Posts Tagged 'Sharks'



Animal Updates – April 13

Between our Baltimore and Washington, DC, venues, more than 17,500 animals representing 900 species call the National Aquarium home. There are constant changes, additions, and more going on behind the scenes that our guests may not notice during their visit. We want to share these fun updates with our community so we’re bringing them to you in our weekly Animal Update posts!

Check our WATERlog blog every Friday to find out what’s going on… here’s what’s new this week!

Baby Spotted Lagoon Jellies
Mastigias papua 

Our jellies lab welcomed a special delivery from the Oklahoma Aquarium: baby lagoons! They’re about a month and a half old right now, and we’ve never had this species this young before. Right now, they’re developing and growing in our jellies lab, and once they reach about four or five months old they’ll be big enough to go on exhibit.

Baby lagoon jelly

Right now they look just like tiny blue blubber jellies, but as they grow, they’ll develop spots and lose their bluish tint. Since they arrived, they’ve already started to sprout tentacles, and spots are appearing along the edges of the bells.

Jelly's first tentacle!

Quite a bit goes into giving these jellies what they need to grow and thrive. They have a high metabolism, so they’re fed at least three times a day, sometimes more. These sun-loving jellies are kept under a special metal halide light, which is a different spectrum than regular lights. Spotted lagoon jellies have a symbiotic relationship with the algae that live in them; the algae need the light to photosynthesize, and the jellies eat the waste products the algae make in the process.

Older spotted lagoon jelly

Breeding Season for Sand Tiger Sharks
Carcharias taurus
You may see staff members observing and monitoring the behavior of the sand tiger sharks in our Open Ocean exhibit. It’s breeding season for these sharks, and sometimes the males can get a bit aggressive.

Sand tiger shark

Did you know? Female sand tiger sharks do not have the expected single uterus – each female has two, and babies develop in both at the same time. In each separate uterus, the unborn pups eat each other and devour any still-unfertilized eggs until only one remains. Eventually one baby is born from each uterus – talk about survival of the fittest!

Be sure to check back every Friday to find out what’s happening!

Maryland: Help save the sharks!

Shark populations worldwide are in danger of collapse due to fishing pressures stimulated by the global demand for shark fin soup.  Every year fins from tens of millions of sharks are used for this traditional, but non-nutritional meal.  Many species have been depleted nearly to the brink of extinction.  The National Aquarium and its partners are advocating on behalf of legislation that will help eliminate the market for shark fins in Maryland.

Current Federal and Maryland laws banning shark finning control shark handling practices but do not restrict the number of sharks killed just for their fins, or the substantial market for shark fins which creates economic incentives to overfish sharks just for their fins.  One of the most effective ways to protect sharks is to eliminate the market for fins by prohibiting their sale.  California, Hawaii, Oregon and Washington have all banned the possession, sale, trade and distribution of shark fins, and now it’s our opportunity to lead.

With our support, the Maryland State Senate has passed the bill (Senate Bill 465) that would ban the possession or distribution of shark fins in the state.  Now, it will be heard in the House of Delegates.  This legislation will establish Maryland as the first state on the east coast to join these other states in ensuring we are not contributing to the supply and demand of shark fins.

What You Can Do!
If you live in Maryland, please contact your delegates and let them know you support the “Shark Fin Ban” bill.  They need to hear from you!

Thoughtful Thursdays: Save the Sharks!

Many people think of sharks as frightening, sharp-toothed predators, far from being in need of our protection. In fact, people are more inclined to believe that we humans need protecting from these creatures. This couldn’t be farther from the truth: shark populations worldwide are in danger of collapse due to fishing pressures stimulated by the global demand for shark fin soup.

Every year, fins from tens of millions of sharks are used for this traditional, non-nutritional meal. Many species have been depleted nearly to the brink of extinction. As predators at or near the top of marine food webs, sharks help maintain the balance of marine life in our oceans.

Shark populations must be protected from the practice of overfishing. The National Aquarium and its partners, including the National Wildlife Federation and Oceana, are advocating on behalf of legislation that will close loopholes in current legislation that bans shark finning. We welcome your support!

