Endangered Species

July 25, 2016

What exactly does endangered mean? You often hear species described as “endangered” but what does that imply? When an animal is deemed “endangered”, it means that species is likely to become extinct if changes in the conservation strategy are not altered. The term endangered is one of many classifications on the Red List created by the International Union for Conservation of Nature (IUCN). This list is the world’s most comprehensive inventory of the global conservation status of thousands of biological species and is used to assess their extinction risk.

This figure shows the relationships of the different classifications of the IUCN Red List *EX-Extinct, EW-Extinct in the wild, CR- Critically endangered, EN- Endangered, VU-Vulnerable, NT- Not Threatened, LC-Least Concern

According to the 2015 Red List, 3,801 animals are listed as endangered. Species at higher risk are classified as critically endangered which is only one step below extinct in the wild. There are 2,542 animals in this critically endangered category. 5,639 animals are classified as vulnerable; this means that these species will likely become endangered unless the circumstances threatening their survival improve.

As you walk through the Greater Cleveland Aquarium you can spot some of these threatened species. In the Ohio Lakes and Rivers Gallery, you will find our spotted turtle (endangered) and shovelnose sturgeon (vulnerable). As you make your way through our ocean exhibit your eyes will be drawn up towards some of our largest residents, our sand tiger and sandbar sharks, both of which are classified as vulnerable.

There’s also another very important species in the exhibit: the critically endangered goliath grouper.

You’ll likely find this fish in the very front of the exhibit, often tucked between a few of our nurse sharks. This impressive fish can grow to be 8 feet in length and weigh up to 800 lbs. Naturally residing in shallow, tropical waters along the Atlantic coast this fish was often sought after by fishermen. Their fearless nature made them especially easy prey for spear fishermen. Unfortunately, due to their large size, slow growth and reproductive rate these fish are very susceptible to overfishing. This has led to severe population declines, classifying them as critically endangered.

Goliath groupers are now protected from harvest: if you catch one it must be released immediately. These sanctions set in place are beginning to positively impact the grouper populations. There are many other ways you can help threatened species like the goliath grouper:

Recycle! A lot of trash ends up in our lakes, rivers, and oceans. This is very bad for the organisms that call these places home. By keeping trash out of these areas, species will have a better environment to thrive in! (The GCA hosts beach cleanups throughout the year!)
Fish responsibly and support responsible fishing methods! Millions of tons of marine species are caught each year as bycatch. Sometimes this bycatch significantly outweighs the intentional catch. This poses a serious threat to many marine species including dolphins, whales, sharks, and turtles.
Actively support legislation to prevent overfishing. Many species are now threatened due to overfishing and irresponsible fishing methods. Help support regulations to protect marine species!

Find and Watch Dory, But Don’t Buy Her

July 15, 2016

Animal Care

Written by Greater Cleveland Aquarium

With the recent release of Finding Dory, marine life organizations want to remind families of being a proper pet ownership for fish.

In the movie Finding Dory, the main character is a Blue Tang. At the moment, Blue Tangs cannot be bred in captivity. What some marine life organizations fear is that Blue Tangs will be pulled out from the wild and attempted to be sold in pet stores. When that happens, collectors will double their efforts to obtain more blue tangs, and that will inevitably lead to their coral reefs habitats in the Coral Triangle being harmed. While blue tangs are sold as 1- to 2-inch animals, they reach 12 inches as adults and have difficult care requirements, making them unsuitable for most home aquarists.

Similarly, this happened with Clownfish with the release of Finding Nemo. After the release, sales skyrocketed for Clownfish. These fish are different from Blue Tangs in that they can be good for a beginner pet fish owner and can be bred in captivity. According to Variety, “By 2012, the orange and white stripped fish were the fifth-most imported species in the United States. In the process, wild populations of Clownfish in countries such as the Philippines were decimated.”

The positive from movies such as Finding Nemo and Finding Dory is the spike in interest from all different age ranges about marine life. The opportunity for education now presents itself about fish, aquarium keeping and other topics to discuss in the classroom and at home.

Disney developed educational materials for those who may look for more information regarding pet fish ownership, including recommendations that “Blue tangs, like Dory, do not make good pets so instead choose appropriate aquacultured fish.”

