5 Things I Learned About Ripsaw Catfish

February 26, 2025

5 Things I Learned

Primarily found in waterways throughout the Amazon, you’re looking at the ripsaw catfish. Here are 5 things a non-aquarist learned about this fascinating animal at Greater Cleveland Aquarium.

This species’ genus name—Oxydoras—means sharp skin. With serrated scales and thorn-like hooks for defense along its sides, it’s easy to see how this armored catfish earned the name “ripsaw.”
Interestingly, these catfish reside in both whitewater and blackwater rivers. Whitewater rivers have higher amounts of suspended sediment and low acidity, while blackwater rivers are slow moving, transparent and more acidic.
Also called the “talking catfish,” ripsaws make audible grunts and clicks to communicate.
Like other catfish, a ripsaw’s whiskers are actually sensory organs known as barbels! These organs allow the fish to locate food including larvae, crustaceans and insects.
You may also notice the ripsaw catfish’s downward-facing mouth. This allows it to scoop food from the riverbottom where it combs for its meals.

With a distinct appearance and relatively large size, it’s hard not to notice the ripsaw catfish. Look for one during your next Greater Cleveland Aquarium visit.

5 Things I Learned About Picasso Triggerfish

December 12, 2024

Written by Greater Cleveland Aquarium

Known for its bright, distinctive bands of color reminiscent of a Pablo Picasso painting, you’re looking at the aptly named Picasso triggerfish. Here are 5 things a non-aquarist learned about this fascinating species at Greater Cleveland Aquarium.

1: Some know this species by a different name: lagoon triggerfish. Another fitting title for a fish that spends most of its time
in sub-tidal reef flats and shallow lagoons.

2: For breeding, this species forms distinct pairs. Females build the nest before laying eggs and become very territorial as they guard their future young.

3: Because of the shape of the dorsal and anal fins, this species can swim forwards, backwards and even hover in place.

4: When alarmed, the triggerfish makes a whirring sound. Researchers believe the whirring warns other triggerfish of potential danger.

5: The “trigger” in triggerfish comes from their dorsal spine, which can be raised when startled. If the fish is hiding in a small space, the spine acts as a wedge to hold them in place.

With its bright coloration and attention-grabbing name, it’s hard not to notice the Picasso triggerfish. Look for one during your next Greater Cleveland Aquarium visit.

5 Things I Learned About Northern Clingfish

Written by Greater Cleveland Aquarium

This flat, round animal is the Northern clingfish, typically found in in the Eastern Pacific from Alaska to Mexico. Here are 5 things a non-aquarist learned about this fascinating species at Greater Cleveland Aquarium.

1: With a slightly flat, depressed head, the clingfish’s pelvic fins connect to form an adhesive disk, which it uses to stick itself strongly to rocks and plants. Just to hammer home how impressive their physiology is, scientists are currently in the process of creating suction cups inspired by the northern clingfish’s disk.

2: Clingfish use their suction to steady themselves as they pull prey off rocks. Their favorite menu items include crustaceans and mollusks.

3: In terms of their predators, clingfish have to keep an eye out for snakes, gulls and even raccoons, who might snatch them up at low tide!

4: Northern clingfish reproduce by laying eggs under rocks. The eggs hatch into what are called platonic larvae and it’s the males who protect the babies.

5: A northern clingfish can survive low tide by breathing air—well, more like it absorbs oxygen through its skin, which is a useful trait for an intertidal fish.

Look for this interesting fish clinging to the glass or rocks of its habitat during your next Greater Cleveland Aquarium Visit. Nature. It’s a curious thing.

5 Things I Learned About the Brownbanded Bamboo Shark

July 11, 2024

Written by Greater Cleveland Aquarium

Found around coral reefs and sandy, muddy-floored habitats, brownbanded bamboo sharks are a smaller species coming in at only 2.8 feet long on average. Here are 5 things a non-aquarist learned about this fascinating animal at Greater Cleveland Aquarium.

