Ecology

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Seeking Life in the Mud

Friday, June 13th, 2014

By Sarah Hansen

OLYMPUS DIGITAL CAMERA

Dean Janiak (left) and Ben Rubinoff collect a sample from the Rhode River.

Most of us think of the Chesapeake Bay as a single entity – one big body of water.  But Smithsonian Environmental Research Center (SERC) ecologist Dean Janiak and his intern, Ben Rubinoff, have a more nuanced perspective.  They’ve collected more than 150 samples from eight different habitats within the Bay and along its shoreline that contain mud, sand and lots of tiny animals.

Their ultimate goal: Discover how differences in habitats in the Rhode River (a sub-estuary of the Chesapeake Bay) can change biodiversity among creatures at the bottom of the river, and how those patterns change over time.  If it turns out that some habitats host more diverse animal communities than others, land managers can focus conservation efforts on those areas. Click to continue »

Invasive plant may protect forests from drowning

Thursday, June 12th, 2014

Citizen scientists brave dense swamps to find truth behind Phrag

By Sarah Hansen

JH bands a tree

Jack Hays bands a tree in the marsh.

Sea-level rise triggered by climate change affects coastal ecosystems first.  Marshes and wetlands along the shoreline creep inland, infringing on forest habitats.  Scientists have strong evidence that too much water will gradually drown the trees.  But an invasive reedy plant, known as “Phrag” from its scientific name, Phragmites australis, might be the forests’ unlikely protector, delaying drowning by about a decade.

Invasive Phrag (there is a native subspecies, as well) first came to the U.S. from Europe over 200 years ago.  The native variety coexists peacefully with other plants, but the invader takes over a habitat, choking off other flora.  Only recently, however, has its population growth exploded.   Scientists at the Smithsonian Environmental Research Center are trying to find out whether large Phrag populations in wetlands help or hurt tree growth.  It might seem counterintuitive, but scientists hypothesize that the Phrag is actually helping trees survive as sea level rises.  By removing some of the water, Phrag may prevent trees from drowning.     Click to continue »

The Strange, Controversial Way Plants Trap CO2

Wednesday, June 11th, 2014

by Kristen Minogue

Swamp Rose Mallow surrounded by blades of Schoenoplectus, a sedge in Drake's marsh experiment. (SERC)

Swamp Rose Mallow with blades of Schoenoplectus americanus, a sedge in Drake’s marsh experiment. (SERC)

Plants are among the world’s best carbon sinks, but there’s a side to the plant-CO2 love affair that’s rarely discussed. When carbon dioxide rises, plants cling to it more, releasing less back into the air—and until recently, scientists couldn’t figure out why. With a new paper published June 11 in Global Change Biology, ecologist Bert Drake believes he finally has the answer.

The process is called respiration, and it’s one of the most overlooked parts of the carbon cycle. Unlike photosynthesis, in which plants absorb carbon dioxide and release oxygen, respiration reverses it. And plants respire constantly. Much of the CO2 plants take from the atmosphere for photosynthesis finds its way back via respiration from plants and soil. Which leaves a major question: How much carbon can the world’s ecosystems store as CO2 rises and climate changes?

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Arctic Unguarded: Melting Ice Opens Way
for Invaders

Wednesday, May 28th, 2014

by Kristen Minogue

Arctic sea ice (Patrick Kelley/U.S. Coast Guard)

Arctic sea ice (Patrick Kelley/U.S. Coast Guard)


For the first time in roughly 2 million years, melting Arctic sea ice is connecting the north Pacific and north Atlantic oceans. The new sea routes leave both coasts and Arctic waters vulnerable to a large wave of invasive species—a problem the Arctic has largely avoided until now.

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Ancient Native American Compost Still Enriching Forests

Wednesday, April 30th, 2014

by Kristen Minogue

Photo: An open pit exposes a 3200-year-old shell midden. Native Americans used middens as trash piles for oyster shells, animal bones and pottery. (by Torben Rick/Smithsonian)

An open pit exposes a 3200-year-old shell midden. Native Americans used middens as trash piles for oyster shells, animal bones and pottery. (Torben Rick/Smithsonian)

More than 3,000 years ago, Native Americans dined on shellfish from the Chesapeake Bay, and the leftovers from those feasts are still benefiting modern-day forests.

Native Americans inhabited the Chesapeake Bay area more than 13,000 years before the first Europeans dropped anchor. During the Woodland period (3,200 to 400 years ago), they ate eastern oysters and threw the shells, along with animal bones, pottery and other shellfish remains, into trash piles called shell middens. Those piles enriched the soil with nutrients, promoting hot spots of native diversity along the Chesapeake shoreline.