Why Sharks Need Our Help

Unlike many fish species, sharks are slow to mature and have very few offspring, making them vulnerable to overexploitation. The sandbar and sand tiger sharks are two species in our mid-Atlantic waters that have faced great fishing pressure. 

Sandbar shark

Sandbar Shark at the National Aquarium


The sandbar shark, which utilizes Delaware Bay as a pupping ground, can take up to 14 years to mature, has a gestation of 11–12 months, and gives birth to 6–10 pups. The females breed only every other year. These young sandbar sharks are closely tied to the health of the marine ecosystem.

Research shows that the massive depletion of sharks has cascading effects throughout the ocean’s ecosystems. In Maryland, the depletion of sharks has caused an increase in cownose rays in the Chesapeake Bay, which threaten the oyster industry.

In the 30 years the National Aquarium, Baltimore, has been open, sharks have gone from a commercial fishery the federal government declared underutilized to the brink of extinction. In that time, hammerhead shark populations in the Atlantic have decreased by nearly 93%. Since 1986, all recorded shark populations in the northwestern Atlantic, with the exception of mako sharks, have declined by more than 50%.

Scientists warn that continual overfishing of sharks has decimated the population, which continues to dwindle and cannot sustain the current rates. The International Union for Conservation of Nature Red List of Threatened Species estimates that 30% of open ocean sharks are threatened with extinction.

What We Can Do

Recently, the National Aquarium took a stand to support the 2010 Shark Conservation Act, but we need to do more. Current federal and Maryland laws banning shark finning control shark handling practices, but do not restrict the number of sharks killed just for their fins, or the substantial market for shark fins that creates economic incentives to overfish sharks for their fins.

One of the most effective ways to protect sharks is to eliminate the market for fins by prohibiting their sale. California, Hawaii, Oregon, and Washington have all banned the possession, sale, trade, and distribution of shark fins, and now it’s our opportunity to lead.

With our support, the Maryland Legislature has introduced bills (Senate Bill 465 and House Bill 393) that would ban the possession or distribution of shark fins in the state. This legislation will establish Maryland as the first state on the East Coast ensuring we are not contributing to the supply and demand of shark fins.

The National Aquarium’s shark expert, Andy Dehart, will be testifying at both hearings in February, and the Aquarium’s Director of Conservation Laura Bankey and Director of Government Affairs Mark Yost are working closely with our partners to support the legislation as it moves through legislative channels.

What You Can Do

Let your state representatives know you care about sharks, and all the species in the marine ecosystem that depend on them! Our partners at Oceana have initiated an online advocacy campaign to support the shark fin ban in Maryland. Sign our letter today, and help save the sharks!

A tale of two sand tiger sharks

We’re very excited to welcome two new sand tiger sharks to the Open Ocean exhibit at the National Aquarium, Baltimore.

Where did these sharks come from, and how did they get to the Aquarium? Watch this video to find out:

Whenever possible, the animals in our exhibits are bred right here at the National Aquarium, or at other zoos and aquariums across the country. The National Aquarium has successfully bred many species of cartilaginous fish, including Southern stingrays and cownose rays. Breeding programs reduce the need to collect animals from the wild.

Did you know? The Association of Zoos and Aquariums (AZA) maintains a forum where accredited institutions can swap animals—it’s like Craigslist for aquariums!

Breeding programs are not possible for some species, including the sand tiger shark, due to intensive resource requirements and logistical impossibilities.

For this reason, Andy Dehart, director of Fishes & Aquatic Invertebrates for the National Aquarium and renowned shark expert, and his team are leading the way for sustainable shark-collecting practices that put the safety and health of the animals first.

Sharks are collected using a long-line fishing technique that minimizes bycatch, or fish caught unintentionally, and “we modify our fishing hooks, sanding off the barbs, to reduce injury and handling time of the sharks,” says Andy. “We know that line fishing with barbless hooks means we catch less sharks, but that’s a trade off we’re happy to accept,” he continues.

The sharks are transported back to shore in a special shark-sized fish box on the Aquarium’s shark collecting vessel. If a shark is thrashing in the fish box, Dehart and other Aquarium staff will actually get in the box and “hug” the shark to keep it still to prevent any injury.

