Tuesday, July 29, 2014

Does the Aquarium Raise Fish?

The NC Aquarium at Fort Fisher is home to thousands of fish and many people wonder where they all come from. There are many different ways the Husbandry staff populates exhibits. We are often asked if we raise our own fish, and the answer is yes. Fort Fisher staff is researching and working on new ways to grow fish from egg to adult within the Aquarium.

While on exhibit, animals ideally show natural behaviors which often involve laying eggs. There are three main ways fish reproduce. Some fish are bearers, when one parent internally carries the eggs through development. Others are demersal spawners, laying eggs in a nest and guarding them until they hatch.  Lastly, pelagic spawners release millions of eggs to be fertilized as they flow though the ocean. Many aquariums, including Fort Fisher, have succeeded in raising the larvae and fry (baby fish) from bearers and demersal spawners, like our amazing seahorses, small neon gobies and stingrays. However, the majority of Aquarium fish are pelagic spawners. There are many opportunities to raise fish going (literally) down the drain.

Recently, we began a project to collect and raise some of these free-floating eggs. The healthy, fertilized eggs float to the top of the water. Specially built collecting equipment skims the top layer of water, collecting hundreds, and sometimes thousands, of eggs.

Larval rearing system at NCAFF
Pelagic eggs hatch within 24 hours from being released. When the eggs hatch, the larvae are very small and undeveloped.  A special holding tank was developed to keep them gently moving as if in the ocean currents. Initially, there is no need to be concerned about food because the larvae have no mouths. Instead, they feed from an attached yolk for the first few days. When they begin eating, things get a little tricky. Fish larvae are picky eaters. The food has to be the right type, size, and even speed for them to go after it. They survive mostly on algae and copepods (tiny crustaceans).

Juvenile blue striped grunt from eggs collected in April

It takes a lot of trial and error to hatch and grow the pelagic eggs. So far, the Fort Fisher Husbandry staff has had success with blue striped grunt; collecting eggs from our largest exhibit, the Cape Fear Shoals, and raising the fish behind the scenes. We have collected many types of eggs from the Shoals and other exhibits. Each attempt moves us closer to a goal of raising more fish in a sustainable way at the Aquarium. 

Tuesday, July 22, 2014

Protect Yourself from Rip Current Dangers

You think about many things when going to the beach— sunscreen, chairs and the perfect parking spot. But you may not think about one of the most dangerous things about swimming in the ocean - rip currents.

Rip currents form when a low spot or break develops in a sandbar close to shore. This forces ocean water through a narrow opening out to sea and creates a channel of water flowing away from shore that can extend hundreds of yards offshore. Rip currents can occur any time at the beach but are most dangerous during high surf and high wave conditions.

Rip current at Carolina Beach, NC Photo courtesy of NOAA,
via Carolina Beach Police Department

Rip currents are the leading surf hazard for beach goers, particularly dangerous for weak or non-swimmers. Their speed is generally one to two feet per second but water speeds can reach as high as eight feet per second - faster than an Olympic swimmer can sprint. More than 100 drownings a year occur in the United States due to rip currents. Rip currents are also the cause of the majority of water rescues.

Rip currents can be tricky to spot on the beach. Here are a few things to look for:
  • A channel of churning, choppy water moving perpendicular from shore
  • An area of light, sandy color water different from the surrounding ocean water
  • Sea foam or debris moving steadily out to sea 
  • A break in the incoming wave pattern

photo credit: NOAA
 If caught in a rip current, keep these things in mind:
  • Don’t Panic. Remain calm to help you think clearly and conserve energy.
  • Don’t fight the current. Swim out of the current in a direction parallel to shore. Once out of the current’s pull, start to swim towards the shore.
  • Draw Attention. If you are unable to reach shore, draw attention to yourself so lifeguards and other beachgoers will spot you. Face shore, wave your arms and yell for help. If you are at the beach and notice someone in trouble, notify a lifeguard or call 911. Try throwing something that floats to the victim and yell instructions on how to escape the current. Do not try to rescue the person yourself. Many people drown attempting to save someone else.

Another useful tool to guard against rip current dangers are warning flags often flown by lifeguards. Different colors communicate rip current risk to swimmers. Observe the flag warnings and swim where lifeguard patrol the beaches.
  • Green means low risk.
  • Yellow indicates a moderate risk. Weak swimmers are discouraged from entering the water. 
  • Red warns of a high rip current risk with high wave and surf action. This category implies all swimming in the surf is life threatening.

Before visiting the beach check out the local National Weather Service website for rip current risks. In southeastern North Carolina, the NWS office out of Moorhead City prepares a map to highlight the rip current risk for our area.

