Posts Tagged 'national public radio'



Diane Rehm’s Environmental Outlook: Jellyfish And The Health Of The Ocean

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Earlier today, I spoke to NPR’s Diane Rehm about jellies and the impact that jellyfish population increases and expansion of some species’ geographic ranges are having on the health of our oceans.

Jack Cover at Diane Rehm show

With Bill Dennison and Diane Rehm at NPR.

Jellyfish first appeared around 560 million years ago (long before the time of dinosaurs). They’re 95 percent water, have no brains and no bones and no heart or blood, yet these gelatinous animals are among the worlds’ most resilient organisms.

The jellies simple body plan has remained relatively unchanged. But lately some scientists are concerned the animals are thriving too well – overrunning marine ecosystems, forcing nuclear power plants to shut down and filling the nets of commercial fisherman and shutting down fisheries around the world.

Some of the jellyfish species on exhibit here at the Aquarium.

Jellyfish species from top left (clockwise): blue blubber jelly, upside down jelly, spotted lagoon jelly, Leidy’s comb jelly

There are both ecological human-related issues causing an “explosion” of jellyfish populations around the world.

  • Over the years, climate change has raised the average temperature of the ocean. While this rise has negatively impacted organisms like coral, warm season jellies start breeding earlier and have longer active seasons.
  • Human activities, such as the over-fertilization of our lawns and farms, results in a runoff of excesses of nutrients into the Chesapeake Bay and ocean. This results in what’s known as an algal bloom. When the algae absorbs all of this nutrient run-off, it dies. Bacteria then feeds on the dead algae and removes all dissolved oxygen from the water – this process is called eutrophication and produces “dead zones.” Fish and crabs perish in these dead zones, but not the resilient jelly. Jellyfish can survive with low oxygen levels!
  • Jellyfish are opportunistic feeders. When food, like zooplankton, is abundant, they will grow rapidly and reproduce at a rapid rate. Excessively large jellyfish populations can out compete young fishes that also feed on zooplankton.
  • Some scientists speculate that the reproduction of jellyfish predators may also be giving jelly populations a boost. For example, all seven species of sea turtle will opportunistically feed on jellyfish when they are encountered. The largest species of sea turtle, the leatherback, feeds almost exclusively on jellies. Pacific populations of leatherbacks are currently at about 7 percent of their historic population levels. Human activities are the cause of sea turtle population declines. Overfishing has reduced fish populations that also feed on jellies.

To listen the full “Environmental Outlook” segment on Diane Rehm’s show, click here

Jack Cover

A Blue View: A Devastating Year for Manatees

A Blue View is a weekly perspective on the life aquatic, hosted by National Aquarium CEO John Racanelli.

From the smallest plants and animals invisible to the human eye to entire ecosystems, every living thing depends on and is intricately linked by water.

Tune in to 88.1 WYPR every Tuesday at 5:45 pm as John brings to the surface important issues and fascinating discoveries making waves in the world today.

May 15, 2013: A Devastating Year for Manatees

A Blue View podcast

Click here to listen to John discuss the issues
facing manatee populations in Florida.

Gentle giants with few enemies, manatee populations have nonetheless long been threatened. The species has been on the federal endangered species list since 1967, when the list was created, and has been protected by Florida state law since 1893. Thanks to this, manatee populations have grown in recent years.

Typically, manatee deaths and injuries are associated with boat strikes. In fact, you’d be hard-pressed to find a manatee without tell-tale propeller scars. But this year, a particularly aggressive red tide along Florida’s southwest coast has killed more than 265 manatees. Combined with other causes of death, more than 580 manatees have died out of an estimated population of 5,000—a staggering number that has erased those recent population gains.

Red tide is an algae bloom that occurs naturally every year, though the 2013 bloom has proven to be more deadly than any previous year on record. Characterized most often by a red discoloration of the water, the algae produces toxins that affect the nervous system of vertebrates. These toxins can settle on sea grass and blow through the air when waves break the algae apart. Since manatees eat up to 100 pounds of sea grass per day, this can have devastating effects.

Symptoms of red tide toxicity in manatees include muscle twitching, lack of coordination, difficulty breathing, and seizures, but they aren’t the only ones affected. It can also cause human respiratory distress, shellfish poisoning, and the deaths of other marine mammals, fish, and turtles.

So what can be done? The truth is, when red tide strikes, little can be done besides just waiting it out. Florida state wildlife officials believe that this year’s red tide is subsiding, but the effects of the bloom are likely to be seen over the next weeks and months, resulting in more deaths.

Several facilities in Florida are equipped to handle critical care of manatees, but the Lowry Park Zoo’s Manatee Hospital is the only one rehabilitating red tide patients. Not many have been rescued, though every life saved is a victory for this endangered species.

manatee

A manatee in rehabilitation at Lowry Park Zoo.