A big, cold, wet shark hug—now that’s dedication!

New parents for a shark

The new school year has just begun, and this first-grade class has already done something amazing: they raised the money to adopt a shark from the Aquarium!

From Mrs. Detter, the teacher:

“While reading a book about endangered animals, the children expressed their interest in adopting an animal from a nearby zoo or aquarium. After many voting sessions, the children decided to adopt a shark from the National Aquarium. To make this possible, we need to raise $50.”

Tracking money raised

This is how we are tracking our progress.

It didn’t take these dedicated first-graders long to raise the money needed to submit their adoption papers.

We did it!

WE DID IT!!!

Congratulations, Mrs. Detter’s class! You should be receiving your Aquadopt package before long. We hope you come visit “your” adopted shark sometime soon! All the information you need for planning a great field trip is at aqua.org/teachers. In the meantime, here are some fun shark facts for you:

  •  Baby sharks are called pups.
  • The sand tiger shark adjusts its buoyancy by burping—gulping and expelling air at the surface. This allows the shark to hover nearly motionless in the water.
  • The largest fish in the world is the whale shark, which can grow up to 41 feet long. And whale sharks have no teeth!
  • Sharks have no bones at all. Their skeletons are made of cartilage. Feel your ears and the end of your nose. Notice how they’re kind of squishy, not bony? That’s cartilage!
  • Any of you have a loose tooth? A shark may lose up to 1,000 teeth a year, or 30,000 teeth in a lifetime! Shark teeth are constantly replaced as they wear or break. The inside of a shark’s jaw has five to 15 rows of teeth that usually lie flat until the tooth in front of it falls out. When a tooth is lost, another rotates forward to replace it, usually within 24 to 48 hours. The process of tooth replacement in sharks is very similar to the movement of a conveyor belt or the steps on an escalator.
Sand Tiger Shark

Look at those rows of teeth!

  • The skin of a shark is covered in tiny scales or skin teeth called dermal denticles. These skin teeth point toward a shark’s tail, so a shark feels smooth if touched from head to tail but feels like sandpaper if felt from tail to head.
  • There are approximately 400 species of sharks in the world. At the National Aquarium, we have eight different species, including bonnethead sharks, nurse sharks, zebra sharks, sawtooth sharks, and sand tiger sharks.
Bonnethead

Bonnethead shark

Meet Zeke, the newest addition to our Wings in the Water exhibit!

Zoe the zebra shark—a long-time icon at the National Aquarium, Baltimore—now has a companion in our Wings in the Water exhibit!

Last week, we added a young male zebra shark to the tank. At about 4 feet long, the male zebra shark—named Zeke—is much smaller than Zoe, and he is also much lighter in color.
Zoe has been at the Aquarium for 12 years, and is estimated to be about 17 years old. Zeke is 2 years old.

Zeke the zebra shark

Zeke the zebra shark

Zebra sharks are so named because as juveniles, these sharks have dark bodies with yellowish stripes. As the sharks grow, the stripes break up and the pattern changes to dark spots on a grayish-tan background. Because of this change, zebra sharks are often referred to as leopard sharks.

Two more features make this shark difficult to confuse with any other: the prominent ridges running the length of the body and the impressive tail, which is nearly as long as the body itself.

Zeke has mostly lost his stripes, but you can see that his spots are much closer together than Zoe’s. He came to the Aquarium as a small pup in August 2010. Since then, Aquarium staff has cared for Zeke behind the scenes, and prepared him for introduction into the exhibit.

Part of that preparation included training Zeke to take fish from the end of a pole held at the surface of the water by Aquarium staff. For the safety of our animals and staff, the sharks at the Aquarium are always pole fed, not hand fed, by the divers.

Zeke is adapting and responding very well to his new environment. Be sure to look for Zeke the next time you visit!

30 fascinating fish facts

2011 marks the National Aquarium’s 30th anniversary year—a year that will honor the Aquarium’s successful past and highlight its future as a leader in global conservation and aquatic health. Turning 30 also gives us an excuse to celebrate, have fun, and create this list of 30 fascinating fish facts for your cerebral pleasure!

