Ecology

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Five Summer Activities That Can Spread Invasive Species

Thursday, June 15th, 2017
summerinvasives

Fishing, camping, and walking the dog can all have unintended consequences. (Credit: pixabay.com, 1,2,3. Used under Creative Commons CC0 license)

By Joe Dawson

Nothing seems to draw people outside like a beautiful summer weekend. A rain-free Saturday could mean taking the boat out on the water for some fishing or a family camping trip. Conservationists have found, however, that many summer activities carry the risk of spreading invasive species. A species gets the name “invasive” if it is not native to a location and causes environmental and economic damage. Here are five popular activities that can spread invaders–and tips for enjoying them safely: Click to continue »

Slime Nets and Other Invasive Parasites Unmasked, Thanks to DNA

Wednesday, May 31st, 2017

by Kristen Minogue

Zebra mussels in the Great Lakes, lionfish in the Atlantic and pythons in the Everglades: Large creatures like these generally draw the spotlight when talking about ways to combat invasive species. But for every visible invader, there are hundreds more too minuscule to see with the naked eye. These species often slip in unnoticed—and unregulated—in the ballast water of large ships.

“There have been reports of parasites being transmitted in ballast water, but most of those have been things that we can easily see,” said Katrina Lohan, a marine biologist with the Smithsonian Environmental Research Center. “So, the parasites that are hanging off the outside of fish.”

Lohan has made it her mission to track the invisible invaders. Click to continue »

Surprising Tree Emissions Show Forests Consume Less Methane Than Thought

Tuesday, May 9th, 2017

by Ryan Greene

White chambers attached to tree trunks. Multi-colored tubes run from the chambers to a black box in the undergrowth.

Methane flux chambers keep track of how much methane a tree trunk releases or consumes. Credit: Pat Megonigal/SERC

Rainbow-colored tubes snake through the undergrowth. White acrylic chambers sit mounted to tree trunks like giant bleached snails. At first glance, it’s not quite clear what the heck is going on. Cryptic as it may seem, these tubes and chambers are the key to a recent study showing that trees in upland forests are capable of emitting the planet-warming greenhouse gas, methane.

Scientists have long considered upland forests to be methane sinks due to the presence of methane-hungry microbes called methanotrophs in their soils. But new research by Pat Megonigal, an ecosystem ecologist who heads up the Biogeochemistry Lab at the Smithsonian Environmental Research Center (SERC), and Scott Pitz, a graduate student from Johns Hopkins, has shown that when it comes to upland forest methane cycling, soil isn’t the only game in town. Trees and their emissions are part of the equation too.

In a recently published study in New Phytologist, Megonigal and Pitz found that trees in upland forests are actually capable of emitting methane through their trunks. This means that some of the methane absorbed by methanotrophs in the forest soils may be offset by tree emissions.

Why, though, does any of this even matter?

When researchers think about global climate change, they need to think about heat-trapping greenhouse gases like carbon dioxide (CO2) and methane (CH4). Specifically, they’ve got to track these gases to see where they’re coming from (their sources) and where they’re getting stored (their sinks). Carbon dioxide receives much of the spotlight (and rightfully so, given its enormous impact on the global climate), but it’s also critical to keep an eye on methane. Although methane stays in the atmosphere for far less time than carbon dioxide, it’s capable of trapping up to 45 times more heat. In other words, methane is a big deal. If temperate forests are consuming less of it than we thought, as Megonigal and Pitz’s research suggests, that could be a big deal too. Click to continue »

Volunteer Spotlight: Lenore Naranjo

Thursday, January 26th, 2017
Lenore and Dan in the SERC education center.

Lenore Naranjo celebrates 10 years of volunteer, with SERC volunteer coordinator Dan Gustafson. (SERC)

by Sara Richmond, communications volunteer

In 2016, nearly 5,000 students and other visitors learned about the Chesapeake Bay ecosystem firsthand through education programs at the Smithsonian Environmental Research Center (SERC). They ventured on hikes and canoe trips, hauled in fish and invertebrates with seining nets, and studied the anatomy of blue crabs. SERC’s education programs are possible through the help of dozens of volunteers who lead field trips and assist behind the scenes. In the coming months, we’ll highlight the work of some of these volunteers in the SERC newsletter and on our blog.

Lenore Naranjo has been volunteering with SERC for over 13 years. After starting as a volunteer in SERC’s canopy labs, she began working with the education program, leading field study groups that give children a hands-on approach to a variety of marine habitats.

“We set up baskets with oysters, and they stay sitting on the bottom of the river through spring, summer, and fall, where they act as a habitat for fish and small critters,” she explains. During field trips, she pulls the baskets from the river bed and sets them in a tray of water so children can explore the baskets’ contents. “Some kids are very hesitant and don’t want to put their hands in something unfamiliar. But then they watch their friends who aren’t hesitant, and the next thing you know, they’re in there too, pulling out fish and crabs.”