Brownbanded bamboo sharks change color as they mature—juveniles maintain a medium-brownish color with dark banding, while adults appear solid brown. They’re estimated to live around 25 years.
These sharks dine on smaller fare, like crabs, small fish, shrimp and bristle worms. Their own predators include larger fish and even other sharks.
Brownbanded bamboo sharks are largely nocturnal, spending most of the daytime hiding in small spaces in the reef. After dark, they come out to hunt.
Brownbanded bamboo sharks lay eggs in elongated cases. Given their smaller stature, it’s no surprise newborns are only 5 – 7 inches long when they hatch.
Surprisingly, this species of shark can tolerate hypoxia—low oxygen levels—for up to 12 hours. This adaptation helps them survive low tides in the shallow pools where they’re often observed. Could you hold your breath that long?

Look for this interesting shark, as well as—sandtigers, sandbars and Atlantic nurse sharks—during Fin Fest (Now – Tuesday, August 6) at Greater Cleveland Aquarium. Nature. It’s a curious thing.

5 Things I Learned about the Sandbar Shark

June 24, 2024

Written by Greater Cleveland Aquarium

Sandbar sharks, like the one you see here, reside within shallow coastal waters around the globe—ranging from Massachusetts all the way to Brazil in the Western Atlantic. Here are 5 things a non-aquarist learned about this interesting animal at Greater Cleveland Aquarium.

1. This species of shark is considered an opportunistic bottom feeder. From small fish and crustaceans to octopi and stingrays, sandbar sharks don’t leave much off the menu.

2. The only predator of sandbar sharks are—can you guess?—other sharks! Juveniles will sometimes fall prey to larger species like bull sharks, otherwise there are few animals interested in hunting them.

3. Sandbar sharks only breed every 2-3 years and live anywhere from 25 – 30 years old. Researchers estimate full maturity happens around 13 – 16 years of age, meaning they reach true adulthood around the time you first learned to drive!

4. In 2020, the International Union for Conservation of Nature classified sandbar sharks as endangered, citing a 50 – 80% decrease in population over the last 75 years. However, management plans have been put in place and those regions are seeing populations begin to stabilize in the shallow waters they call home.

5. Sandbar sharks migrate seasonally, with juveniles often moving from shallow coastal waters to warm deep waters. Interestingly, males tend to migrate in large schools, while females make the journey solitarily with no company.

Look for sandbar, sandtiger and other species of sharks during your next Greater Cleveland Aquarium visit. Nature. It’s a curious thing.

Best Places to Dive: Cave of Elephants – Crete, Greece

June 8, 2023

Diving

Written by Greater Cleveland Aquarium

In 1999, a daring spearfisherman in Greece named Manolis Efthymakis made a stunning discovery. While free-diving 30 feet down, he saw an opening in the cliff wall and did what most of us would not: he swam into it. What he found drew the interest of both the diving and the archaeological community.

Tens of thousands of years ago, the waters of the Mediterranean were low enough that animals walked into this cave, leaving behind fossils of a previously unknown species of elephant as well as a dwarf deer only 30 centimeters tall, or roughly three apples high. (A Smurf deer!) While many of the elephant bones, named Elephas chaniensis after the nearby city of Chania, were removed to museums, some things were left behind to attract divers to this cavern wonder.

The underwater entrance leads to a 100-foot-long tunnel large enough for divers to swim side by side until they reach a cavern filled with red-colored stalagmites and stalactites. Pitch black except for flashlights, divers then tread water to take in the views and pose for photographs while being careful not to kick one of the stalagmites growing beneath their fins. The swim back through the tunnel is notable for the eerie blue glow of the triangular opening back into the Mediterranean Sea.

I had the opportunity to explore this site in 2018 on a family trip to Greece. It followed what was initially a disappointing dive. The northwest corner of Crete, the largest of the Greek islands, is a rocky and arid environment. The town closest to the dive site, Kokkino Chorio to the south, was used in the filming of Zorba the Greek. Our first dive was totally devoid of any life except for a small silver fish we helped free from an old fishing net. The second dive into the cave was incredibly memorable and has been noted as one of the best cave dives in the world, although that is somewhat misleading as there are breathable air pockets within the cave, you’re always within site of the entrance, and there is no sediment to kick up on the bottom that might obscure vision underwater. It’s perhaps more accurate to call it a cavern dive.

