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Shark Spotlight: Nurse Sharks

It’s that time of year again! Fin Fest is only a few weeks away, and we can’t wait to welcome shark lovers of all ages to the Aquarium to celebrate with us. Sharks are already on our minds 24/7, but Fin Fest gives us an excuse to really show how much we appreciate these jaw-some animals.

This week we’re covering the nurse shark, the sedentary bottom-dweller that can be found hanging around the lower, more secluded areas of the shark gallery. There are a few theories on how nurse sharks got their unusual common name. Most agree that it comes from the old English word “hurse,” meaning “seafloor shark,” but others argue the name was inspired by the sound they make while hunting which is often compared to a nursing baby.

The unique noise comes from their feeding technique, which involves sucking their prey up from the seafloor like a vacuum. Their mouths are just big enough to eat things that live near the bottom, like snails, crustaceans and mollusks, but too small to hunt for larger fish like their fellow sharks do. Being nocturnal hunters, they’ll begin to prowl the seafloor for food at night using the the whisker-like barbels that extend from their face to feel around for things to eat. “Here in Ohio, we think ‘Oh, that looks like a catfish,’” says aquarist Ray Popik of the nurse shark’s appearance, “and they actually do fill a bit of the same ecological niche.”

According to Popik, all of these characteristics go hand-in-hand. “During the daytime you’ll see them underneath ledges and in crevices hiding out. Then at night they’ll cruise the bottom scavenging for food,” he says. “Typically the more bottom-oriented the shark is, the more nocturnal it is. The opposite is true for sharks that are more active hunters, and nurse sharks are usually scavengers in the wild.”

Contrary to the popular belief that all sharks have to remain constantly swimming in order to breathe, nurse sharks and their seafloor-inhabiting peers can push water over their gills themselves without having to move much. They can circulate water through their systems by opening and closing their mouths, which allows them to stay put. The nurse shark’s bottom-dwelling habits usually catch the eye of Aquarium guests, as their behavior differs from the constant cruising of their “gallery mates” the sandtiger and sandbar sharks. However, Popik says their behavior is relatively common for seafloor shark species. “[Their behavior] is unique out of our three species,” he explains, “but it’s not terribly unique in the wild.”

Hanging out in the lower regions of their exhibit, the calm-and-collected nurse shark shows us how varied shark behavior can be in nature. Next week we’ll be talking about the sandbar shark, whose agile swimming and striking silhouette make it one of the most fun to watch animals here at the Aquarium — and don’t forget, Fin Fest is happening right here every day from July 22nd through the 29th. If you love sharks as much as we do, it’s the place to be, so don’t miss out.

Father’s Day Heroes: Seahorses vs. Seadragons

We’re gearing up for Father’s Day, which made me think about the many different kinds of “wild” dads there are here at the Aquarium. While they’re all deserving of our appreciation, none go above and beyond quite like seahorses and weedy seadragons. When these species reproduce, it’s the male who nurtures the developing embryos and carries them to term. In short, pregnant dads! Really makes you rethink gender roles, doesn’t it?

This unique reproductive method is exclusive to the family Syngnathidae, which also includes pipefish and pipehorses. Some other things all syngnathids have in common are fused jaws, the absence of pelvic fins and thick, bony armor covering their bodies — but male pregnancy, in terms of pure “wow” factor, is their main calling card as a group of species. The female deposits the unfertilized eggs with the male, who then cares for the growing embryos until they’re born. However, no two syngnathids share the exact same reproductive process. This includes our seahorses and seadragons, who differ in a couple of interesting ways.

First of all, the seadragon and the seahorse carry fertilized eggs in different locations. A pregnant seahorse looks pretty familiar to us humans, as they carry their young (who often number in the thousands, by the way) in a pouch located in their abdominal area. This gives them a sort of potbelly appearance. Seadragons, on the other hand, carry their eggs on a specialized patch of skin at the base of their tails.

The hatching processes of the two species are also completely different. Seahorses’ brood pouches begin to expand right before they give birth. This happens as the fully-grown seahorse embryos begin to hatch from their egg membranes and move freely around the pouch. Once the pouch is at capacity, the seahorse finally gives birth, releasing the entire brood at once in dramatic fashion.

Meanwhile, seadragons give birth to their brood more slowly over a period of several days. The baby seadragons hatch one by one rather than all at the same time, decreasing the competition for food by dispersing the brood over a larger area of ocean. You could say seadragon dads go the extra mile to set their kids up for survival in the wild, however, it doesn’t look as impressive in captivity.