Sewage, Sludge, & Fire: Students Investigate Water Quality of the Cuyahoga River

May 10, 2016

Written by Greater Cleveland Aquarium

What comes to mind when you hear the words “Cuyahoga River”? If you said “gross,” “burning river,” or “industrial wasteland,” you are not alone. And, unfortunately, that is not too far from the truth. The Cuyahoga River has quite a colorful history with sewage, sludge, and fires, but, let’s start at the beginning.

THE BASICS

Map of the Cuyahoga River Watershed Photo credit: Wikipedia

Cuyahoga means “crooked river,” and it certainly earns the name; it kind of looks like a backwards letter “U.” The river’s origin starts in two separate branches in Geauga County which join and flow south through the city of Akron. The river then loops back north to the city of Cleveland making several tight hairpin turns at the end before emptying out into Lake Erie.

The Cuyahoga’s watershed, or drainage basin, consists of farmland, many urban and suburban neighborhoods, and some green space like Cuyahoga Valley National Park.

THE HISTORY LESSON

When Moses Cleveland first landed on the Cuyahoga in 1796, the river was beautiful and pristine. He surveyed the land around the river and deemed it a prime place to expand our country westward; and thus, the city of Cleveland was born.

Through the 1800s, Ohio’s growth became exponential. With the addition of the Ohio and Erie Canal, connecting Lake Erie to the Ohio River, local businesses and farms had access to fancy goods and building materials from factories along the east coast. Ohio’s farmers could sell their goods for higher prices in a more competitive market. Our city grew quickly and Cleveland became THE place to be.

By the 1900’s America was at the height of the industrial revolution. John D Rockefeller and Andrew Carnegie contributed significantly to the growth of Cleveland. Carnegie produced steel mills (steel is essential for building sky scrapers and large bridges) and Rockefeller produced oil refineries (kerosene lamps were used to light every home in the country). At this time, more millionaires lived in Cleveland than in New York City.

One of Rockefeller’s oil refineries. Photo credit: wikipedia

While businesses boomed, and Cleveland became richer, the Cuyahoga River suffered the consequences. With no laws in place to regulate waste, industries dumped all kinds of chemicals and waste materials into the river. Imagine open trenches in which gasoline slid from the oil refineries to the river (gasoline was an unwanted byproduct prior to the invention of cars). The pristine Cuyahoga landscape Moses Cleveland once surveyed had been replaced with buildings, concrete, and an immense amount of pollution.

Here comes the crazy part. There was so much sludge, gasoline, industrial waste, etc. entering the river that the Cuyahoga caught on fire! Not once, not twice, but thirteen times. The biggest fire, pictured below, occurred in the 1950s. The most famous fire, igniting in 1969, gained national attention and sparked an important environmental movement. Have you ever heard of Earth Day?

Photo credit: Ohiohistorycentral.org

Time Magazine published a famous article about the Cuyahoga, titled “America’s Sewage System and the Price of Optimism.” It describes the river at its worst using phrases like, “Chocolate-brown, oily, bubbling with surface gases, it oozes rather than flows,” and, “Anyone who falls in the Cuyahoga does not drown… He decays.”

Photo credit: Cleveland.com

Along with the Clean Water Act of 1972, and the formation of the Environmental Protection Agency (EPA), the general public started to increase their environmental literacy. Slowly but surely, over time, the river started to recuperate. Though we’ve amended some of the obvious pollution sources (no more open trenches of gasoline), we still have a long way to go to fully restore the river to a healthy state.

AT THE AQUARIUM

Students assemble a timeline of Cuyahoga History. Photo credit: GCA

In our Rivers & Lakes: Keeping the Great Lakes Great program, and our Water Quality Scientist program, we take kids to the Cuyahoga to determine the health of the river today. Guided by the scientific method, the students complete a set of scientific tests to determine whether the water quality is excellent, good, fair, or poor.