Although we did not see any other signs of life on our dive, the waters around Crete and the Cave of Elephants itself is often a refuge for the Mediterranean Monk Seal (Monachus monachus) which is a critically endangered species of seal with fewer than 600 surviving members around the world.

Cave of Elephants is the fifth in our weekly series of the Aquarium dive team’s favorite dive locations. Stay tuned for the rest of our list or suggest somewhere new we might want to explore.

Ray D.

Best Places to Dive: Cenote Dos Ojos, Quintana Roo, Mexico

May 25, 2023

Diving

Written by Greater Cleveland Aquarium

A shade over 66 million years ago, a six-mile-wide meteor came screaming out of the heavens at 12 miles per second and a 60-degree angle to the surface of the Earth, which is kind of a worst-case scenario angle in terms of plunging chunks of space rock. It absolutely pulverized the impact zone with the force of a 100 million megaton bomb, creating tsunamis hundreds of feet high and flinging rocks half a continent away. For non-avian dinosaurs, the impact marked the end of an era. Literally. This is where the Mesozoic Era ended, and the Cenozoic began—the infamous K-T Extinction that eliminated roughly 80 percent of all species on the planet.

We know this hurtling chunk of death as the Chicxulub Meteor, named after the Mexican town at the center of its crater, which lies at the northern end of the Yucatan Peninsula along the Gulf of Mexico. The dinosaurs may have nothing to recommend the Chicxulub Meteor, but humans have reaped the benefits; the Cenozoic kicked off the “Age of Mammals” where Homo sapiens flourished.

The Yucatan Peninsula, that large thrust of land that sticks out northeast from Central America and divides the Gulf of Mexico from the Caribbean Sea, has a truly unique geology. It is a flat slab of limestone with 1,000 miles of shoreline that is completely devoid of surface water. There are no rivers, bridges or lakes in northern Yucatan. Instead, brittle limestone cracks and fissures drain rainwater from the surface into a vast underground river system that stretches for hundreds of miles.

Cenotes, or sinkholes, dot the surface and provide access to the underground waterways. The ancient Mayan civilization relied on cenotes for potable water and regarded them as sacred wells, building cities, like Chichen Itza, around these gateways to the underworld and placing offerings to the gods in them, occasionally in the form of human sacrifices.

Two of our staff divers, Matthew Ballish and Stephanie Quinn, have journeyed to the popular Dos Ojos Cenote to explore what lies beneath. Dos Ojos, from the Spanish “Two Eyes,” is north of Tulum in the state of Quintana Roo and refers to a pair of cenotes (blue eye and black eye) that connect into a large cavern below. Snorkelers can swim in the crystal-clear water at the surface, while scuba divers follow two lines (known as the “Barbie Line” and the “Bat Cave”) through pitch black tunnels studded with stalagmites and stalactites.

Matthew, who has been the Greater Cleveland Aquarium Assistant Dive Safety Coordinator for eight years and has more than 600 dives in his 36 years of experience, was drawn to Dos Ojos because of its proximity to the cities along the Riviera Maya, allowing him easy access while on vacation to a great dive spot. Though there are more than 6,000 cenotes across the Yucatan Peninsula, Stephanie and her husband found that the wealth of information available about Dos Ojos and the easy access made it an ideal spot to explore these ancient gateways.

Formal exploration of Dos Ojos began recently in 1987, and in 2018 an access point was found to the much larger Sistema Sac Actum, making the entire system the longest underwater cave system in the world.

Free of particulate matter as the rainwater filters through the limestone, the waters of the cenotes are amazingly clear and their temperature stays a constant 77° F year-round. The depth isn’t more than 33 feet in the cavern, and though there are few fish, divers will find signs of life at the aptly named “Bat Cave.”

“Underwater, you’ll see pieces of fruit tossed aside by the bats,” Matthew remembers. “When you surface to look at the bats above your head, you’ll be happy you have a mask on . . . the odor is powerful.”

Cenote Dos Ojos is the third in our weekly series of the Aquarium dive team’s favorite dive locations. Stay tuned for the rest of our list or suggest somewhere new we might want to explore.

–Ray D.

