Ecology

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Key to Oysters’ Future Lies in Past

Monday, May 23rd, 2016
Oyster midden

Typical American Indian oyster deposit, roughly 1,000 years old. (Torben Rick/Smithsonian)

by John Gibbons

Oysters have provided food for humans for millennia, and play an enormous role in sustaining estuaries around the world. Yet after more than a century of overfishing, pollution, disease and habitat degradation, oyster populations in the Chesapeake Bay and elsewhere have suffered dramatic declines. But for thousands of years,American Indians in the region harvested the shellfish from the Bay sustainably—a discovery published Monday that could offer clues for future oyster restoration.

Little is known about oyster populations prior to the late 1800s. On May 23 a team of Smithsonian scientists and other researchers published the first bay-wide, millennial-scale study of oyster harvesting in the Chesapeake in Proceedings of the National Academy of Sciences. Using fossil, archaeological, and modern biological data, the team was able to reconstruct changes in oyster size from four timeframes: the Pleistocene (780,000-13,000 years ago), prehistoric American Indian occupation (3,200 – 400 years ago), historic (400 – 50 years ago) and modern times (2000 to 2014).

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Biodiversity Protects Fish From Climate Change

Monday, May 16th, 2016

by Kristen Minogue

Fish provide protein to billions of people and are an especially critical food source in the developing world. Today, marine biologists confirmed a key factor that could help them thrive through the coming decades: biodiversity. Communities with more fish species are more productive and more resilient to rising temperatures and temperature swings, according to a new study from the Smithsonian’s Tennenbaum Marine Observatories Network and other international institutions.

The accelerating loss and rearrangement of species all over the globe have troubled scientists and the public for decades. But the question of whether biodiversity offers practical value—for humans and ecosystems—remained controversial. The new study, published May 16 in the Proceedings of the National Academy of Sciences, offers the most thorough proof yet that preserving marine biodiversity can benefit people as much as it benefits the oceans.

“Biodiversity is more than a pretty face,” said lead author Emmett Duffy, director of the Tennenbaum Marine Observatories Network and senior scientist at the Smithsonian Environmental Research Center. “Preserving biodiversity is not just an aesthetic or spiritual issue—it’s critical to the healthy functioning of ecosystems and the important services they provide to humans, like seafood.”

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Acidification and Low Oxygen Put Fish in Double Jeopardy

Tuesday, May 10th, 2016

by Kristen Minogue

Inland silverside with reflection.

Inland silverside (Menidia beryllina) reflected in aquarium. When threatened with low oxygen, fish often swim to the surface, where oxygen is more abundant but predators can more easily spot them. (SERC)

Severe oxygen drops in the water can leave trails of fish kills in their wakes, but scientists thought adult fish would be more resilient to the second major threat in coastal waters: acidification. A new study published Tuesday from the Smithsonian Environmental Research Center (SERC) shows that is not entirely true—where fish are concerned, acidification can make low oxygen even more deadly.

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Coffee, Carbon and Crime: 22 Reasons to Love Trees

Friday, April 22nd, 2016
Dawn Miller in forest

Ecologist Dawn Miller in SERC forest (SERC)

by Kristen Minogue

Friday is Earth Day, and this year it’s all about the trees. The Earth Day Network is on a mission to plant 7.8 billion trees in five years. Trees have enormous power when it comes to protecting the Earth. Scientists at the Smithsonian Environmental Research Center (SERC) have spent decades uncovering the environmental benefits of forests. But trees offer some advantages that are less obvious. Like acting as painkillers. Or improving your morning coffee. Since the holiday falls on April 22, we picked our top 22 things trees do for humanity.  Click to continue »

Amphibian Congregation: Sonic Songs of Spring

Wednesday, March 30th, 2016

by Heather Soulen

Sonic Cacophonies

American Toad (Photo: Tyler Bell)

American Toad (Photo: Tyler Bell)

It’s that time of year when much of the mid-Atlantic is waking up from a long winter’s slumber. Flowers are blooming, trees are budding, ospreys and eagles are nesting, and frogs are calling. Right now, the Smithsonian Environmental Research Center (SERC) is alive with the sonic cacophony of a two amphibians. Spring peepers (Pseudacris crucifer) and American toads (Anaxyrus americanus, formerly Bufo americanus) are shouting mating anthems from every available pocket of water. If you live east of the Mississippi River from Canada to Florida, you’ve likely heard their calls. But which is which? We’ve collected a few sound bites around SERC to help identify each amphibian’s call.

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The Everyday Naturalist: Fishing Spiders

Thursday, February 11th, 2016

by Jan Payne Wilson, SERC Volunteer

Six-spotted fishing spider (Dolomedes triton). Credit: Derek Ramsey

Six-spotted fishing spider, Dolomedes triton. Credit: Derek Ramsey

My dad was uncomfortable around spiders. Today we’d probably say he had a phobia. To deal with it, he found a spider-like creature, the Daddy Long Legs, and learned how benign and beneficial it was. From then on, he could focus on a “good spider” rather than his fear. As a child, I was indoctrinated with the knowledge that a Daddy Long Legs 1) could not bite you and 2) performed good deeds by eating “bad” spiders and other biting, child-frightening insects. Furthermore, they needed our help because they had delicate legs that easily broke off, so we moved them out of dangerous areas and avoided stepping on them. When I was older my father revealed that Daddy Long Legs weren’t actually spiders. Unlike true spiders, they can’t make silk and have neither fangs nor venom. From my father I learned that understanding a creature often changes fear into appreciation and, sometimes, amazement.

