sand tiger shark
Sand tiger sharks are also known as sand tigers and gray nurse sharks. Like all sharks, they breathe underwater, through their gills. But sand tigers have one unique habit. They are the only sharks that come to the surface to gulp air, but not to breathe. The air ends up in its stomach. The air makes the shark more buoyant, so it can float motionless in the water as it watches for prey.
Sand tigers generally hunt at night; just above the ocean floor. Sand tiger sharks like the shallow water close to shore and so have "sand" in their name. The "tiger" was inspired by their big appetite. Sand tiger sharks look ferocious, with a row of jagged teeth that you can see even when their mouths are closed! However, these fish are not very aggressive toward people and bother people only when people bother them first. Many aquariums keep sand tiger sharks in their shark exhibits because they're so impressive looking and survive well in captivity.
Some kinds of sharks lay eggs; others, like the sand tiger, give birth to live young called pups. A newborn can swim and eat right away. When young their main danger is bigger sharks, but once they grow to their full size, they no longer have major predators to worry about.
11 facts about the sand tiger shark | mental floss
If youve ever been to a major aquarium, theres a good chance you've been face to fin with a sand tiger shark. Heres everything you should know about this wicked-lookingbut pretty mild-mannered creature.
The sand tiger shark (Carcharias taurus) isn't related to the tiger shark (Galeocerdo cuvier), but it does have something in common with another popular speciesthe great white (Carcharodon carcharias). They're both Lamniformes, an order of sharks that share a signature look: five pairs of gill slits, two dorsal fins without spines, a relatively big mouth, and a lack of nictitating membranes, the protective, see-through shields over the eyes that many other sharks possess. Other Lamniformes are the basking shark, the goblin shark, and the prehistoric megalodon shark. True tiger sharks dont make the cut; theyre part of a different order known as the Carcharhiniformes.
Look at a sand tiger and the first thing youll notice will probably be its long, outward-pointing teeth, which remain visible even when the sharks mouth is closed. Curved, slender, and serration-free, the teeth are perfect for puncturing the skins of small to mid-sized fish: slippery animals that can be hard to grab onto. This is in marked contrast to both the can-opener-shaped teeth we see in real tiger sharks and the thick slicing teeth of big-game hunters like great whites.
By swallowing mouthfuls of air at the oceans surface, sand tigers can turn their stomachs into air pockets. Doing so helps the fish keep a neutral buoyancy level under the surface, enabling them to hover around motionlessly. (When it descends, the animal releases air bubbles out of its mouth.) No other shark exhibits this air-gulping behavior.
Sand tigers tend to shy away from people, but they have been known to steal fish from spear- and net-hunters. That can bring them into conflict with humans, and when the sharks feel threatened, they may bite back in self-defense.
Still, according to the International Shark Attack File (ISAF), a global database maintained by the Florida Museum of Natural History, sand tigers have only been implicated in 29 unprovoked attacks on human beings since 1580. None of those attacks were fatal.
Full-grown sand tigers are around 10 feet long and can weigh over 400 pounds. For decades, their intimidating size made the sharks prized trophies amongst recreational fishermen. From June to September 1918, 1900 sharksprimarily sand tigerswere caught in the area of Nantucket Sound. They continue to be hunted in some corners of the world for their meat, skin, teeth, and fins.
Because sand tigers tend to mate near shorelines, it's easy to net large numbers of them during the breeding season. Scientists estimate that the population living along the U.S. eastern seaboard shrank by 70 to 90 percent in the late 20th century due to overzealous commercial fishermen. A slow reproductive rate further handicaps the species, as does coastal pollution in the estuaries where their young tend to reside.
The International Union for Conservation of Nature (IUCN) lists the sand tiger shark as vulnerablethe ranking given to creatures that are at risk of becoming endangered. Sand tigers now enjoy protected status in Australia and the United States.
This is another name which doesnt make evolutionary sense because the species isnt related to actual nurse sharks. Sand tigers have also been referred to as spotted ragged tooth sharks because adults and juveniles occasionally come with reddish-brown spots on their backsides.
Not all of them will be born, thoughin fact, the majority wont. About five months into a nearly year-long gestation, a few of the eggs will begin to hatch and swim around the uterus. And they're hungry. To survive, the biggest fetuses devour unhatched eggs and smaller, weaker siblings who have already hatched out. When the mother finally gives birth, only two shark pups will remainone for each uterus.
