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Are They Bad Guys or Just Misunderstood?

Sometimes reputation is not reality. Greater Cleveland Aquarium’s Education team takes a quick looks at snakes, piranhas and sharks to see if they’re really “bad guys” or just misunderstood.

SNAKES

Snakes have been portrayed as bad guys across the globe for centuries. Ancient Greeks share the myth of Medusa with her head of snakes turning humans to stone.  Christianity writes about snakes representing evil and temptation in the garden of Eden. Ancient Egyptians tell of a two-headed serpent guarding the underworld.
Paired with the fact that some snakes deliver a venomous bite, it is not surprising that many people dislike or even fear snakes. However, with more than 3,000 different species of snakes on the planet, there is much to celebrate as well. Less than 7% of snake species are able to significantly harm a human. Snakes play an important role in keeping rodent pest populations under control. Many snakes are both predator and prey in an ecosystem food web, so losing them would have a negative affect on many other species.

The snake at the Aquarium is a green tree python. She spends a significant amount of time curled up on her branch, basking in the humid, tropical temperatures. She starts her life as a different color entirely and becomes a brilliant green color as an adult.

If you encounter a snake, you should give them space, but there is no reason to harm it.

PIRANHAS 

The piranha’s negative reputation can be traced back to Theodore Roosevelt. He witnessed a staged feeding frenzy of starved piranhas on a trip to South America and wrote about the experience. More than 120 years later, these fish are still working against that tale. The 1978 movie Piranha showcasing a piranha hunting humans refueled the hype, as it showcased piranha hunting humans.

In reality, humans are not part of a piranha’s food chain. Many piranha feed on smaller fish species, and some are omnivores, eating both meat and plant material. In the scientific community, they are described as timid scavengers. Piranha group together for safety to protect themselves from their own predators, like large birds.

The piranha at the Aquarium are red-bellied piranha. They can be admired for their shiny scales. They are an important part of their ecosystems in freshwater rivers of South America. Piranha should be more appreciated than feared.

SHARKS 

Sharks are often portrayed as villains in movies. Jaws, Sharknado, The Shallows, The Meg and even The Little Mermaid portray sharks in a negative light. While some sharks are large, and some do have sharp teeth, there is way more to appreciate about sharks than to fear.

Sharks are apex predators. At the top of the food chain, they play a crucial role in keeping the ocean ecosystems in balance, but humans are not part of the menu. There are more than 400 species of sharks and they eat a variety of different types of foods, with the largest whale sharks eating krill, and the smallest dwarf lantern catching tiny prey with an alluring bioluminescent light.

The sharks at the Aquarium are sandtiger, sandbar and nurse sharks. A fan favorite of Aquarium guests, it can be quite calming to watch them swim slowly through the water.

You are more likely to be struck by lightning, fall off a cliff taking a selfie, or be killed by a lawnmower, than be attacked by a shark. Sharks should be revered rather than feared.

–Education 

Flipping the Script to Save Sharks

Think about spiders, piranhas, or snakes. Simply the sound of some animals’ names causes fear and panic. Whether it stems from tall tales or a few chance encounters, unfortunately for the animals involved, bad reputations developed over time tend to stick. Sharks might be the ultimate example of this situation. There have been many movies about sharks made over the years. A recent study from the University of Australia asserted that “almost all of these films (96%) overtly portrayed shark-human interactions as being potentially threatening to humans.” How factual and accurate have these movies been to sharks? Let’s take a closer look at a few of them.

In Jaws, Amity Island was terrorized by a Great White shark that ruined quite a few people’s vacations and the blockbuster film’s protagonists indeed ended up needing a bigger boat to catch this predator. Jaws had such an impact on our collective psyche that the reputations of Great Whites and other shark species remain affected by the movie to this day—46 years after the motion picture came out. The big myth in Jaws is that sharks specifically target humans. In truth, we simply are not on a shark’s menu. Rarely do humans and sharks come in contact, but IF they do, sharks mistaking a person for a seal or another one of their actual prey items might take an exploratory bite before quickly realizing the mistake and swimming off. A vengeful, human-seeking shark like the Great White in Jaws doesn’t occur in our oceans.