If you want to see these amazing aquatic parents up close, come visit us at the Greater Cleveland Aquarium in the First Energy Powerhouse on the West Bank of the Flats. Bring your own dry-land dad on Father’s Day, June 17th, and he’ll get in free with the price of a general admission ticket — find out more here.





Putting it to the Test: Cuyahoga River’s Water Quality

Cuyahoga means “crooked river,” for good reason; it kind of looks like a backwards letter “U.” The river begins with two separate branches in Geauga County which join and flow south through the city of Akron.  The river then comes back north to Cleveland and empties out in Lake Erie.

Throughout the 1800s, Ohio grew. The Ohio and Erie Canal gave local businesses and farms access to resources. That connectivity meant Ohio’s farmers could sell their goods for higher prices in a more competitive market.

But as industry and population grew there were some consequences. The Cuyahoga River suffered. Minimal laws for waste regulation combined with chemical and steel materials dumped into the river – the Cuyahoga caught on fire not once or twice, but thirteen times. The most famous fire, in 1969, gained national attention and began an environmental movement that sparked initiatives such as the Clean Water Act of 1972 and the formation of the Environmental Protection Agency. The Cuyahoga began to clear.

Through its Rivers & Lakes: Keeping the Great Lakes and our Water Quality Scientist programs, the Aquarium brings students to the River’s banks to test its water quality the day of their visit. Using the scientific method, students determine if the water is excellent, good, fair or poor.

These tests take temperature as well as pH and nitrate levels into account. Students then discuss why it is important to test for these particular things and what variables can change the result. For example, oxygen levels can drop if the water is stagnant, phosphate levels will spike if farm fertilizer runoff enters the water and nitrate levels rise whenever human sewage is dumped in the river from sewer overflow points.  According to our Erin Bauer, Greater Cleveland Aquarium’s Education Coordinator, most days the Cuyahoga’s health comes out “fairly good,” but says there’s always room for improvement.

Students tend to have a range of reactions to being out by the river. Bauer states, “Getting to throw a water sample collection bucket into the river is always a highlight. Hearing kids make observations about what they see is always great. There are always a few ‘Eww, the brown water is nasty!’ and ‘Look at those plastic bottles out there.’  But there are also observations like ‘Cool! Look at those sea gulls!’ or ‘Wow, it’s bigger than I thought!’” Bauer is particularly happy when a barge passes by and the students can see how the river contributes to the region’s transportation needs.

The program has help from Northeast Ohio Regional Sewer District (NEORSD) which provides the tubes and tablets needed to test water quality.  They also gifted us an enviroscape model that illustrates waste water treatment, drinking water treatment, runoff in the watershed and combined sewers.

Facilitating connections between students and our natural resources is important and Bauer says, “NEORSD and the Aquarium share a desire to educate youth about the urban water cycle.”

Visiting students are asked to brainstorm ways they can make a positive environmental difference for the Cuyahoga River.  For example, buying organic produce can reduce phosphate levels, planting trees can decrease turbidity, and reducing water volume while showering or brushing teeth ultimately leads to a decrease in sewer overflow.

– Morgan Wright




How a President Propagated a Piranha Myth

Blockbuster thrillers like Jaws have given sharks an undeserved reputation as aggressive, man-eating killers. Similarly, stories about piranhas have portrayed this fairly calm species as bloodthirsty animals to be feared.

So where did this myth begin?

In 1913, Theodore Roosevelt made a trip to Brazil. To impress the adventurous former American President, locals took him deep into rainforest and allowed him to “discover” a river there but warned him not to venture in. What he did not know was that they had stocked the waters with unfed piranhas. To illustrate the dangers for the former President and accompanying journalists they threw a cow into water filled with starving piranhas. (Was it a dead cow? Bloody bits of diced meat? A sick cow? This detail seems to change from story to story.)  Within moments there was a massive feeding frenzy.

Roosevelt went on to record his amazement of these seemingly perfect killing machines in his travel memoirs, which the American population devoured and became weary of the species. In 1914’s “Through the Brazilian Wilderness”, Roosevelt noted the following:

They are the most ferocious fish in the world. Even the most formidable fish, the sharks or the barracudas, usually attack things smaller than themselves. But the piranhas habitually attack things much larger than themselves . . . the piranha is a short, deep-bodied fish, with a blunt face and a heavily undershot or projecting lower jaw which gapes widely. The razor-edged teeth are wedge-shaped like a shark’s, and the jaw muscles possess great power. The rabid, furious snaps drive the teeth through flesh and bone. The head with its short muzzle, staring malignant eyes, and gaping, cruelly armed jaws, is the embodiment of evil ferocity; and the actions of the fish exactly match its looks.”

