate and North American Plate in the North Atlantic, and the African Plate from the South American Plate in the South Atlantic. 
 
 Great White Sharks normally give birth to between two and 12 pups at a time after a gestation period of 11 months. 
 
 
 
 Blood samples didn't show Lydia was pregnant when researchers used a 34,000kg hydraulic platform to hoist her from the water to fit her tracking device. 
 
 
 
 But Mr Fischer, who has led numerous ocean expeditions, said there is uncertainty over how exactly Great Whites reproduce. 
 
 
 
 ‘The sperm from the male comes in a packet with a shell on it. They [the female sharks] can carry it around for a while until a special organ inside them breaks down the shell and they get pregnant. 
 
 
 
 ‘We know its 18 months from when we discover the breeding aggregation to when they lead us to the nursery. 
 
 
 
 ‘What we don't know is how long they carry that sperm packet and how long is it until their body breaks down the shell.’ 
 
 Lydia had been heading north but made a sharp turn back towards the U.S. 
 
 
 
 Ladbrokes bookkeepers revealed odds of 2-1 for Lydia visiting Cornwall as her first port of call. 
 
 Lydia has become the first tagged great white to cross the Mid Atlantic Ridge (pictured) - an underwater mountain range which separates the Eurasian and North American Plates - at around 10am on March 9 
 
 Her GPS tag only gives off a signal when she's near the water's surface so scientists sometimes have to wait days between new readings. 
 
 
 
 Mr Fischer said it was impossible to predict where she'll head next. 
 
 
 
 He said: ‘If you forced me to guess where that was, I'd say it was over in the Mediterranean, near Turkey - but that's long-ball I'm playing. 
 
 
 
 ‘She could turn around right now and head back to Florida.’ 
 
 She became the first tagged great white to cross the Mid-Atlantic Ridge - an underwater mountain range which separates the Eurasian and North American tectonic plates - on the morning of March 9. 
 
 
 
 Great whites are traditionally tracked off the coasts of South Africa, Australia, New Zealand, the west coast of America from California up to Alaska, the Gulf coast and Hawaii. 
 
 
 
 Shark biologist Ian Fergusson tweeted: ‘WhiteShark Lydia pinged in on the other side of MidAtlanticRidge! Welcome to the history books, #Lydia,’ while Chris Fischer, who is involved in the project, tweeted: '#Lydia turns E toward #UK continuing first doc Trans/Atl migration n hist!’ 
 
 
 
 Lydia was tagged by the Ocearch project, which aims to monitor sharks to learn more about their movements 
 
 Dr Gregory Skomal, 52, senior fisheries biologist with Massachusetts Marine Fisheries, said: ‘I have no idea what to expect from her next. I've been working with sharks for a very long time now and I have never seen anything like this.' 
 
 ‘It's anyone's guess where she is going to go next but she has been heading east so she might continue to do so.’ 
 
 
 
 ‘She's just short of 800 miles away from your coast now but in the grand scheme of things that really isn't far for her. It's all very exciting. 
 
 
 
 ‘It's hard to say how long it might take her to get there. If she decides she wants to get to England she could get there in days. 
 
 
 
 ‘Having said that, she is quite likely to meander. It could take her days, it could take her months, or it might not happen at all. 
 
 
 
 ‘I think it would be great to see her turn up in the UK though.’ 
 
 
 
 Though Lydia's journey is impressive, great whites are known for their marathon migrations. 
 
 In 2003 a great white nicknamed Nicole travelled from South Africa to Australia and back - some 12,400 miles. 
 
 In recent years there have been several sightings of Great whites off the coast of Britain. 
 
 In September last year, fisherman David Bond said he had spotted a 14ft beast swimming close to his boat off the coast of Looe in southern Cornwall. 
 
 The suspected sighting came just a day after a fisherman on board a lobster boat said he spotted a 'giant shark' get close to his vessel. 
 
 All those who witnessed the shark dismissed the idea it could be a basking shark, saying the creature was much larger, prompting experts to consider the possibility it was a great white.
– She is arguably the most famous shark in America, but Mary Lee has gone silent. After being tagged with a transmitter by research organization Ocearch back in 2012 off the coast of Cape Cod, Mary Lee gained a legion of loyal followers tracking her ocean journeys. (She has nearly 130,000 Twitter followers.) However, no ping has been registered since June, reports the Post and Courier of Charleston, SC. The good news is that this doesn't necessarily mean the end of Mary Lee: Chris Fischer of Ocearch tells Jacksonville.com that it's more likely the batteries in her transmitter, designed to last about five years, have finally given out. Fischer hopes to see Mary Lee again, but is OK if that never happens. “I feel like she’s done so much, it’s hard to ask for anything else,” he says. “For any individual shark, she’s undone more of the damage from Jaws than any shark in history, and she’s the most famous shark in history.” Mary Lee was 40 or 50 years old when first tagged, so Fischer figures she has another 20 years of life. Meanwhile, boaters and fishermen are being asked to keep an eye out, particularly off the coast of South Carolina. The 16-foot shark just happens to have a distinctive bite mark in her dorsal fin, raising hopes that if she is still swimming around out there, somebody will spot her.