Many shark movies since Jaws have leaned into a more fictional sci-fi component, such as Deep Blue Sea, The Meg and, of course, all the Sharknado films. (They apparently made six so far?!). I hope I don’t need to let you know that no one needs to fear long extinct predators, DNA-altered sharks or waterspouts causing sharks to attack humans in the sky and on land.

But there are some movies that could seem very realistic to the average movie fan, such as The Shallows. This film finds an injured young surfer fighting for her survival in the open water while the Great White shark that bit her circles and zeroes in on its compromised target. Similarly, to Jaws, this movie portrays the shark to be following a prolonged plan of attack on our species, although on a smaller scale. Sharks don’t spend extended periods of time playing this cat-and-mouse game with prey. Many sharks like the Great White must be swimming constantly to breathe, and sharks are too smart to waste time and energy for very long before moving on to the next area or potential meal.

It’s important to know that we are not telling you to never watch another shark movie ever again. I love all kinds of movies and I know these thrillers can be fun to sit down and enjoy. We just ask to do your best in not letting television and movies fully form your opinion of animals like sharks. As apex predators, sharks are extremely important to the health of the oceans on which humans rely heavily. It’s vital that we are constantly trying to improve the public opinion of sharks for their overall conservation. A third of all shark species are threatened or endangered, and movies have done their part in contributing to the decline. Going forward, we need to try and continue to flip the narrative on sharks, talking about them in a positive way and focusing on the facts to protect them as a species and ultimately protect our oceans.

-Matt D., Education Coordinator

Shark Conservation: 4 Ways You Can Help

Sharks are some of the oldest and most complex organisms in the world and their absence would likely have a huge impact on the ocean ecosystem and our world as we know it.  Today, more than 11,000 sharks are killed by humans per hour due to bycatch, finning and overfishing. With humans killing an estimated 100 million sharks a year, it’s critical that we work to protect them. Here are a few ways you can actively support shark conservation.

Education

One of the best first steps to helping our oceans and animals is to educate ourselves! Research organizations all over the world collect data and information about our effect on the environment. Evaluating their findings leads to discussions and discoveries of ways that we can make a better and more conscious impact on the world.  Sharks4Kids goal is to create a new generation of shark advocates through curriculum, games, and activities that can be accessed on their website.  Some other great places we can learn from include:

Charities/Research Organizations

Supporting local and global organizations making a difference is important too. Support can be in the form of monetary donations that allow scientists to fund research vital to understanding the environment.  It can also be in the form of advocating and sharing the knowledge we get from these organizations with others.  The Shark Research Institute in Princeton, NJ conducts some of the most well-known shark research in the world. With one of the largest collections of data on these animals, the Institute is able to provide credible information to the media and help deter misconceptions about sharks.  Their efforts to help change the image of sharks is revered worldwide. Some other great places to look into include:

Reducing Single-Use Plastic

Reduce, reuse, recycle—one of the best known conservation slogans of all time is still an important and effective way to help cut down on pollution that directly affects sharks. Reducing our reliance on single-use plastic can yield amazing results.  By reducing plastic usage less trash accumulates in the ocean and less sharks and their natural food sources such as sea lions and sea turtles will consume these items.  When we refrain from polluting our waters we can in turn make them cleaner and there will be less of a chance for sharks to  consume plastic which can be harmful.  Ocean 4 Plastic is an organization with a mission to remove plastic from oceans.  Their two largest projects located in Haiti and Bali guarantee one pound of trash removal per $20 donation.  Their website features a live count of how many pounds of trash have been removed from oceans by their projects.  They also host cleanups worldwide and build recycling infrastructure in certain locations. Some other great places that actively do this include:

Shopping Sustainably

Being mindful about where you shop for and what foods you buy can have a greater impact than you might think. For example, the shark fin trade and production of shark fin soup greatly depletes shark populations worldwide. Choosing to shop in places that don’t support or contribute to these issues can help our shark populations grow. The Animal Welfare Institute provides a map showing what restaurants in the United States currently produce shark fin soup.  They implore individuals to call those places and ask them to stop providing any products containing shark fins. Want to know more about the impact of your purchase? Check out:

And, if you want a more hands-on experience, come into the Greater Cleveland Aquarium to learn more about our sharks and why it’s so important that we keep them around!