To date, 13 manatees with red tide toxicity have been admitted to the hospital for care. Staff members monitor each sick manatee around the clock until the danger has passed, holding up the manatee’s head so it can breathe. Once out of the red tide environment, manatees recover fairly quickly. Unfortunately, there really isn’t anywhere for them to go.

Manatees are migratory animals, and staff at the hospital don’t want to release their patients only to have them wind up in danger again. They are working with state and federal partners to determine when the manatees can be safely returned to the open waters.

Efforts are ongoing to understand why this year’s red tide bloom was so toxic and long-lasting. An uncommonly mild winter most likely contributed because the algae bloom didn’t die off as quickly as normal. Manatees swam right into the red tide in their search for warmer waters. There’s also speculation that phosphorus runoff from farms and lawns are been a factor in the red tide’s severity. The hope is that as scientists better understand the reasons behind this extraordinary red tide event, the lessons learned can better prepare us for the next time, and more manatees can be saved.

A Blue View: Seafood Fraud Uncovered

A Blue View is a weekly perspective on the life aquatic, hosted by National Aquarium CEO John Racanelli.

From the smallest plants and animals invisible to the human eye to entire ecosystems, every living thing depends on and is intricately linked by water.

Tune in to 88.1 WYPR every Tuesday at 5:45 p.m. as John brings to the surface important issues and fascinating discoveries making waves in the world today.

May 1, 2013: Seafood Fraud Uncovered

A Blue View podcastClick here to listen to John discuss
seafood fraud.
 

When we go to restaurants and grocery stores, most of us assume that we’re getting what we pay for. But as a recent study shows, that’s not always the case—especially when it comes to seafood.

Seafood fraud is not a new issue, but according to a recently released study from Oceana, it continues to be a pervasive problem. From 2010 to 2012, Oceana conducted a seafood fraud investigation, collecting more than 1,200 seafood samples in 21 states. Using a DNA barcoding technique, a short DNA sequence was obtained from each sample and then compared to a catalogue of sequences from more than 8,000 fish species. This DNA testing showed that 33 percent of the samples analyzed were mislabeled, though there was tremendous variation depending on the type of fish purchased.

Red snapper in particular was the most commonly mislabeled—113 out of 120 samples were a fish species other than red snapper. Twenty-eight different species were substituted for red snapper, and 17 of those weren’t even in the snapper family at all. In one instance, the red snapper was actually tilefish, which the government advises sensitive groups to avoid due to high mercury levels.

Also raising health concerns, escolar was a substitute for white tuna in 84 percent of samples. Escolar is a snake mackerel that contains a naturally occurring toxin and can have serious digestive effects on people who eat more than a few ounces. The Food and Drug Administration actually advises against the sale of this species, and some countries have banned it outright. Consumers are not protected, though, when it’s mislabeled as white tuna.

The Oceana study reports that 44 percent of retail establishments sold mislabeled fish, with sushi outlets far outstripping restaurants and grocery stores. In fact, 74 percent of sushi venues mislabeled fish, compared to 38 percent of restaurants and 18 percent of grocery stores.

There are many reasons that seafood fraud occurs. They include a lack of understanding, a desire to increase profits, and attempts to launder illegally harvested seafood. Somewhere along the supply chain, someone may substitute a lesser-valued fish. Others may short-weight the product, meaning the seafood processor misrepresents the weight of a seafood product so the customer gets less food for their money.

The consequences of this fraud are considerable. In addition to affecting human health when one species is swapped with another that may have contaminants, allergens, or toxins, seafood fraud disguises what is truly happening in the marketplace, incentivizing illegal fishing and threatening conservation efforts.

To address this critical issue, the SAFE Seafood Act was recently introduced to the House of Representatives and the Senate. This bill requires that seafood in the U.S. be traceable from its origin, standardizes seafood names, keeps illegally caught fish off the market, and increases inspections.

So what can you do to protect yourself from seafood fraud? Show curiosity about where your fish was caught and how. This will increase the dialogue around these important issues and hopefully encourage restaurants and stores to ask questions of their suppliers. Be knowledgeable about what you’re buying—and if the price seems too good to be true, it probably is.

A Blue View: Vernal Pools

A Blue View is a weekly perspective on the life aquatic, hosted by National Aquarium CEO John Racanelli.

From the smallest plants and animals invisible to the human eye to entire ecosystems, every living thing depends on and is intricately linked by water.

Tune in to 88.1 WYPR every Tuesday at 5:45 p.m. as John brings to the surface important issues and fascinating discoveries making waves in the world today.

April 17, 2013: Vernal Pools

A Blue View podcastClick here to listen to John discuss what vernal pools
and the important role they play for our woodland ecosystems. 

When most of us think of aquatic ecosystems, what usually comes to mind are oceans, rivers, bays, lakes, and streams. But there is another essential body of water, one not commonly known, that provides critical habitats for many woodland animals.