***Link Rivers & Lakes: Keeping the Great Lakes Great program to https://www.greaterclevelandaquarium.com/wp-content/uploads/2013/05/Rivers-Lakes-Keeping-the-Great-Lakes-Great-Teacher-Guide.pdf

***Link Water Quality Scientist to https://www.greaterclevelandaquarium.com/educate/fieldtrips/

Students test for temperature, pH, dissolved oxygen, phosphates, nitrates, and turbidity. We discuss why each of these parameters is important and what can make their levels change. For example: oxygen levels can drop if the water is stagnant, phosphate levels spike when farm fertilizer runoff enters the water, and nitrate levels rise when human sewage is dumped in the river from sewer overflow points. According to our research, most days the Cuyahoga’s health comes out “fairly good.” There is definitely still room for improvement.

Student teams test the water for dissolved oxygen content.

LOOKING FORWARD

We end our water quality programs with a discussion about the future. How can we restore the river to its excellent, healthy state? First and foremost, become environmentally aware and literate. Share the information you learn with your friends and family. Every action, from every person, contributes to our river’s health. We all have to do our part.

How can YOU help the Cuyahoga River? Here is a short list to get you started:

Stop littering and pick up trash you see along the river
Plant trees — trees and plants hold back sediment and reduce turbidity.
Turn off the water while you brush your teeth and take shorter showers – by conserving water, less wastewater will enter our rivers during heavy storm events through combined sewer overflow
Learn about Combined Sewer Overflow: https://vimeo.com/7707491

Buy organic produce — organic farms do not contribute to fertilizer runoff
Support local parks and help with river restoration projects
Reduce, reuse, and recycle
Continue Learning! Check the additional resources below.

Learn more about Cuyahoga River history and the many river fires:
http://www.pophistorydig.com/topics/cuyahoga-river-fires/

Learn more about watersheds and stormwater runoff:
http://www.neorsd.org/stormwater-watersheds.php

Read the 1969 Time Magazine article:
http://content.time.com/time/magazine/article/0,9171,901182,00.html

Learn more about education programs at Greater Cleveland Aquarium:
https://www.greaterclevelandaquarium.com/educate/fieldtrips/

Water Quality at the Aquarium

April 28, 2016

Animal Care

Written by Greater Cleveland Aquarium

Taking care of the animals at the Greater Cleveland Aquarium means taking care of their homes. Sometimes that means cleaning the décor, and sometimes it means taking care of the water itself…this is where water quality testing comes in. I do most of the water quality testing here at the aquarium. There are many interesting pieces of equipment (with fancy names) that go into testing, including a spectrophotometer, pH probe, refractometer, and titration kit.

Spectrophotometer

We test for a number of things at different times. Nitrogen is one of the most frequent tests. The nitrogen cycle includes ammonia, nitrite, and nitrate. Bacteria convert the toxic ammonia from fish wastes to less toxic nitrite, and then to the much less toxic nitrate. We test all of these regularly, adding reagents that will react to the nitrogen, and using the spectrophotometer, a machine that reads the color change and converts it to a measure of ammonia, nitrite, or nitrate.

Blank ammonia test, sample ammonia test, sample nitrite test

Two more very important tests are pH and salinity. Evaporation can change the salinity of the water as the salt gets left behind in the smaller volume of water. When adding water back, it is important to know how much fresh and how much salt water to add to keep the salinity in the narrow range that is best for the animals. These are tested with the pH probe and refractometer directly.

pH probe refractometer

Alkalinity is related to pH. It is a measure of the buffering capacity of the water; its ability to maintain a steady pH in the face of other changes. We measure this with a titration kit.

Alkalinity titration

Some animals have special needs, and their water gets additional tests. For example, elasmobranchs such as sharks and rays require iodine, so their water is tested for it. Corals and hard shelled invertebrates like snails require lots of calcium and magnesium to make their shells. These are tested ensure the water always has enough for them. These two tests also use titration methods.

A lot goes in to making sure our animals are healthy and happy. What many people don’t realize is that chemistry plays a large role here at the aquarium in addition to the manual labor and biology that takes place in every day operations. I am lucky enough to participate in these roles for work every day.

Pharyngeal Jaws and Green Moray Eels

April 20, 2016

Species Highlights

Written by Greater Cleveland Aquarium

Did you know that there are animals at the Greater Cleveland Aquarium that have more than one jaw? Moray eels have been known to have a second jaw, or pharyngeal jaw. The aquarium is home to several moray eels, many of which you can find in the Shark Exhibit swimming right along with the sharks and other fish.