Although not based on real-world circumstances, Roosevelt’s vivid account the experience has only gained momentum over the years. Once Hollywood latched onto the myth and created the 1987 film “Piranha,” the unfortunate characteristic stuck.

In truth, piranhas are relatively calm until spooked. This animal can be skittish, especially if there are a larger number of them in one exhibit. The Red-Bellied Piranha, native to South America, feed on fish, snails, insects and aquatic plants, only occasionally eating larger mammals and birds.

We caught up with Connor while he was feeding our red-bellied piranha and asked him for the real story behind these beautiful fish.

Curious to learn more? Check out:

– Morgan Wright

What Happens in Winter?

People who live here know it can get pretty cold in Northeast Ohio. Luckily, we can wrap up in a cozy scarf, pull on some lined gloves and add another layer of clothing when temps start to drop. Those animals that live in cold weather year-round have adaptive features to help them through the cold winter months. But what about the animals that don’t have an extra layer of blubber or plans to fly south . . . how do they survive a deep freeze?

Some Ohio animals, like groundhogs, hibernate. According to the Ohio Department of Natural Resources, groundhogs hole up much of the winter in a state where their body temperature lowers their heart rate slows significantly. When it gets really frigid other creatures such as skunks, raccoons and chipmunks will seek shelter to sleep a few days until things warm up.  Birds that don’t migrate might put on some weight and change their diets. But what happens to fish?

“Cold-blooded animals, such as fish, maintain body temperatures to that of their surroundings,” explains Greater Cleveland Aquarium curator Stephanie White. “Therefore fish move to the deepest, warmest spots within the water body during cold winter months.” Fish can enter torpor, which is shorter than a full hibernation. Torpor includes a body temperature reduction, slowed metabolism, slowed reaction times, a reduction in breathing rate and primary body functions. During the state of torpor, a fish will not actively seek prey, instead allowing food to come to them, saving their energy. With slowed activity and conserved energy, their dietary needs decrease in the winter.

And what about Fido in your backyard? How cold is too cold for our own domestic animals? While a specific answer cannot be determined across the board, consider your dog’s size, fur thickness and breed. Owners that have clothing for their animals are advised to not leave them unattended in case the sweater gets hooked on an object outdoors. PetMD suggests that once temperatures drop under 20°F, all owners should limit time outdoors and be aware that their animals could potentially develop cold-associated health problems like hypothermia.

Animals have their different adaptations to survive inclement weather, both warm and cold. Their bodies know what they can stand and will give signs of if they cannot. To learn more about our animals and their adaptations, don’t hesitate to ask any members of our curation team during your next visit!

– Morgan Wright, Marketing Assistant


5 Things I Learned about the Snowflake Eel

As we approach winter in Northeast Ohio my thoughts inevitably turn to the powdery white stuff we’ll be dealing with any day now. Maybe that’s why the Aquarium’s snowflake eels caught my interest. Here are five things I learned about these aquatic creatures:

This winter, visit the six snowflake eels at the Greater Cleveland Aquarium . . . where curiosity is natural

— Samantha Fryberger


How Every Day Can Be ‘America Recycles Day’

If you visit on November 15, you can join us in celebrating America Recycles Day! Although we’ll be highlighting the benefits of recycling on Wednesday, throughout the year we’ve been trying to reduce, reuse and recycle more.

Did you know that more than 8 million tons of plastic is dumped into our oceans every year? That’s not good for us or for our aquatic friends. Based on waste audits done by the Aquarium’s Green Team we estimate that by the end of this year we will have kept 2700 pounds of plastic out of landfills.

What can you do to minimize plastic and other non-biodegradable waste? First off, if you are not already recycling at home, then start. It’s not hard just go to your City’s website and find out what is accepted. (If you live in Cuyahoga County it is

Making recycling simple and convenient for your family makes it more likely they’ll participate. Try designating a bin in each living area that generates waste (kitchen, laundry room and bathroom). Then, label the containers with signs that list what is acceptable so no one puts an item that doesn’t belong.

