11 Facts About the Sand Tiger Shark

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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.

How to Clean Your Dog's Ears (and How Often You Should Be Doing It)

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iStock/Group4 Studio

When it comes to keeping our dogs looking their best, we usually do all the normal pampering—giving them baths, cutting their nails, brushing their teeth, and grooming their fur. But one task that often gets overlooked is cleaning their ears.

Ear infections are a common ailment in dogs—particularly in breeds that have long, droopy ears (like cocker spaniels or basset hounds) or those that grow hair in their ear canals (as poodles do). A foul or yeasty odor in the ears is one quick way to tell if your pup might have an ear infection; redness and discharge, or frequent head-shaking or scratching, are some other signs that there might be an issue. If your dog seems to be in pain or cries when you touch around their ears, you'll want to schedule an appointment with your vet for as soon as possible.

Even if your dog doesn't seem prone to ear infections, it's important to keep their ears clean in order to keep it that way. According to Dogster, you should be cleaning your dog's ears anywhere from once a week to once a month, depending on the breed. Your vet can give you a recommendation for how often you should be cleaning your pup's ears, and even a quick lesson on how to do it yourself at home.

If you're uncomfortable undertaking the task on your own, your vet can do it for you—as can a dog groomer. But if you want to give it a try on your own, it's actually pretty simple. All you really need are some cotton balls and a vet-approved ear cleaner (your vet may sell one, or be able to tell you the nearest pet supply store or website that does).

According to Dogster, you should apply the dog cleaner to your dog's ear with a cotton ball or gauze. Squeeze a bit down the ear so that it makes its way into the ear canal, then gently massage the dog's ears near the base in order to break down any debris and/or ear wax. If your dog needs to shake their head, let them. Then, use the cotton ball or gauze to wipe the inside of the ear clean. (It may take a few swipes to clean the ear out fully.)

Though you may be tempted to use a cotton swab, just as with your own ears, this is a bad idea. "I generally don’t like to put Q-tips down the ears because I don’t like to push stuff down," Dr. Jeff Grognet, co-owner of Mid-Isle Veterinary Hospital in Qualicum Beach, BC, Canada, told Dogster. "This dilutes the ointment, but also, in some cases, the ointment doesn’t even get through to the skin inside the ear."

Cleaning your dog's ears is definitely easy, and important enough that there's no excuse not to make it a part of your regular grooming routine.

10 Fun Facts About Corgis

iStock/Lisa_Nagorskaya
iStock/Lisa_Nagorskaya

You already know they’re cute, compact, and smart. But there’s a lot more to these beloved little dogs that you might not know. 

1. THERE ARE TWO DISTINCT BREEDS OF CORGIS.

There are two types of Welsh corgis: the Pembroke Welsh corgi and the Cardigan Welsh corgi. They are considered two entirely different breeds because they come from different ancestors. Their remarkable resemblance is a result of crossbreeding in the 19th century.   

If you’re trying to tell the two breeds apart, the most notable difference is that the Pembroke does not have a tail. On top of a tail, Cardigan Welsh corgis also have rounded ears, while Pembrokes generally have pointy ears. 

2. THE CARDIGAN WELSH CORGI IS THE OLDER BREED.

Photo of a Welsh Corgi Cardigan
iStock/Silense

A warrior tribe of Celts brought the corgis in their aboriginal form to Cardiganshire, Wales around 1200 BCE, which means corgis have been in Wales for over 3000 years. This early breed was a member of the Teckel family of dogs that went on to include the dachshund. 

3. PEMBROKE WELSH CORGIS HAVE A CONSIDERABLE HISTORY AS WELL.

welsh Corgi Pembroke sitting in autumn leaves
iStock/HelenaQueen

Although no one knows for sure, most agree that the Pembroke Welsh corgi dates back to 1107 CE when Flemish weavers migrated to Wales. The Spitz-type dog bred with the original Cardigan corgis to produce the Pembroke Welsh corgis we know today. 

4. THE KENNEL CLUB ORIGINALLY LUMPED THE TWO BREEDS TOGETHER.

The two types of corgis were registered as one in 1925, leading to a lot of stress among breeders. Often a judge would favor one breed over the other, which would lead to controversies at dog shows. After nearly a decade of (pretty adorable) strife, the breeds gained separate recognition in 1934. 

5. CORGIS WERE ORIGINALLY USED AS HERDERS.


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The Welsh used the short dogs as herders as early as the 10th century. In those days, pastures were considered common land, so there were no fences. In order to keep a farmer’s cattle together and separated from other herds, corgis would nip at their legs to herd them. Because of their closeness to the ground, corgis had easy access to the cows’ ankles and were difficult targets of the retaliatory kicks of cattle. 

6. ACCORDING TO WELSH LEGEND, FAIRIES RIDE THEM.

Some say that the corgi is an “enchanted dog” favored by fairies and elves. At night the magical creatures would use the dogs to pull their carriages and be their steeds in battle. According to legend, the markings on a corgi’s coat suggest the faint outline of a saddle and harness. 

7. THE ROYAL FAMILY LOVES THE PEMBROKE WELSH CORGI.


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Queen Elizabeth II has had more than 30 corgis in her lifetime. Though her last two corgis—Whisper and Willow—have both recently passed away, she does still have two dorgis (corgi/dachshund mixes) named Candy and Vulcan.

The Queen met her first corgi when King George VI brought a male pooch home from a kennel in 1933. Named Dookie, the dog was an immediate hit with the future queen and her sister, Princess Margaret. 

After a second corgi named Jane entered the picture, the canine couple had a litter of puppies, two of which were kept. The Queen received another dog named Susan for her 18th birthday—from there, the collection of corgis really gained momentum. Some of the royal corgis bred with Princess Margaret’s dachshund Pipkin to create dorgis.

8. CORGIS WERE USED TO PREDICT PRINCESS CHARLOTTE'S NAME.

In the spring of 2015, when Prince William and Kate Middleton were awaiting the birth of their second child, people are already taking bets on the name. Gambling company Ladbrokes used corgis in an attempt to predict what the name would be. The company’s ad featured 10 corgis wearing vests with different names in a race to predict what the name of the child would be. The corgi sporting the name Alexandra won the race. Princess Charlotte was born on May 2, 2015.

9. CORGI MEANS "DWARF DOG" IN WELSH.

According to the Oxford English Dictionary, cor means dwarf and gi means dog.  

10. SOUTHERN CALIFORNIA HOSTS A ENORMOUS CORGI MEETUP.


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SoCal Corgi Beach Day started as a humble meet-up event at Huntington Beach in 2012. The first event attracted just 15 dogs; the last one had more than 1100 corgis in attendance. The event happens three times a year.

An earlier version of this article ran in 2015.

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