11 Facts About the Sand Tiger Shark

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iStock

If you’ve ever been to a major aquarium, there’s a good chance you've been face to fin with a sand tiger shark. Here’s everything you should know about this wicked-looking—but pretty mild-mannered —creature.

1. IT BELONGS TO THE SAME ORDER OF SHARKS AS THE GREAT WHITE.

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 species—the 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 don’t make the cut; they’re part of a different order known as the Carcharhiniformes.

2. THOSE SCARY TEETH ARE LIKE DENTAL FISHING HOOKS.

Look at a sand tiger and the first thing you’ll notice will probably be its long, outward-pointing teeth, which remain visible even when the shark’s 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.

3. SAND TIGERS GULP AIR TO STAY BUOYANT.

By swallowing mouthfuls of air at the ocean’s 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.

4. VIOLENT ENCOUNTERS WITH HUMANS ARE RARE.

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.

5. OVERFISHING HAS HURT THE SPECIES.

Sand tigers might not pose much of a threat to us, but through sport and commercial fishing, we’ve done a number on them.

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 sharks—primarily sand tigers—were 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 “vulnerable”—the ranking given to creatures that are at risk of becoming endangered. Sand tigers now enjoy protected status in Australia and the United States.

6. IT’S CALLED THE “GREY NURSE SHARK” IN AUSTRALIA.

This is another name which doesn’t make evolutionary sense because the species isn’t 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.

7. EMBRYOS CANNIBALIZE EACH OTHER.

Male sharks have two fin extensions, called claspers, that they use to deliver sperm into a female sand tiger shark's two uteri, both of which are capable of hosting five to seven developing embryos.

Not all of them will be born, though—in fact, the majority won’t. 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 remain—one 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, they’ll 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.

8. LONG ISLAND HAS A SAND TIGER NURSERY.

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 who’d been fitted with tags were coming back to the same lagoon summer after summer. Other verified sand tiger nurseries include Massachusetts’s Plymouth and Duxbury Bays.

9. AQUARIUMS HAVE HAD A LOT OF SUCCESS WITH SAND TIGERS.

Tiger sharks and great whites are ill-suited for captivity, but sand tigers do well—given 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 tankmates—although they may still nibble on the other fish every so often.

10. THE SHARKS LIKE TO CREEP AROUND SHIPWRECKS.

North Carolina’s 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.

11. SAND TIGERS CAN HUNT COOPERATIVELY.

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 cluster—just in time for lunch.

8 Great Gifts for People Who Work From Home

World Market/Amazon
World Market/Amazon

A growing share of Americans work from home, and while that might seem blissful to some, it's not always easy to live, eat, and work in the same space. So, if you have co-workers and friends who are living the WFH lifestyle, here are some products that will make their life away from their cubicle a little easier.

1. Folding Book Stand; $7

Hatisan / Amazon

Useful for anyone who works with books or documents, this thick wire frame is strong enough for heavier textbooks or tablets. Best of all, it folds down flat, so they can slip it into their backpack or laptop case and take it out at the library or wherever they need it. The stand does double-duty in the kitchen as a cookbook holder, too.

Buy It: Amazon

2. Duraflame Electric Fireplace; $179

Duraflame / Amazon

Nothing says cozy like a fireplace, but not everyone is so blessed—or has the energy to keep a fire going during the work day. This Duraflame electric fireplace can help keep a workspace warm by providing up to 1000 square feet of comfortable heat, and has adjustable brightness and speed settings. They can even operate it without heat if they just crave the ambiance of an old-school gentleman's study (leather-top desk and shelves full of arcane books cost extra).

Buy It: Amazon

3. World Explorer Coffee Sampler; $32

UncommonGoods

Making sure they've got enough coffee to match their workload is a must, and if they're willing to experiment with their java a bit, the World Explorer’s Coffee Sampler allows them to make up to 32 cups using beans from all over the world. Inside the box are four bags with four different flavor profiles, like balanced, a light-medium roast with fruity notes; bold, a medium-dark roast with notes of cocoa; classic, which has notes of nuts; and fruity, coming in with notes of floral.

Buy it: UncommonGoods

4. Lavender and Lemon Beeswax Candle; $20

Amazon

People who work at home all day, especially in a smaller space, often struggle to "turn off" at the end of the day. One way to unwind and signal that work is done is to light a candle. Burning beeswax candles helps clean the air, and essential oils are a better health bet than artificial fragrances. Lavender is especially relaxing. (Just use caution around essential-oil-scented products and pets.)

Buy It: Amazon

5. HÄNS Swipe-Clean; $15

HÄNS / Amazon

If they're carting their laptop and phone from the coffee shop to meetings to the co-working space, the gadgets are going to get gross—fast. HÄNS Swipe is a dual-sided device that cleans on one side and polishes on the other, and it's a great solution for keeping germs at bay. It's also nicely portable, since there's nothing to spill. Plus, it's refillable, and the polishing cloth is washable and re-wrappable, making it a much more sustainable solution than individually wrapped wipes.

Buy It: Amazon

6. Laptop Side Table; $100

World Market

Sometimes they don't want to be stuck at a desk all day long. This industrial-chic side table can act as a laptop table, too, with room for a computer, coffee, notes, and more. It also works as a TV table—not that they would ever watch TV during work hours.

Buy It: World Market

7. Moleskine Classic Notebook; $17

Moleskin / Amazon

Plenty of people who work from home (well, plenty of people in general) find paper journals and planners essential, whether they're used for bullet journaling, time-blocking, or just writing good old-fashioned to-do lists. However they organize their lives, there's a journal out there that's perfect, but for starters it's hard to top a good Moleskin. These are available dotted (the bullet journal fave), plain, ruled, or squared, and in a variety of colors. (They can find other supply ideas for bullet journaling here.)

Buy It: Amazon

8. Nexstand Laptop Stand; $39

Nexstand / Amazon

For the person who works from home and is on the taller side, this portable laptop stand is a back-saver. It folds down flat so it can be tossed into the bag and taken to the coffee shop or co-working spot, where it often generates an admiring comment or three. It works best alongside a portable external keyboard and mouse.

Buy It: Amazon

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Treat Your Feline This Holiday Season With Fancy Feast’s Cat Food Advent Calendar

Fancy Feast/Chewy
Fancy Feast/Chewy

In anticipation of the holiday season, many children and adults get to unwrap mini presents each of the 24 days leading up to Christmas day, during what's known as Advent. Though Advent itself dates back to the 4th century, the version we know today, complete with the chocolate-filled calendars, was popularized in the early 1900s. And apparently it's no longer just for humans, because Fancy Feast is letting your feline roommate in on the fun with this unique cat food Advent calendar, now available at Chewy for $23.

For the 24 days leading up to Christmas, your cat will get to enjoy a variety of different wet foods, including favorites like grilled salmon, chicken, and more. There is even a unique ornament included with each calendar featuring a cat in the shape of a heart that can go right onto your tree. (Also, don't be surprised to find your actual cat making its way into the middle of your tree; they're known climbers.)

Now while you enjoy your Advent calendars from brands like LEGO, Funko, and more, your cat will be able to join in on the fun as well. To learn more about Fancy Feast's Feastivites Advent Calendar, head on over to Chewy.

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