Green moray eels are a pretty amazing animal, full of secrets. Just about ten years ago researchers discovered that these curious animals actually have a second jaw. This jaw, known as a pharyngeal jaw, is how they are able to eat. Most fish use suction to swallow. They expand their mouths to create negative pressure. This negative pressure causes water and prey to rush into their mouths allowing them to swallow their prey. Moray eels do not have this ability. Instead, they lie in wait in caves and crevices for their prey to swim by. They then burst out and grab their prey with their oral, or first set, of jaws. Their pharyngeal jaws then move forward to grip it. They can then move these jaws backwards to swallow their prey whole. They typically eat fish, shrimp, squid, crabs and octopus.

Another secret that green moray eels have is that they are actually brown! Their bodies are covered with thick yellow mucus that gives them their vibrant green color. This mucus protects the eels from parasites and infectious bacteria.

Green moray eels are found along the western Atlantic and into the Gulf of Mexico. They’re frequently found in the Bahamas and the Caribbean and been found as far south as Brazil. When full grown they can get to be 8 feet long and weigh as much as 65 pounds. Green moray eels have few natural predators once they reach full size, although smaller eels must look out for sharks and other large predators.

Next time you are at the aquarium make sure you look for the green moray eels. They are nocturnal in nature so they tend to spend a lot of the day hiding in the rocky structures around the exhibit. You’ll see their heads and part of their bodies sticking out. However, we often see them swimming around throughout the day. They even like to visit the divers when we are in the exhibit. Also, be sure to visit the aquarium on a Sunday, Tuesday or Thursday at 3:30 to watch the shark feed! The eels are often seen coming over for a snack as well. Look fast! Maybe you’ll just catch that pharyngeal jaw in action!

Invasive Species in the Great Lakes

April 14, 2016

Written by Greater Cleveland Aquarium

Sometimes it’s easy to take for granted those big bodies of water next to us known as the Great Lakes. But did you know…the Great Lakes hold the largest supply of surface freshwater in the world? And that they provide drinking water to 40 million(!) U.S. and Canadian citizens? This is just the tip of the iceberg in regards to the importance of the Great Lakes. Also of relevance are the economic windfalls of these waters, and the lure of tourist attractions, plus a multitude of other factors that make them so valuable. But sadly, they’re facing major problems. Together, we have to figure out ways to keep these beautiful lakes safe.

One very big reason why the Great Lakes are in danger is due to invasive species. An invasive species can be described as an organism that has successfully established a population where it’s not originally from.

In all, there are around 180 invasive species causing havoc around these ecosystems. Each one makes their presence negatively felt in various ways. In general though, these pests will out-compete our important native species and push them out of their homes. The food chain becomes severely disrupted by these invaders, and the habitat overall degrades. Invasive species cause enough negative ecological impacts to the plants and animals that share their space, but what about us? Why should we care about them?

Most people probably don’t realize that we’re all paying for invasive species in our lakes, whether it be with our health or with our money. Overall, these invaders cost residents and businesses of the Great Lakes basin over hundreds of millions of dollars per year. We see spikes in our water bill when extra efforts have to be made to keep it clean and safe for drinking. Food prices will also increase due to invasives lowering the population of popular commercial eatery fish. Prices are going up, while our health might possibly be going down. For example, zebra mussels can contain harmful toxins in their systems, which are then passed up the food chain to larger animals consumed by us. Invasives can also be vectors for foreign diseases that we don’t yet have defenses against. The list of harmful effects goes on and on unfortunately.

One especially harmful invasive species can be viewed in our Aquarium’s very first tank you see when you walk in through the main entrance. Being the stuff of nightmares for some, the Sea Lamprey isn’t the prettiest fish to look at, and its effect on lake ecosystems is not pretty either. With its round, suction-disk mouth filled with sharp teeth, this lamprey has the ability to kill 40 or more pounds of fish during its parasitic lifetime. They’re not picky either, so their effect on the fishing business in the Great Lakes has been extreme.