Vernal pools are similar to swamps or small ponds in appearance, but there’s one key difference: They fill and dry cyclically throughout the year. These temporary woodland ponds occur in shallow depressions and typically fill in the spring and dry out during the summer only to fill once again in the fall. Small in size, usually less than an acre, vernal pools are often surrounded by woodlands.

Several species of frogs, toads, salamanders, and numerous invertebrates use these pools as their primary breeding habitat, making their role in landscapes in the northeastern United States even greater than one might expect given their small size and temporary nature.

Vernal pools usually are at their deepest in the spring, which is where these pools get their name: vernal comes from the Latin “vernus,” meaning “belonging to spring.” They fill with rainwater, snow melt, and runoff from higher areas, and though small, they are literally teeming with life. The first warm rains of March and April set off mass migrations of frogs and salamanders from the surrounding woodlands into the pools, which provide a space for all sorts of plants, insects, and other animals to grow and thrive.

Take marbled salamanders, for instance. At summer’s end, many of the vernal pools are completely dry. By the end of September, prior to the onset of fall rains, hundreds of female marbled salamanders assemble and lay up to 200 eggs in depressions under logs, vegetation, and leaves in the lower areas of a vernal pools. The eggs are guarded until rains fill the low-lying areas, and the eggs hatch soon after coming into contact with water.

Fairy shrimp eggs that have been lying dormant in the dry mud also start hatching when these pools fill with water. Species such as wood frogs and spotted salamanders almost exclusively utilize vernal pools for breeding. Even mollusks, such as fingernail clams, can be found in vernal pools, surviving by remaining dormant in pool sediment during the dry season.

This wetland-then-drought cycle means that fish and other species that depend on permanent water cannot survive, providing an ideal habitat for the aquatic larvae of insects and amphibians. Any frog or salamander that lays its eggs in a vernal pool benefits by not having its offspring eaten by fish. These species would otherwise be challenged with competition or predation from larger aquatic species. The inhabitants of these vernal pools aren’t without predators, however. In April and May, snakes, turtles, birds, and mammals visit the vernal pools to feed on amphibians and their larvae. As the year progresses other species are drawn to vernal pools as well for food, water and shelter.

In addition to the providing a diverse ecosystem for wildlife, vernal pools help to gather and hold runoff from heavy rains, serving as storage tanks and settlement ponds for areas such as the Chesapeake Bay watershed. Without vernal pools, the runoff and silt load is increased and delivered directly into larger water sources.

Despite their vast importance, these wetland ecosystems are threatened. Because they are temporary, they are often not protected by wetlands laws. The study of these vernal pools is evolving, and ecologists are steadily increasing their understanding of these pools as a healthy habitat and breeding ground for many species.

This spring, you can see these vibrant ecosystems for yourself as you hike or bike through the forests of Maryland. These specialized, woodland wetlands can often be located by following the sounds of calling frogs. Take care not to disturb them, but by all means pause and look at the diversity of life that exists in these vernal pools.

A Blue View: The Chesapeake Bay as a Classroom

A Blue View is a weekly perspective on the life aquatic, hosted by National Aquarium CEO John Racanelli.

From the smallest plants and animals invisible to the human eye to entire ecosystems, every living thing depends on and is intricately linked by water.

Tune in to 88.1 WYPR every Tuesday at 5:45 pm as John brings to the surface important issues and fascinating discoveries making waves in the world today.

April 10, 2013: The Chesapeake Bay as a Classroom

A Blue View podcast

Click here to listen to John share ways locals
of all ages can get to know the Chesapeake Bay!

The Chesapeake Bay Foundation offers a variety of opportunities for all ages—students and adults—to learn about the Bay throughout the year. From field programs to professional development opportunities, learn what is available here.

The 46-foot workboat Snow Goose allows students to get up-close in their study of the dynamic relationship between the Port of Baltimore and the Chesapeake Bay’s Patapsco River. Serving as a classroom on water, all of the Chesapeake Bay Foundation’s boat programs are equipped with state-of-the-art water quality monitoring equipment, allowing groups to generate data instantaneously, including pH, temperature, dissolved oxygen, salinity, chlorophyll, and other indicators to build a complete picture of the health of the river. Participants can then compare their findings to the data of professional Bay scientists through on-board wireless laptops.

Learn more about the Baltimore Harbor Program and the Snow Goose here.

A Blue View: World Water Day

A Blue View is a weekly perspective on the life aquatic, hosted by National Aquarium CEO John Racanelli.

From the smallest plants and animals invisible to the human eye to entire ecosystems, every living thing depends on and is intricately linked by water.

Tune in to 88.1 WYPR every Tuesday at 5:45 p.m. as John brings to the surface important issues and fascinating discoveries making waves in the world today.