Don’t think what you do matters? Here are some great facts about the benefits of recycling that illustrate just how much you can impact the environment by making small changes:

  • Recycling one ton of paper conserves 17 trees
  • Recycling just 48 cans is the energy equivalent of conserving one gallon of gas
  • Recycling plastic takes 88% less energy than making plastic from raw materials
  • Aluminum cans made from recycled aluminum use only 8 BTUs, which is a 95% energy savings

– Charlotte Cotter, Guest Experience Senior Lead

10-in-the-Bin America Recycles Day

Five Things I Learned from Fin Fest

It’s hard to believe our week-long celebration of sharks has come and gone. While admiring the five types of sharks we have here every single day is a large perk of working at the Greater Cleveland Aquarium, Fin Fest led me to a deeper appreciation of these animals. Even though the media often portrays them as a terrifying, there’s actually much more to revere than to fear when it comes to sharks. Here are a few Fin Fest facts that stuck in my mind:

  1. Humans kill an estimated 100 million sharks every year just for their fins.

While some sharks are allowed to be caught, illegal shark finning occurs when fisherman cut fins off live sharks and dump their bodies into the open ocean. The most popular use for the fins is shark fin soup, a delicacy in Chinese cuisine.

  1. More people die from carelessly taking selfies than from shark attacks.

From 2005 to 2014, an average of six people per year died globally from shark attacks. But more than 73 people worldwide are reported to have died while taking extreme photos of themselves in the first eight months of 2016 alone. So, not only is a death by Facebook vanity shot statistically more likely than death by shark, but you have better odds of being taken down by lightning or succumbing to the flu than being killed by a shark.

  1. Sharks have no bones.

Sharks have skeletons made of cartilage. When they die, saltwater can dissolve every part of their bodies except for their teeth.

  1. Not all sharks need to continuously move forward in order to breathe.

Many sharks swim constantly for buoyancy and to keep oxygen-rich water flowing over their gills. Others, like the nurse sharks in our main exhibit, are able to remain still and draw water into their mouths and over their gills.

  1. On average, sharks eat a bit less than 2% of their body weight.

In the wild, sharks would eat maybe once a week. At the Aquarium, we pole feed our sharks three times a week, ensuring they’re full (and uninterested in their exhibit cohabitants).


— Morgan Wright, Marketing Assistant

5 Boats You Can See From The River Hut

The Greater Cleveland Aquarium is just steps away from the Cuyahoga River. So, if you’re interested in bridges and boats, you have another reason to visit. On any given day you might see a freighter, cruise ship, barge, tugboat, pedal “brew boat,” or other water-worthy vessel pass by our Cleveland Clinic Children’s River Hut. And, if you need help with boat identification, we recommend

Here are five boats you can see from the banks of Cleveland’s crooked river:

Stephen B. Roman

The Stephen B. Roman is a freighter ship that transports dry cement from Canada. Named after Canadian mining engineer Stephen Boleslav Roman, it remains the last of Canada Steamship Lines’ original “Fort Class” of Great Lakes package freighters still in service.

Thomas R. Morrish

This tugboat from Michigan was built in 1980 under the name Lady Ora but has been through a series of names since. In 1999, Double Eagle Marine purchased and renamed the boat Island Eagle. White Near Coastal Towing acquired the boat in 2004 and renamed it Captain Zeke. And in 2014, Ryba Marine Construction purchased and renamed the boat Thomas R. Morrish.


The Buffalo is a self-unloading bulk freighter built in 1978. The Buffalo was built under Title XI of the Merchant Marine Act of 1970 which allowed U.S. shipping companies to construct new vessels or modernize their existing fleet through government funding and tax deferred benefits. The Buffalo was the seventh of ten ships launched for American Steamship under this program.

Herbert C. Jackson

In 1959, Great Lakes Engineering Works, River Rouge (Detroit), MI a new hull became the heaviest vessel ever side-launched by the shipyard. It was also second last ship built by the shipyard before it closed. Christened the Herbert C. Jackson for owners Interlake Steamship Co., it was part of a rescue of two boaters adrift on Lake Michigan.

Nautica Queen

nautica queen

Departing right next to the Aquarium, the Nautica Queen is a dining cruise ship. Passengers can enjoy an unlimited buffet meal, drinks, and musical entertainment while onboard. Plus, the Queen offers packages which include a discounted ticket to the Aquarium for a real underwater adventure!