Combating invasive species is no small task. It requires advanced and expensive methods to keep out and control these organisms. It will be much easier to accomplish this so long as new invasives aren’t popping up, which is where you at home come into play. When buying a live plant or animal from a pet store or bait shop, please do not release them into the wild at any time. It may be tempting and seem harmless to put your unwanted goldfish or turtle in the pond out back, but that’s exactly how invasive species problems can begin. The Great Lakes are a magnificent resource for ages of all kinds, and they’re under enough pressure from humans as is. The Lakes provide us amazing opportunities without having to drive for miles and miles, so the least we can do is protect them in return.

For more information, check out these great resources:

http://www.regions.noaa.gov/great-lakes/

http://www.nature.org/ourinitiatives/regions/northamerica/areas/greatlakes/explore/great-lakes-aquatic-invasive-species.xml

I See Sea Creatures Program

March 16, 2016

Education

Written by Greater Cleveland Aquarium

Hermit crabs, sea anemones, and urchins, oh my!

During our I See Sea Creatures education program, we investigate all sorts of animals living at the Greater Cleveland Aquarium. Designed to complement science and early reading goals for preschool and kindergarten students, this class is a fun way for young learners to explore our exhibits and learn about aquatic life.

Students count the arms of a sea star as it is added to the story board.

Beginning with an interactive story session, students are introduced to Eric Carle’s story A House for Hermit Crab. As the story is read, students create a visual story board to keep track of each animal the hermit crab encounters through his year long journey. We practice story sequencing, counting, and imaginative play.

After the story, students tour through the aquarium to find the living inspirations behind Carle’s characters. With the addition of our invertebrate touch pool, we get to meet many of the animals up close! Feeling the texture of a sea star, the spines of a sea urchin, and the hard cover of a snail shell, is a great way to discover the biodiversity of ocean life.

Students compare the soft cover of a sea cucumber to the rough cover of a sea star at our invertebrate touch pool.

To learn more about the I See Sea Creatures program, please visit our education page. We provide booking information, program descriptions, and even educational activities to do at home. Our teacher guides provide helpful resources for both parents and teachers; activities include math, science, music, sequencing, and make-your-own puppet printables. You can find the I See Sea Creatures guide here.

Wondering if hermit crabs really decorate their shells as Eric Carle describes in the story?

They do. Common Hermit Crabs, Pagurus bernhardus, host a variety of organisms on their shells including barnacles, protozoans, and polychaete worms. Hosting sea anemones, with stinging tentacles, adds the benefit of protection from predators. Most hermit crabs prefer shells with organisms over plain shells. Though these animals do not engage in polite conversation as they do in the book, check out the awesome video below and for more information on hermit crabs visit these resources:

http://animaldiversity.org/accounts/Pagurus_bernhardus/

http://www.arkive.org/common-hermit-crab/pagurus-bernhardus/#text=All

Symbiotic Relationships

March 2, 2016

Written by Greater Cleveland Aquarium

Symbiotic relationships occur all around us every day. They are quite simply relationships between two different species where at least one species benefits. There are three main types of symbiotic relationships: mutualism, commensalism and parasitism. Let’s focus today on mutualism, or a relationship where both organisms benefit from each other. The Greater Cleveland Aquarium has multiple examples of this happy relationship!

Let’s start out by taking a journey into our live coral exhibit, because that happens to be the site of not one, but TWO mutualistic symbiotic relationship. Both involve (you guessed it) coral! The first one involves a very famous movie star that goes by the name of Nemo. Now most people associate the clown anemonefish with anemones, hence the name. However, in this particular exhibit, the anemonefish has a relationship with a type of coral known as Ricordea florida, which doesn’t actually have a common name. This coral protects the anemonefish with its stinging tentacles, which the anemonefish are immune to because of a protective mucous coating. In return, the anemonefish gives protection to the coral by being aggressive and fighting away other fish that might otherwise prey on the coral. Also, the coral can feed on bits of food from the anemonefish’s meal. Everyone wins.