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Nonnatives in Your Garden:
A Curse or a Blessing?

Tuesday, April 29th, 2014

by Kristen Minogue

Three nonnative flowers in Maryland. Left to right: Queen Anne's Lace, Moth Mullein and Lesser Celandine. (Susan Cook Patton)

Three nonnative flowers in Maryland. Left to right: Queen Anne’s Lace, Moth Mullein and Lesser Celandine. (Susan Cook-Patton)

“I just want to plant something that will grow in my yard. If a nonnative species grows better than a native, why shouldn’t I plant it?”

It’s a valid question, one that SERC postdoc Susan Cook-Patton remembers hearing from her father while still in high school. In the quest to preserve native plants, it’s become almost taboo to talk about the benefits of nonnatives. But not all nonnative plants are rampant invaders, and sometimes they could be good for gardens as a whole. Cook-Patton broke down the pros and cons of gardening with nonnative species at the Smithsonian Environmental Research Center’s first evening lecture on April 15. Here are a few to consider when deciding what to put in your garden:

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Diversity Helps Forests Resist Deer

Tuesday, April 8th, 2014

by Kristen Minogue and John Parker

White-tailed deer. (Photo courtesy of John Parker/SERC)

White-tailed deer. (John Parker/SERC)

In deer-populated forests, tastier plants can avoid being eaten if they are surrounded by less appealing plants. But with deer gone, diverse plots become weaker and plants are better off sticking to their own kind.

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From the Field: Two Weeks in Panama

Friday, April 4th, 2014

Linda McCann is a marine biologist studying invasive species with the Smithsonian Environmental Research Center. This March she and three other researchers spent 17 days exploring marine life on both sides of Panama, at the Smithsonian Tropical Research Institute (STRI).

Sloth in Isla Galeta, near the Smithsonian's marine station on the Panama Canal. (Photo: Kristen Larson/SERC)

Sloth in Isla Galeta, near the Smithsonian’s marine station on the Panama Canal.
(Kristen Larson/SERC)


March 10
Got up at o-2:30 to catch a shuttle to the airport, after singing a concert the night before and not getting to bed until 12:30. Finally arrived at our lodging in Panama about 10:30 p.m., bleary-eyed but happy to be back in this special place!

March 11
Our first day. Usually we start out a bit slowly, shopping for food, getting our IDs at Tupper, getting set up, but today we dive right in. We collect samples from the STRI dock in Naos and begin the process of reacquainting ourselves with the species in Panama. Warmer water means we are looking at a whole different suite of species than we see back in San Fran or Chesapeake. The lab is on an island situated just outside the canal on the Pacific side.

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Intern Logs: Mussels and the Melting Arctic

Thursday, April 3rd, 2014

by Amanda Guthrie, Marine Invasions Lab Intern

Mytilus mussels in Point Judith Marina, Rhode Island. (Photo by Kim Holzer)

Mytilus mussels in Point Judith Marina, Rhode Island. (Kim Holzer)


Imagine after settling down on a place to stay, your home picks up speed and moves without any forewarning, bringing you along with it to a new place. You get off to explore. It seems livable and similar to home, but a few adjustments will be necessary.

This story would be possible — if you were a mussel, a barnacle, or a myriad of other intertidal organisms. Once there, these new arrivals are sometimes able to escape their predators at home and thrive—often at the expense of native species, or the ecosystem as a whole.

Such is the dilemma of Mytilus galloprovincialis, a mussel from the Mediterranean. Mytilus galloprovincialis is native to southern Europe but has branched out to numerous non-native regions around the globe. It is the most prevalent non-native marine species in South Africa. There, it not only competitively displaced native species but also catalyzed the decline of swimming crabs and the increase of whelks.

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The Secret Formula to Feeding 900 Babies

Tuesday, April 1st, 2014

Scientists uncover milk composition of naked mole-rat queens

by Micaela Jemison

Naked mole rats at the National Zoo (by Meghan Murphy)

Naked mole rats at the National Zoo (Meghan Murphy)

Parents normally feel the need to provide well for their kids. For humans, that number of offspring is usually in the single digits, but a naked mole-rat queen can have as many as 900 pups in a lifetime spanning up to 30 years.

Naked mole-rats live their lives entirely underground in Africa, digging tunnels in a perpetual search for plant tubers to eat. These bizarre creatures are unlike nearly every other mammal on earth in that the burdens of reproduction and milk feeding of young are placed solely on a single queen and are not shared among the females of the colony.

While this system may work well for insects like bees where the young are fed by a horde of workers and nurses, scientists were perplexed as to how this system works for a mammal where one mother must produce milk for her very large brood.

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