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Natural Gas Trade Opens Door for Invasive Species

Friday, January 20th, 2017

by Kristen Minogue

Two scientists look at water sample on ship.

Marine biologists Kim Holzer (right) and Jenny Carney sample ballast water from a cargo ship in Virginia’s James River.
(Kim Holzer)

The U.S. is on the brink of a natural gas boom—but that could expose its shores to more invasive species, Smithsonian marine biologists report in a new study published this winter.

Over the last decade, U.S. natural gas imports have dropped as the country tapped into its own resources. Now, thanks to new technology that makes it easier to extract and store natural gas, it’s poised to be the world’s third largest exporter of liquefied natural gas by 2020.

“We’ve hit an inflection point,” said Kim Holzer, lead author and biologist at the Smithsonian Environmental Research Center (SERC). Exports haven’t yet reached historical import highs, but they are climbing.

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Ten Reasons We’re Earth Optimists After 2016

Friday, January 13th, 2017
Dawn Miller in forest

Ecologist Dawn Miller surveys trees in a SERC forest. (SERC)

by Kristen Minogue

The Smithsonian has a new resolution for 2017: Earth Optimism. This is the year the Smithsonian is celebrating environmental success stories, and shifting the focus to how we can fight battles to save species and preserve our planet—and win. Despite breaking a wide swath of climate records, 2016 gave us reasons for optimism as well. In our 2016 Year in Review, we’ve pulled out the most encouraging stories and discoveries at the Smithsonian Environmental Research Center from the previous year. Here are the top 10 that make us hopeful about the planet’s future:

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Dormant Orchids Need Fungi to Rise Again

Friday, January 6th, 2017

by Kristen Minogue

Green small whorled pogonia plant with flower

Small-whorled pogonia orchid, Isotria medeoloides.
(Melissa McCormick/SERC)

If you are a plant, when life aboveground turns harsh, you have few options. Some orchids respond by going dormant, spending years to decades underground before reemerging aboveground. But an army of the right fungi may help jolt them out of dormancy, ecologists from the Smithsonian Environmental Research Center (SERC) discovered in a new study published in the American Journal of Botany Friday.

Smithsonian scientists have been working to understand the ecology of one particular orchid – including why it enters and exits dormancy. The small-whorled pogonia is widely regarded as the rarest orchid east of the Mississippi. Federally listed as threatened, the orchid has vanished from Maryland and is endangered in 16 other states.

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Jekyll or Hyde? The Many Faces of Phragmites

Friday, December 16th, 2016

by Kristen Minogue

Scientist beside a Phragmites experiment on the water.

Pat Megonigal studies the invasive reed Phragmites australis on the Smithsonian’s Global Change Research Wetland.
(Tom Mozdzer)

It’s easy to dislike Phragmites. The invasive brown reed can grow over 15 feet tall and tends to crowd out anything in its shadow. But in the story of global change, Phragmites is a gray character, like Mad Men’s Don Draper, or the enigmatic Professor Snape. Beneath the surface, Phragmites australis—a European reed sweeping over East Coast wetlands—can empower wetlands to grow higher soils and possibly survive rising seas. Biogeochemist Pat Megonigal of the Smithsonian Environmental Research Center (SERC) prefers an analogy from classic literature: Jekyll and Hyde.

“The Jekyll part is that Phragmites helps marshes maintain elevation and keep pace with sea level rise,” he said. “The Hyde part is that they are poor habitat for native plants and animals.”

The latest discovery in Megonigal’s lab could tip things in favor of Mr. Hyde. Phragmites’ deep-growing roots were once thought an advantage that helps wetlands build soil. But those same roots could be disturbing ancient soils deep underground—triggering them to release planet-warming carbon dioxide (CO2).

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A Diverse Portfolio is Good for Oysters Too

Friday, December 2nd, 2016
Olympia oysters underwater

Olympia oysters (Matthew Gray/Oregon State University)

by Kristen Minogue

Act local. Diversity pays. Those two phrases could hold the key to saving young Olympia oysters, the only native oysters on the West Coast of North America. What they need are large networks of adult oyster beds to settle on—and a diverse “environmental portfolio,” finds a new study in Ecology.

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River Herring Have Better Shot at Comeback, Thanks to Underwater Sound

Wednesday, November 30th, 2016

by Kristen Minogue

For decades, efforts to conserve Chesapeake river herring have run into a black hole of uncertainty. Managers knew populations had plummeted, but no one knew how many remained. A team of biologists from the Smithsonian Environmental Research Center has found a way forward, recording the first complete spawning run of river herring in the Choptank River since the 1970s.

Their findings, published Tuesday in Transactions of the American Fisheries Society, give conservationists and managers a starting point: 1.3 million adult river herring migrating up the Choptank in one season.

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