March 20, 2013: The Streams of Maryland

A Blue View podcastClick here to listen to John discuss the important role
freshwater plays in the survival of all living things!

Held annually on March 22, the United Nation’s World Water Day brings attention to the importance of freshwater and advocates for the sustainable management of freshwater resources. Globally, freshwater accessibility is critical for the survival of all living things, yet it is a significantly threatened resource. In Maryland, our own freshwater streams and rivers need our help as they run to the largest estuary in the United States, the Chesapeake Bay.

Even if you don’t live on the water, the health of the Chesapeake Bay watershed, which encompasses more than 64,000 square miles to six states and the District of Columbia, affects each of us every day. More than 100,000 streams, creeks, and rivers weave through the Chesapeake’s vast watershed. In fact, according to the Maryland Department of Natural Resources, we all live within 15 minutes of a stream, making freshwater health not just a Maryland issue, but a backyard issue as well!

Healthy streams are organically balanced, with enough oxygen to support life. Decaying plants and animal waste provide a balanced amount of nutrients, and the water is not too acid or too alkaline. In these healthy streams, runoff is kept to a minimum, and chemicals from farms, factories, and residential areas do not make their way into the stream. Countless species rely on healthy freshwater ecosystems to thrive. Fish, snakes, turtles, frogs, invertebrates…DNR states that Maryland is home to more than 100 species of fish, 20 species of salamander, and 10 species of turtle, just to name a few stream-dwellers.

diamondbackterrapin

The diamondback terrapin is just one of the many species of reptiles that rely on Maryland waterways!

In a recent assessment by the Environmental Protection Agency (EPA), just 45 percent of sampled streams in the Chesapeake Bay watershed were rated fair, good, or excellent. As outlined in the EPA’s Strategy for Protecting and Restoring the Chesapeake Bay Watershed, the goal is to improve the health of the watershed so that 70 percent of sampled streams measure fair or better by 2025.

To help increase our understanding of stream health, DNR coordinates a team of volunteers who collect important stream quality data across the state. This program, called Stream Waders, is the volunteer component of the Maryland Biological Stream Survey. The use of these volunteers allows more streams to be sampled, giving a big-picture view of Maryland’s waterways. Volunteers participate in a one-day training session, then spend a couple days in March or April collecting aquatic invertebrate samples from stream beds.

The study of aquatic invertebrates, such as mayflies, caddisflies, and dragonflies, is instrumental in the analysis of streams. Because invertebrates vary in their sensitivity to pollutants, a healthy stream has both sensitive and tolerant invertebrate species while an unhealthy one would have only pollution-tolerant species. Ultimately, the Stream Waders data is used in DNR reports and is available for review on their website.

In our daily lives, each of us can take steps to help keep our community streams healthy. Take a walk along a nearby stream and properly dispose of trash you find along its banks. Limit pesticide use in your yard so that it doesn’t make its way into freshwater supplies. Many local organizations host stream cleanups or wetland restoration events, so volunteer your time. Even just one day a year can make a real difference to a stream in your community.

Take action to keep our streams today by joining our Conservation team at one of our upcoming cleanups

A Blue View: Lionfish Invade Our Seas

A Blue View is a weekly perspective on the life aquatic, hosted by National Aquarium CEO John Racanelli.

From the smallest plants and animals invisible to the human eye to entire ecosystems, every living thing depends on and is intricately linked by water.

Tune in to 88.1 WYPR every Tuesday at 5:45 pm as John brings to the surface important issues and fascinating discoveries making waves in the world today.

March 13, 2013: Lionfish Invade Our Seas

A Blue View podcast

Click here to listen to John and aquarist Ashleigh Clews discuss 
the threat lionfish pose to the health of our oceans.

Since 1992, when Pacific lionfish were first sighted in South Florida waters, this fish has become widely established all along the southeast United States and the Caribbean Sea, even being spotted as far north as New York. These distinctive looking fish—red and white striped with long pectoral fins and needle-like dorsal fins, have profoundly impacted the health of the ecosystems where they now reside.

So, how were these species introduced into local waters? Ashleigh Clews, a senior aquarist at the Aquarium, says it’s likely that the species was first introduced by home aquarium owners. Although these fish are popular in the trade, they often outgrow their tanks and will sometimes prey on other fish.

There was an estimated population boom of 700 percent between 2004 and 2008 in invaded areas. This presence of lionfish in the Atlantic is causing many problems. They’re eating native fish and crustaceans and destroying native habitats and ecosystems. Additionally, with no real predators and an average spawn rate of close to 2 million eggs a year, this species shows no sign of disappearing on its own.

Conservationists and researchers are working to address this growing problem through a variety of initiatives, including raising awareness of lionfish as a sustainable seafood option!

Have you ever eaten lionfish? Tell us about your experience in the comments! 


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