Christina Simkanin prepares to dive to survey ascidians. (Credit: Natalia Filip, University of Victoria, BC, Canada)
by Emily Li
Smithsonian biologists are on the trail of invasive ascidians. But with roughly 2300 species worldwide, describing these marine filter feeders (also known as “tunicates” or “sea squirts”) for a Most Wanted sign is tricky. Some ascidians are solitary; some are social. Some breed sexually, some asexually. Some, like Botrylloides magnicoecum, form large colonies of what look like octopus tentacles ringed in gold and highlighter blue. Others, like Rhopalaea crassa, resemble a cross between ghostly butterfly cocoons and pastel-colored pencil grips, while Polycarpa aurata is bulbous and mustard-yellow, with navy-blue veins that flare into trumpets.
When they invade new territory, ascidians can leave trails of damage in their wakes—but not always in ways scientists predict. In a new study published in the July issue of Marine Biology, a team of Smithsonian researchers, including marine ecologist Christina Simkanin of the Smithsonian Environmental Research Center (SERC), tracked their invasions across North America.
What they found seemed simple at first: North America’s 26 non-native ascidian species have spread so much they’re now established along nearly 3000 miles of its coastlines. But a few surprises were hiding in the details.
Blanca Bernal extracts a soil core from a SERC marsh. (Credit: SERC)
Just beneath our feet, there’s a slumbering pool of carbon that has largely been ignored.
Earth’s deep soils store vast reservoirs of carbon centuries to millennia old. Left undisturbed, they can store that carbon for thousands of years longer. But if triggered, those reservoirs could release carbon dioxide (CO2) into the atmosphere, a team of scientists discovered in a new study from the Smithsonian Environmental Research Center.
Last fall, while volunteering in a plant lab at George Washington University in D.C., I heard about an experiment that was starting up at the Smithsonian Environmental Research Center (SERC). The project, a global warming simulation in the wetlands surrounding the Chesapeake Bay, was helmed by SERC research ecologist Roy Rich, an ecologist with an engineer’s mindset. I’ve been a wetlands enthusiast since I spotted my first blue Heron as a kid, and global climate change is, in my mind, the most pressing issue humans face today. I was ready to sign up. I met with Roy and asked the same questions I have since answered over and over again since joining the project in November:
Joe Dawson checks a control box for the underground heating cables that help raise temperature in the marsh plots. (Kristen Minogue/SERC)
We have a lot to thank pollinators for this National Pollinator Week. Not only do they provide every third bite of food, but they also add $217 billion dollars to the global economy and help support healthy ecosystems. But can we even identify a pollinator when we see one?
Picture pollinators—from fat, sunlit bumblebees hovering lazily from flower to flower, to yellow butterflies flitting among pollen-dusted petals in brilliant flashes of antennae and wing. If you’re feeling especially imaginative, you might think of the delicate, curved beaks of hummingbirds dipped into blossoms larger than themselves. But while bees and butterflies share the limelight, underappreciated pollinators from all walks, wings, and wades of life quietly help to create the next generation of flowering plants.
by Maria Sharova SERC citizen science program assistant
Maria Sharova (right) sifts through oyster shells in search of tiny mud crabs with intern Caroline Kanaskie. (Monaca Noble/SERC)
I started working at the Smithsonian Environmental Research Center (SERC) one year ago this month. It had only been two weeks since I graduated from college with a bachelor’s degree in anthropology. Like any recent grad, I was excited and nervous to start my first real job—and, frankly, I wasn’t entirely sure what to expect.
During my first week of work, I was involved with the Chesapeake Bay Parasite Project (a.k.a. the Mud Crab Project), a project that looks at the impact of an invasive, parasitic barnacle called Loxothylacus panopaei (“Loxo” for short) on native white-fingered mud crabs in the Chesapeake Bay. Like most of our volunteers, I’d never heard of either of these organisms, I had no idea why the project mattered, and I’d never been involved in any kind of ecology research before. I had no idea Loxo was able hijack a mud crab’s reproductive system, forcing them to nurse parasite larvae instead of crab larvae. Nor had I ever searched through crates of oyster shells looking for mud crabs the size of a quarter or smaller, as our volunteers were about to do. But in no time at all, I’d become an experienced mud crab finder!
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).
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.”
May 12 is Limerick Day, which among science aficionados is a time to wax poetic about the joys of research. Or not. When you’re an ecologist, sometimes research is muddy, smelly, or just plain weird. Electric skillets and marbles can become safety features. But then, the thrill of climbing a 120-foot tour can remind you why it’s all worthwhile.
While some limericists adhere rigidly to the anapestic meter, the one thing all limericks have in common is the familiar A-A-B-B-A rhyme scheme. So enjoy a few snapshots in verse about the lesser-known side of environmental science:
The Sweet Smell of Science Are those cow guts that make the lab stench?
Fatty acids make my stomach clench.
They smell like fish and feet
But the microbes must eat,
While my lab mates avoid my work bench.
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.
This year’s theme for SERC’s annual Open House is “Ecosystem Conservation: Where do you fit in?” In the broadest sense, this question got me thinking about people, ecosystem research and conservation. How do we conserve ecosystems and make realistic and manageable policies? As a scientist, science writer/communicator and artist, I decided to explore these question through art, specifically mosaics.
Using art as a way to raise awareness, express one’s thoughts or as a way to create dialog is one of the most wonderful and powerful things about art. Humans have been creating art for some 40,000 to 60,000 years and this timeline could extend farther back as new techniques and technologies become available and new cave art discoveries are made. Over the past decade some field stations and laboratories have incorporated arts and humanities into their programs. Many see it as an opportunity to communicate an agency’s mission, the scientific process, science discoveries and complex scientific concepts or areas of study. A recent essay in the Ecological Society of America’s Ecosphere explores the convergence of science, art and humanities and why it could be important to sustainability, ecosystem stewardship, ecosystem services and conservation strategies in the future.