– Kloby R.

More Dangerous than Sharks

Did you know that the Florida Museum of Natural History documents all known shark attacks? They started the ISAF (International Shark Attack File) back in 1958. If we use the data collected to average fatalities from sharks over the last 60 years, the number is only 7 per year worldwide. If you put that into odds, it is 1 in 3,700,000. Now let’s compare that with the odds of dying from the flu, which is 1 in 63.

Turns out there are lot of things more dangerous than sharks, but we don’t seem to be afraid of them. So let’s take a look at what SHOULD scare us more than sharks.

How about bugs? Those annoying mosquitos are responsible for 800,000 deaths a year. Fire ants account for another 50 people and bees will kill 100 people in the U.S. alone. Those are large numbers for being such small animals.

There are plenty of other animals more dangerous to humans than sharks. Take, for example, the noble steed. Yup, horses kill about 20 people in the U.S. per year. Then there’s the loyal dog. (What can be better than a lick in the face from our beloved friend?) Turns out, dogs are responsible for 25,000 human deaths annually worldwide. And how about Bambi? Such a cute little creature, but deer are the reason 130 people die each year in the U.S. It seems cars and deer do not like each other very much.

So let’s focus on the automobile. There are more than 1.2 million traffic-related deaths every year. Traffic lights will be part of that with 2,000 deaths in the U.S. alone. People just ignore those lights but that could be because we’re all wrapped up in our online worlds. Cell phones should be far more feared than our finned-friends since 6,000 deaths in the U.S. are attributed to texting and driving.

Now that you have considered how dangerous the roads can be, perhaps you will decide to start walking more. Be forewarned—almost 6,000 people die every year from trips and falls. And if that (or any of these statistics) make you want to never leave your home, just remember that on average 450 people in the U.S. die from falling out of that bed, 26 people are crushed by sofas, and 30 folks are done in by falling televisions.

Hey, get outside already, go cut the lawn it is excessively high, but then you may be thinking about the 75 people in the U.S. that die from lawnmower accidents or the 24,000 people that die from lightning strikes every year. (Are those clouds over there?) Oh well, all this is making me hungry. Let us go wash up and go have some dinner, but watch out for the hot water. In the U.S., scalding tap water will kill 100 people this year. And oh, by the way, food—the very thing that keeps us alive—holds potential dangers. The World Health Organization estimates that about 420,000 people die yearly from contaminated food. (Five thousand of those are from contaminated raw meat within the U.S. alone.) Another 3,000 people a year die from choking and the National Institutes of Health has calculated that obesity is killing almost 300,000 people a year. And if you eat out often, take care when you sign your restaurant check because believe it or not, ballpoint pen caps are responsible for taking out 100 people per year.

So now that you are totally stressed out by these statistics, take a walk on the beach and try not to trip. However, watch out for the falling coconuts since they will add 150 people a year to that list of fatalities.

Let us celebrate being alive and safe from those sharks, but watch the champagne corks during that celebration so you do not add to the approximate 25 people per year that are killed by those projectiles!

– Matthew Ballish

Baby Shark! Shark Reproduction Continued

Shark reproduction is pretty strange to begin with. But for sand tiger sharks, it is even weirder.

Sand tigers are the largest sharks you’ll see at the Greater Cleveland Aquarium. Their mating behavior is pretty ferocious.

We don’t know what prompts female sand tigers to be ready to mate. They must be mature enough in age—somewhere in their teens—and the females must also be ready to mate, which happens about every two years. We are not sure how (or if) females select mates. Scientists are still studying this!

When sand tigers mate, the much smaller males must bite and forcibly flip over the much larger and thicker-skinned females.

But before the sharks get to that point, there is a period of courtship behavior—sort of like shark dating.