1. Fish are cold-blooded, which means their internal body temperature changes as the surrounding temperature changes.

2. About 96% of fish are bony fish. The rest are cartilaginous fish, like sharks, skates, and rays.

Electric eel

Electric eel

3. Electric eels can discharge up to 550 volts, using their shock as an offense for catching food or a defense to escape.

4. Only the front 1/5 of an electric eel contains vital organs. These are located directly behind its head. The rest of the body is comprised of organs that produce electricity.

5. Arowana have the ability to jump out of the water to catch prey such as insects, birds, and bats.

6. More species of fish are found in the Amazon River than in all of Europe.

7. Gar are known as “living fossils,” as their remains have been found dating back to the Cretaceous period.

8. The female seahorse transfers the eggs to the male’s pouch, where they are incubated until birth.

Red lionfish

Red lionfish

9. Red lionfish are beautiful in the aquarium, but potentially devastating to the Atlantic Ocean, as the first successfully invasive species.

10. The northern snakehead has the ability to gulp air and absorb oxygen through a modified swim bladder that functions much like a lung. This ability allows the snakehead to travel across land to move into new bodies of water.

11. Piranhas hunt in large groups called shoals, or packs.

12. The largest fish in the world is the whale shark, which can grow up to 41 feet long.

13. Baby sharks are called pups.

14. The sand tiger shark is the only shark known to adjust its buoyancy by burping—gulping and expelling air at the surface. This strategy allows the shark to hover nearly motionless in the water column.

Seven-spot archerfish

Seven-spot archerfish

15. The archerfish is named for its peculiar adaptation of shooting a stream of water like an arrow at its unsuspecting prey—a tasty insect perched on a branch above the water.

16. The male banggai cardinalfish incubates the eggs in his mouth and continues to hold the young within his mouth cavity after hatching to further protect them.

17. Feather blennies lay their eggs in empty oyster shells. These territorial predators use their strong jaws to snap up and eat small fish and crustaceans that venture too close to the oyster shells.

18. The green moray eel is really brown! The yellow tint of the mucus that covers its body, in combination with the drab background color, gives the fish its characteristic uniform green color.

19. Southern stingrays have a “live birth,” meaning that the eggs hatch within the mother’s body. The pups, up to 10 in a litter, average 9 inches across at birth. Before their live birth, stingrays’ “wings” are curled up like crepes.

20. Burrfish are covered with short, heavy spines that are always erect, unlike their cousins the porcupinefish, which have movable spines.

Porcupine fish

Porcupine fish

21. When feeling threatened, pufferfish quickly ingest water to inflate their bodies into a ball several times their normal size.

22. Flounders and sole are fish with both eyes on the same side of their head. One eye actually migrates to the other side during larval development. Like most flatfishes, these bottom-dwellers can change the color patterns on their skin to blend in with their environment. They bury themselves in the sand and, with both eyes facing up, wait to ambush unsuspecting prey.

23. Jellies have been around for more than 500 million years—they pre-date dinosaurs!

24. The lined seahorse is the only seahorse found in the Chesapeake Bay. It camouflages itself by developing leafy appendages and changing colors.

Clownfish

Clownfish

25. In a group of clownfish, there is a strict dominance hierarchy. The largest and most aggressive female is found at the top.

26. Clownfish and sea anemones have a symbiotic relationship. The sea anemone protects the clownfish from predators, as well as providing food through the scraps left from the anemone’s meals. In return, the clownfish defends the anemone from its predators and cleans it from parasites.

27. Some catfish create saucer-shaped nests by fanning the river or lake bottom with their tails. Several thousand eggs are deposited in the nest and are guarded until they hatch.

28. The toothless catfish is not really toothless. It has teeth in the back of its mouth. This bottom-feeder vacuums through the sand to find its food.

29. The Australia grunter fish is so named because it emits an audible grunting sound when handled out of the water.

Barramundi

Barramundi

30. Barramundi, a giant perch found in Australia, changes sex as it grows up, starting as a male. Upon reaching 19.7 inches in length, it become female. These fish can grow to up to 6.5 feet long!


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