Best Places to Dive: Neptune Memorial Reef, Key Biscayne, Miami, Florida

May 15, 2023

Diving

Written by Greater Cleveland Aquarium

When Greater Cleveland Aquarium Diver Damon Johnson swam with his first eagle ray in the Atlantic Ocean a few years ago, it was at one of the more unusual dive sites in the world. Neptune Memorial Reef, which will be the largest man-made reef in the ocean once it’s completed, offers people an opportunity to mix the cremated remains of their loved ones into the cement structures that make up the reef.

Just over three miles off the Atlantic Coast of Key Biscayne (south of Miami, Florida), and 40 feet underwater, plans for Neptune Memorial Reef show it eventually covering 16 acres of ocean floor and including more than 250,000 memorials to both humans and their beloved pets. It already has at least one famous resident—celebrity chef Julia Child.

Although far from finished, the reef is already transforming the underwater environment. The bases, pillars and arches are engineered to support marine life in all its forms. Coral and other benthic animals grow on the texture of the base and pillars, and the arches have holes where prey animals can hide from predators. A recent survey showed hundreds of species including bluehead wrasse, sergeant majors, barracudas and pufferfishes. Crabs, lobsters and sea urchins can be found in the crevices and of course, as Damon and his father discovered, divers might even find a majestic eagle ray, which can have a wingspan up to ten feet. The bevy of life swimming amongst the cremated remains is perhaps perfectly summarized by Neptune’s motto “creating life, after life.”

Damon has been diving since 2019. His father got certified soon after and they found that they enjoyed diving the warm, turquoise South Florida waters together. He and his father are now both certified advanced divers and look forward to diving Dubai in the near future.

Neptune Memorial Reef is the second in our weekly series of the Aquarium dive team’s favorite dive locations. Stay tuned for the rest of our list or suggest somewhere new we might want to explore.

-Ray D.

Best Places to Dive: Forfar Field Station, Andros Island, Bahamas

May 5, 2023

Diving

Written by Greater Cleveland Aquarium

We dive for a variety of reasons. To commune with nature, to unwind, to explore. Our “pale blue dot,” as astrophysicist and author Carl Sagan pointed out, is just a “very small stage in a vast cosmic arena,” but perhaps by diving in we can learn to better appreciate that fragile ecosystem largely invisible to us as we commute between school, work and the grocery store in our busy daily lives.

Greater Cleveland Aquarium diver Stephanie Quinn took a formal approach to learning about our dot when she enrolled in a study abroad program during her senior year at Ohio University. Stephanie and her future husband spent a week at the Forfar Field Station, an educational and scientific non-profit organization that has served as a resource to over 50,000 thousand students ranging from middle school to graduate students and researchers. Most field study trips last a week and involve groups of 10-45 students with a focus on marine science, geology, botany, climate change or other scientific fields including social science. Imagine a classroom along the shoreline where students put their learning to the test by plunging into their environment.

“Forfar Field Station is a rustic former dive resort nestled in a beachfront coconut grove on the east coast of Andros Island,” according to their website. The largest of the Bahamian islands, Andros is host to rich diving opportunities for the students, including “coral reefs, offshore cays, sea grass beds, sandbars, blue holes, subtropical terrestrial habitats, Bahamian settlements and more.” The waters nearby are filled with colorful reef fish, including blue tang, angelfish, parrotfish and butterflyfish.

“It was the best diving,” Stephanie recalls. “Crystal clear water. Great biodiversity. We dove both there (Forfar Field Station) and Small Hope Bay during our study abroad. We then went back to Small Hope Bay for our honeymoon.”

Stephanie joined the Aquarium’s dive team in 2015 and has been a certified diver for 22 years. She lost her logbook, but estimates she has roughly 75 dives outside of the Aquarium. According to Aquarium Assistant Dive Safety Coordinator Matthew Ballish, she has more than 1350 dives in the habitats here.

Sagan, in his well-known speech, said that astronomy was a humbling experience. “To me,” he said, “it underscores our responsibility…to preserve and cherish the pale blue dot, the only home we’ve ever known.” These words were meant for the study of the stars but could apply just as well to those that look under the sea.

Forfar Field Station is the first in our weekly series of the Aquarium dive team’s favorite dive locations. Stay tuned for the rest of our list or share your favorite place to dive with us.

– Ray D.