By shark standards, newborn sand tigers are exceptionally large, stretching up to 3 feet long apiece. At that size, the juvenile sharks have an easy time fighting off many would-be predators after they're born. Bulking up on their siblings beforehand might be a secret of survival.
The practice might also be a matter of sexual selection: Female sand tigers tend to mate with several different partners each breeding season, and it's been hypothesized that the eggs from the first encounter will be the earliest to fertilize. As a consequence, theyll grow faster and be more likely to gobble up all the rival fetuses sired by other males. So in theory, a female sand tiger could choose to mate with her preferred partner first, giving his unborn offspring the best chance of survival.
To get away from adults who might attack them, pups (a.k.a. juvenile sharks) often spend a few months out of every year in shark nurseries: shallow, relatively secluded parts of the ocean where full-grown sharks are less common than they might be elsewhere. In 2016, researchers identified Great South Bay, a watery divide between Long Island and Fire Island, as a sand tiger nursery. It was discovered after a catch-and-release program noticed that young sand tigers whod been fitted with tags were coming back to the same lagoon summer after summer. Other verified sand tiger nurseries include Massachusettss Plymouth and Duxbury Bays.
Tiger sharks and great whites are ill-suited for captivity, but sand tigers do wellgiven the right setup and proper care, sand tigers can live for decades in aquariums. One female named Bertha lived at the New York Aquarium in Coney Island for over 40 years before dying in 2008. (Attempts to breed sand tigers in captivity seldom work out, but some facilities like the now defunct Manly Sea Life Sanctuary in Australia had some success.)
To keep them in mixed-species tanks, staff members do their best to ensure that the sharks are well-fed at all times. At the Tennessee Aquarium, for example, the resident sand tigers are fed three times every week, with each individual receiving enough food per session to equate to around 2 percent of its body weight. This strategy discourages captive sharks from trying to eat live tankmatesalthough they may still nibble on the other fish every so often.
North Carolinas outer banks are home to more than 2000 documented shipwrecks, earning it the nickname Graveyard of the Atlantic. Smaller fish are liable to transform ship remains into faux reefs, unwittingly attracting predatory sand tigers, who like to hunt on the sea floor. In the Graveyard of the Atlantic, divers have reported seeing over 100 sand tigers around a single wreck.
In 1915, American ichthyologist Russell J. Coles was monitoring fish off of Cape Lookout in North Carolina when he saw a gang of at least 100 sand tigers surround a school of bluefish. Working together, the sharks drove their victims into very shallow waters and then attacked them. On another occasion, a group of sand tigers near New South Wales started flailing their tails about like bullwhips, producing cracking noises that the sharks used to corral some yellowtail kingfish into a tight, vulnerable clusterjust in time for lunch.
gigantic shark washes up on the shore in north carolina | the daily caller
According to a Facebook post from the Topsail Online Gazette, a sand tiger shark was on the shore, and the evidence might keep you out of the water forever. (SLIDESHOW: These Women On Instagram Hate Wearing Clothes)
sand tiger shark | national geographic
Sand tiger sharks, also known as gray nurse sharks, have a deceivingly ferocious look. They are large-bodied and display a mouthful of sharp teeth that protrude in all directions, even when the mouth is shut. Despite this, they are a docile, non-aggressive species, known to attack humans only when bothered first.
Sand tiger sharks are brownish-gray with rust-colored spots on top and white underneath. They have a flattened, cone-shaped snout and a distinctive, oblong tail with a notched, upper lobe that is significantly longer than the lobe below. Individuals range in size from 6.5 to 10.5 feet in length.
Their name comes from their tendency toward shoreline habitats, and they are often seen trolling the ocean floor in the surf zone, very close to shore. They are found in warm or temperate waters throughout the world's oceans, except the eastern Pacific.
Sand tigers are the only shark known to come to the surface and gulp air. They store the air in their stomachs, which allows them to float motionless in the water, seeking prey. They are voracious predators, feeding at night and generally staying close to the bottom. Their staple is small fish, but they will eat crustaceans and squid as well. They occasionally hunt in groups, and have even been known to attack full fishing nets.
Although this species is widespread and is not widely fished for food, it has one of the lowest reproduction rates of all sharks and is susceptible to even minimal population pressure. For this reason, it is listed as vulnerable and is protected in much of its range.