On the docks of the Smithsonian Environmental Research Center (SERC), I use my dad’s strategy to help students who either fear spiders or believe the only good spider is a dead spider.  With Daddy Long Legs it’s easy.  But we also have large spiders we don’t see as frequently: fishing spiders.  When you see your first fishing spider, it’s a hard sell to believe she’s got redeeming characteristics. Click to continue »

Hunt for a Missing Nutrient: Part III

Wednesday, February 3rd, 2016

by Kristen Minogue

Image: Tom Jordan beside a V-shaped weir that tracks nutrients in a SERC stream. (SERC)

Tom Jordan beside a V-shaped weir that tracks nutrients in a SERC stream. (SERC)

For years, a team of scientists has been trying to solve a mysterious disappearance at a drainage ditch on the Choptank River Basin, on Maryland’s eastern shore. Every year roughly 32,000 pounds of human-generated nitrogen enters the ditch’s watershed, from fertilizers, air pollution and other sources. But less than a third of that nitrogen typically flows out of the stream.

Tom Jordan has seen it before. A nutrient ecologist at the Smithsonian Environmental Research Center (SERC), Jordan has wrestled with the mystery of the missing nitrogen for more than twenty years.

“It feels like a sort of fatal attraction,” Jordan said. Two decades of trial and error and dead ends only fueled his determination to find answers. Now, according to a new January study, Jordan and his colleagues finally have some.

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Top 12 Highlights of 2015: Arctic Sailing, Cownose Rays and an Orchid Showdown

Thursday, December 31st, 2015

by Kristen Minogue

It’s been another wild year at the Smithsonian Environmental Research Center. We sent a sailboat to the Arctic, pitted our orchids in a showdown against the Hope Diamond and discovered a couple new species. And somewhere along the way we celebrated the center’s 50th anniversary. Scroll below for the 2015 #YearInReview, a collection of the top 12 stories, journeys and biggest surprises of 2015.

Image: Cownose Rays (Credit: SERC/Laura Patrick)

Cownose Rays (SERC/Laura Patrick)

Exploring the Ocean

Totes Adorbs! Cownose Rays Take Internet
These marine heartthrobs have earned a top billing. Besides making a 900-mile migration every year, which SERC marine ecologists are tracking with acoustic tags, the kite-shaped rays (whose mouths are stretched so that they seem to be wearing a perpetual smile) also won a Twitter #CuteOff in September.

What Does Life in the Ocean Sound Like?
Postdoc Erica Staaterman listens to the ocean for a living. Often seen as a silent landscape broken only by whale or dolphin songs, Staaterman is helping uncover a wealth of noise from the ocean’s hidden creatures. She shared some of the recordings with us in this edited Q&A.

Cruising the Arctic’s Forgotten Fjords
Ocean acidification researcher Whitman Miller sent one of his CO2-monitoring devices on a 100-day journey to the Arctic. Its mission: Venture to some of Greenland’s never-before-seen fjords and discover how melting glaciers are changing the water. And do it all in a small, 42-foot sailboat. Click to continue »

Phragmites vs. Climate Change: Invasive Reed Better at Taking Up Carbon

Tuesday, December 22nd, 2015

by Kristen Minogue

Image: Josh Caplan holds Phragmites. (Credit: Tom Mozdzer)

Ecologist and lead author Josh Caplan holds a Phragmites plant at the Global Change Research Marsh. Invasive Phragmites can grow up to 15 feet tall. (Thomas Mozdzer)

One of the Chesapeake’s least favorite invaders could end up being an unlikely savior. The invasive reed Phragmites australis, a plant that has exploded across Chesapeake wetlands in the last few decades, is also making those wetlands better at soaking up carbon, ecologists from the Smithsonian Environmental Research Center (SERC) and Bryn Mawr College discovered in a new study.

The common reed, better known as Phragmites australis, grows in dense clusters up to 15 feet tall. North America has several native strains that have co-existed peacefully with many other native plants for at least 30,000 years. It is the invasive strain that arrived from Eurasia in the 1800s that has scientists and environmental managers worried. Eurasian Phragmites grows taller and denser than North American Phragmites, crowding out many smaller plants, and blocking access to light and nutrients. These changes in plant community have a ripple effect on animals that rely on wetlands for habitat.

“The fish communities, the insect communities, the soil and invertebrate communities, all these things change when Phragmites comes in,” says lead author Josh Caplan, a Bryn Mawr postdoc and visiting scientist at SERC. Often, those changes aren’t for the better. “Phragmites is doing a number to these ecosystems.” Click to continue »

Restrictions in Seaweed Agar-vate Scientists

Thursday, December 17th, 2015
Bivalves from Panama for Dermo disease study

Bivalves from Panama for Dermo disease study

by Heather Soulen

Last week Nature magazine published a news piece about how supplies of agar, a research staple in labs around the world, are dwindling. Agar is a gelatinous material from red seaweed of the genus Gelidium, and is referred to as ‘red gold’ by those within the industry. Insiders suggest that the tightening of seaweed supply is related to overharvesting, causing agar processing facilities to reduce production. Most of the world’s ‘red gold’ comes from Morocco. In the 2000s, the nation harvested 14,000 tons per year. Today, harvest limits are set at 6,000 tons per year, with only 1,200 tons available for foreign export outside the country. In typical supply and demand fashion, distributor prices are expected to skyrocket. As a result, things could get tough for scientists who use agar and agar-based materials in their research.

Agar is a scientist’s Jell-O. Just like grandma used to make Jell-O desserts with fruit artfully arranged on top or floating in suspended animation within a mold, scientists use agar the same way. Bacteria and fungi can be cultured on top of nutrient-enriched agar, tissues of organisms can be suspended within an agar-based medium and chunks of DNA can move through an agarose gel, a carbohydrate material that comes from agar. Agar and agar products are the Leathermans of the science world.

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