To learn more about rip currents, visit the National Oceanographic Atmosphere Administration’s rip current overview siteHere you will find videos, games and more information about rip currents. 

Monday, July 14, 2014

Four Ways You Can Help a Sea Turtle

Sea turtles face many obstacles throughout their lives. Crabs, foxes and other natural predators dig up nests and eat the eggs. As hatchlings emerge from the nest, they are vulnerable to sea gulls and large fish as they enter the ocean.  As the turtles grow, they face other predators such as sharks.  These natural threats help keep sea turtle populations in balance.

Green sea turtle hatching. Photo credit: R. LeGuen
Unfortunately, sea turtles also face many human-created challenges.  Changing coastlines by erosion and replenishment can have both a positive and negative effect.  Large holes dug in beach sand can trap a nesting mother or hatchling turtles. Items left on the beach like tents, chairs and trash can prevent the turtles from getting to the water or a nesting site. If turtles ingest the trash, they can become ill. Bright lights from homes or businesses left on at night can disorient turtles emerging from a nest and cause them to move inland instead of to the ocean.  Once in the water, sea turtles face the threat of marine debris. They may eat it or become entangled in it.  Boat strikes also pose a danger, as do fishing nets and hooks.

Young loggerhead sea turtle at the N.C. Aquarium at Fort Fisher.
Photo credit: NCAFF
Due mostly to human activities, sea turtle populations have declined. All species found in United States waters are classified as threatened or endangered and are protected by the Endangered Species Act.

You can help protect sea turtles with these four simple actions:
Turn off the lights. If you live on the beach or are visiting, turn off your porch lights at night or install turtle friendly lighting (which may be as simple as using a light bulb of a certain color wavelength). 
Clean up. After a fun beach day, fill in any holes dug. Pack up everything you brought and dispose of all trash in proper receptacles. 
Slow down. Watch for turtles when out boating and slow down if you see any. Also, secure items in your boat so they don’t fly out and retrieve anything that does.
Make a call.  If you see an injured sea turtle or one caught in a net or by a hook, call the sea turtle emergency hotline in your state.

You can find additional information on the National Marine Fisheries website under the Office of Protected Resources or at the North Carolina Sea Turtle Project .  

Tuesday, July 1, 2014

Plastics, Marine Debris and a Healthy Ocean

It’s no secret, the ocean is a wonderful place. We use it for recreation, to support our economy through tourism and seafood, and it serves as a home for thousands of species of wildlife from the largest whales to smallest microorganisms. A healthy ocean matters.

The Ocean is not as healthy as it once was. One of the major reasons is marine debris. Marine debris is anything floating in the ocean that doesn't belong there. Sometimes it’s left there on purpose but most often it ends up in the water accidentally. The less plastic we use, the smaller our impact on the planet. Many ocean creatures are injured or killed by plastic through entanglement or by ingesting it.

No matter how far you live from the ocean, you can do something about marine debris.  Since the majority of marine debris is plastic, we can keep plastic out of the oceans by reducing the amount of plastic in our lives

Four R’s Can Help

Refuse to use unnecessary plastic. This may be the most important step in keeping plastic out of the ocean. Refuse single use, disposable plastics. Start small - refuse one piece of plastic a day.
     · Say no to straws for your drinks. You can purchase glass or stainless steel straws to keep handy.
     · Politely decline a plastic bag for one or two items you can easily carry. Carry a reusable bag and remember to keep  it with you.
     ·  Don’t accept plastic bags for takeout food.
     · Forget single use cups. Buy a reusable cup or bottle and fill it up. Many places will give you a discount for having your own cup.

Reduce the amount of plastic you use. Do a survey of plastic items that you use every day. Keep track for two weeks. What items can you do without?

Once you’re ready to seriously kick plastic out of your life, check out this website.

Reuse it. Plastic is a part of everyday life and not always easy to avoid. When you find yourself with plastics, be creative in ways to reuse. Find ways to reuse plastic bottles with clever ideas such as bird feeders, decorative flower planters, and art projects. Use plastic bags as trash can liners, wet clothing holder, dog walking clean up devices, and even art projects. Search the web for other, creative ways to reuse a variety of plastics. Check out suggestions on the Aquarium’s Pinterest page!

Recycle it. Finally, if you can’t refuse, reduce, or reuse plastic, then recycle it. Plastics can’t all be recycled the same way. Plastic bags can often go back to the store to be recycled. Learn more here.

Other types of plastic need special attention, too, such as bottle caps. Learn more here

Make the 4 R’s part of your life and do your part to keep the Ocean healthy. If you’d like to do more to help with Marine Debris check out the Marine Debris Tracker app from the University of Georgia.