Males might follow a female, swimming behind and slightly below her in the water. Then he might escalate to tailing, during which he very closely follows her. The next step is nosing. The male will follow the female very closely, with his nose, or rostrum, very close to her cloaca. (The cloaca is a shark’s reproductive canal and its way to poop. Both males and females have a cloaca.) Then the male will nudge the female, then bite her fins or body—all the while hoping to bite her and flip her over to mate.

If the male is successful, he will bite the female on the pectoral (arm-position) fin and try to flip her over. She then will become catatonic and will allow mating.

But, if the female is not interested at any point, she may bite the male right back! And remember, the females are much larger and thicker-skinned than the males. Female sand tigers can also circle close to the bottom to prevent males from approaching her to bite.

If the female is interested in mating, she may point her nose downward and allow the male a better chance to bite her.

Then the male sand tiger can hold the female’s cloaca with his clasper. Claspers are two finger-like appendages that all male sharks, skates, and rays have behind their pelvic fins. The male can then deliver his sperm, cloaca to cloaca before swimming away.

The female can store the male’s sperm for an unknown amount of time—perhaps a year, perhaps more—until it seems a good time to carry pups.

Now things get even stranger.

The female sand tiger has two uteruses. So sand tigers can carry two totally separate pregnancies.

Since sand tigers are ovoviviparous, they lay eggs internally and then give live birth. But for sand tigers, life starts under difficult circumstances. Around 20 eggs may be fertilized in each uterus. Then the eggs develop into shark embryos. The embryos grow bigger and consume all the nutrition in their individual eggs.

Then the biggest, strongest sand tiger pup in each uterus eats all of its siblings. Intrauterine cannibalism! That is what scientists call it.

The surviving sand tiger pup eats whatever new eggs keep arriving in the uterus until it is ready to be born.

After eight or nine months’ gestation, the pup is born. It will be more than three feet long and totally independent immediately.

Scientists are still learning about sand tiger shark reproduction. At the Greater Cleveland Aquarium we have seen mating behavior, but no pups yet.

– Nora Morrison

Baby Shark! Shark Reproduction

In the Shark Gallery seatube, we often hear guests singing “Baby Shark” and sometimes we are asked how baby sharks are born. The answer to that is really fascinating.

There are around 500 species of sharks that we know of, and sharks are extremely varied in their size, body shape and how they reproduce.

All baby sharks begin when a male shark and a female shark mate. How sharks find each other, how they select mates and why they decide to mate is still something scientists are investigating.  The male normally bites the female to hold onto her and flip her over, and then uses his fingerlike appendage, called clasper, to deliver sperm.  Since female sharks are generally bigger than male sharks, this can be difficult for males.

The female shark can store the male’s sperm until the time is right to fertilize the eggs–sometimes even waiting for years! Then things get even stranger.

Baby sharks, which are known as pups, can be born in three quite different ways.

First, some sharks lay eggs. We call this oviparous. The “mommy shark” lays an egg case in a good spot and swims away. The egg case, which is sometimes called a mermaid’s purse,” can be perfectly camouflaged to blend in with the sea floor or algae. The egg includes all of the nutrition the pup will need to grow from a fertilized embryo to a fully functioning shark pup. When the pup is ready, it emerges from the egg case and is totally independent.

Second, some sharks grow from eggs–but inside the mother shark’s body. This is called ovoviviparous. In this type of reproduction, there is no placenta to link the “mommy shark” and the “baby shark.” The shark pup gets all of its nutrition from its own egg yolk, other egg yolks, or (yikes!) from eating its fellow fertilized eggs or other pups. Ovoviviparous sharks give live birth to a fully independent pup. This is how sand tiger sharks, like the ones you can see at the Greater Cleveland Aquarium, reproduce.

And third, some sharks do have a placenta and directly support the shark embryo until it is ready to be born as a pup. This is called viviparous, and is also how humans are born. When the shark pup has matured enough, it is born and swims away. This is how sandbar sharks, which you can also see at the Aquarium, have pups.

All sharks are born ready to fend for themselves! As soon as they’re born, shark pups are ready to swim, hunt and grow.

-Nora Morrison