Coral play a role in our Aquarium in multiple mutualistic symbiotic relationships. The next one we’ll look at is the connection between coral and zooxanthellae. Zooxanthellae, if you’ve never heard of them, are plant-like microscopic algae that live within the tissues of coral. The coral, once again, offer a protected home with their stinging tentacles. The zooxanthellae also receive the compounds necessary for photosynthesis from the coral, which is why coral need clear, low-turbulent waters to grow in, so the sunlight can reach them. Once photosynthesis is complete, the zooxanthellae transfer up to 90% of the products to the coral, which include oxygen and carbohydrates. The most fun and beneficial part for us humans is that the zooxanthellae provide the coral with the many different vibrant colors that are seen on coral reefs.

Our next relationship takes place in our stingray touch pool where there’s an interaction between our stingrays and the cleaner wrasse. While a stingray is resting on the bottom, a cleaner wrasse will use that opportunity to swim up and start the process. The cleaner wrasse, as its name suggests, cleans the stingray of dead skin and parasites, essentially getting an easy meal. The stingrays stay clean while the wrasse stay full! In the wild, the stingrays would also be a form of protection for the wrasse but that isn’t an issue in our friendly touch pool. Be sure to look carefully for these cleaner wrasse. Not every guest notices them.

Our last symbiotic relationship covers one that pertains to us humans directly. One of the newer exhibits at the Greater Cleveland Aquarium is the invertebrate touch pool, which is home to many different invertebrates, including cleaner shrimp. In the wild, these shrimp would receive their food by removing external parasites and old skin from eels, groupers and other fish. Here at the Aquarium though, guests can walk up and place their fingers in the water for a free mini-manicure! The cleaner shrimp hop right on your fingers and start cleaning away. Now hopefully we don’t have any external parasites, but old skin we surely have – so that makes a great meal for the shrimp.

Keeping Moon Jellies

Animal Care

Written by Greater Cleveland Aquarium

Look up and inside of the smokestack of the old powerhouse you will find a chimney full of Moon jellyfish. A lot of work and care goes into maintaining this unique exhibit. Here’s a quick look at what goes on behind the scenes of our jellyfish exhibit.

Photo: Jellyfish life cycle…Jellies have a very unique life cycle in that they reproduce through both sexual and asexual reproduction.

Culturing Jellyfish
We are happy to say that all of our jellyfish have been cultured right here at the GCA! We keep several plates of jelly polyps in flow through bins to catch and collect ephyrae. When the polyps asexually reproduce, they go through a process called strobilation. Once the ephyrae (stage 5 of the jellyfish life cycle) break off from the strobila they are pulled through to the bottom collection bin. There are several methods used to induce the strobilation process. The best way we’ve found here is through dramatic temperature swings. Dropping the temperature by 10-15 degrees for about 7-10 days has the polyps strobilating in no time! Once the strobilation process begins, we will find about 50-100 new epyrae each day. As the ephyrae slowly grow into medusa they will be moved into an appropriately sized tank and eventually make their way up to the chimney display. This process will take about 2-3 months.

Photo: Moon jelly culture set up at the Greater Cleveland Aquarium

Jellyfish Exhibit Design
Jellyfish are not very good swimmers and rely on ocean currents to get around. This means that the exhibit design and flow is very important when keeping jellies in aquariums. Jellyfish are typically kept in a round shaped exhibit, called a kreisel or pseudokriesel. The round shaped exhibit with a spray bar, help push the jellies in a circular motion to keep them suspended off the bottom.

Photo: Pseudokreisel built at the Greater Cleveland Aquarium

Jellyfish Diet
In the wild, most jellyfish eat zooplankton. Zooplankton is made of many tiny aquatic animals. Adult brine shrimp (Artemia nauplii) are most commonly used for captive diets. Unfortunately, adult brine shrimp don’t have much nutritional value for jellyfish but juvenile brine shrimp are. Our jellyfish are fed 48 hour hatched Artemia twice day that are enriched with a concentrate algae diet. They are also fed a krill shake once a week for variety. The idea of a krill shake is to blend up a mix of large, nutritious fish chucks that would normally big too large for the jellies to eat.

Photo: Artemia nauplii culture set up at the Greater Cleveland Aquarium

Don’t Moon Jellies Sting?
Although there are species of jellies that can have a fatal sting, the sting of a moon jelly is incredibly mild. A sting from a moon jelly usually results in an itchy, red rash and not considered a danger to humans. Here at the aquarium, we keep a spray bottle of diluted vinegar nearby to help stop and neutralize the sting.