All posts by molliemcneel

Space-like chambers deliver the wetlands of a warmer world

By Mollie McNeel
Medill Reports

Wetlands are typically filled with the sounds of crickets chirping, bees buzzing and frogs croaking. But at the Smithsonian Environmental Research Center (SERC) in Maryland, those are all accompanied by the whirring of motor-powered pumps. The pumps drive air from hexagonal carbon dioxide chambers to a greenhouse gas analyzer, helping scientists create a “wetland of the future.”

Scientists at SERC are attempting to predict how the warming climate associated with rising carbon dioxide levels will impact coastal wetlands with an experiment called SMARTX—Salt Marsh Accretion Response to Temperature eXperiment. It’s one of many futuristic experiments on the center’s Global Change Research Wetland. Continue reading

Is Your Plant Dead or Just Dormant?

Mollie McNeel
Medill Reports

If a gardener tells you that their plants had died and now have come back to life years later, you might think they’ve gone crazy. But actually, they may be on to something.

Some fully-grown plants can “hibernate” in the soil for up to 20 years, researchers from the Smithsonian Environmental Research Center (SERC) discovered and reported their findings in a study published in the May issue of Ecology Letters.

The so-called “Rip Van Winkle” plants, nicknamed after the fictional character who slept for two decades, include many species of orchids and some ferns.

Pink lady’s slipper (Cypripedium acaule), an orchid that can remain dormant for over 20 years. (Credit: SERC)

An international team of researchers, including two Smithsonian scientists, have been working to understand the patterns and causes of dormancy in a variety of adult plant species. Dormancy only occurs in some plants in a population in any given year, and depends on individual plant circumstances. If a plant produces a new shoot that then gets destroyed, the plant will more than likely remain dormant through upcoming growing seasons to allow time to stock up on its necessary nutrients. While dormancy in seeds has been widely acknowledged and studied for decades, dormancy within fully-grown plants is far more mysterious.

“There is this hidden stage we didn’t know about, and it’s much more widespread than people had previously appreciated,” said Melissa McCormick, contributing author on the study and SERC molecular ecologist.

Dennis Whigham (left) and Melissa McCormick (right), two Smithsonian ecologists who study dormant orchids. (Credit: Peter G. Cane and Yini Ma)

To date, this research is the most comprehensive and widespread study conducted on dormancy in adult plant species. Scientists studied 114 plant species in 24 different families, using data from a vast array of datasets and published studies on plant dormancy.

The team realized that whether or not a plant will go dormant often depends on what it will “cost” the plant to produce a sprout—and found that plants with shorter lifespans (around five to seven years) are more likely to go dormant.

This may be because plants with longer lifespans are able to stock up on nutrients and store them underground, which can then be used as a backup source to produce another shoot in case the first one dies. Plants with shorter lifespans may not have this ability, giving them fewer opportunities to produce a shoot and making it much more “costly” if it dies, McCormick explained. Therefore, plants with shorter lifespans and shorter root systems may be more cautious prior to initiating aboveground growth.

In McCormick’s words, plants have to decide, “If I produce a shoot and it gets eaten, do I have anything left to use to produce a shoot again in another year?”

Plants that go dormant have been found to remain underground for anywhere from one to over 20 years. Since the dormant plants aren’t adding any resources by photosynthesis, they’re likely obtaining resources from fungi—another key to being able to go dormant and emerge in the future.

Almost all plants on land form beneficial relationships with certain kinds of fungi. But fungi play a special role in helping orchids and other dormant plants survive underground. These fungi provide essential nutrients such as carbon, nitrogen and phosphorus while the plant is nestled under the soil and unable to photosynthesize.

The base of an Isotria orchid, dug up by an animal so its underground roots are visible. This plant has gone dormant in the past. The tiny green bud shows where it’s preparing to grow a shoot for next year. (Credit: Melissa McCormick/SERC)

“The fungal side [of this research] has changed over time,” explained Dennis Whigham, SERC plant ecologist and co-author. “It initially started out as asking which types of fungi are present and if we can grow them in the lab.” However, as genetic research evolved, researchers were able to use DNA to search for fungi in the soil. This allowed them to be able to take a soil sample, look at that sample and see if the fungus was present near specific orchid species. “Now, we not only can determine if the fungus is present, but we can see how much of it in the area as well,” said Whigham.

Prior to the international study, the research team thought dormancy would be more prevalent at colder latitudes and higher elevations, where the growing season is shorter. But to their surprise, they discovered dormancy was more common near the equator, where threats like disease, competition and predators are more severe.

“Plants up in high latitudes grow really slowly and are really long lived. These plants store a lot more materials such as nutrients below ground,” said McCormick. “In the tropics, factors such as climate are often more benign and predictable, but predators, competition and plant diseases are not.”

Discoveries like this could be critical for conservation in the coming years. When looking at plant populations—especially those of endangered orchids—it’s important to know that there could be more than meets the eye.

“We can’t just go out one year, see what’s going on and move on,” said McCormick. “It’s not going to give us the answers we need in terms of the species or understanding how these plants are reacting to environmental changes.”

This story was originally posted on the SERC website.

PHOTO AT TOP: Pink lady’s slipper (Cypripedium acaule), an orchid that can remain dormant for over 20 years. (Credit: SERC)

Getting to know sharks one tag at a time

Mollie McNeel
Medill Reports

Sharks. They’re everyone’s favorite underwater enemy. Between nerve-wracking drama’s like Jaws to stories about prehistoric mega-sharks, we have all but made the shark species a completely fictionalized being. But, scientists at the Smithsonian Environmental Research Center in Edgewater, Maryland, are changing that one tag at a time.

May 14, 2018—Our shark tagging adventure began with an eight-hour car ride from the SERC campus outside of Baltimore, down the East Coast of the United States to Morehead City, North Carolina. While others had planned on joining us, I was the only team member making the journey with Chuck Bangley, a SERC marine ecologist at SERC. So, we loaded our government issued mini-van, stopped at Dunkin Donuts and hit the road.

May 15, 2018, 7:00 am— “If you start feeling sea sick just remember, feed the fish not the birds,” instructed a crew member on the R/V Capricorn as he addressed the 10 passengers that would be heading out on today’s trip.

Chuck and I are among other researchers from the University of North Carolina’s Institute of Marine Science. Some of them are interested in sharks, just like Chuck, while some are looking for squid or eels.

Captain Joe stops for gas, filling up the 200-gallon tank before we head out to sea. “I don’t see many white caps out there yet, but storms are in the forecast, so it might get rough,” he says, clearly excited as he steers the vessel towards the open ocean.

Fisherman on the R/V Capricorn brings in a large net of fish.Photo: Mollie McNeel

First item on today’s agenda is to “trawl” for about 15 minutes. To do this, the deckhands lower a large net with wooden and metal pallets at the ends to drag along the seafloor, collecting bait for the rest of the journey. As we float along, our net following behind, we catch the attention of a pod of dolphins that trail the net closely, making an easy meal out of the fish that narrowly avoid the net and an exciting spectacle for all on the boat.

As we reel in the net and dump its contents on deck I hear Chuck call out with excitement, “Dogfish!” That’s the shark he was searching for.

Smooth Dogfish that was tagged by SERC. Photo: Mollie McNeel
A student from UNC places the shark on its back putting it into an unconscious state. Photo: Mollie McNeel

A UNC undergrad student grabs the small shark and places it in a black plastic tank filled with seawater. “Flip it over onto its back,” instructs Chuck. Doing this helps subdue the shark by putting it into an almost unconscious state. He readies his surgical equipment, slips on blue latex gloves and grabs a scalpel to tag the shark.

In order to implant the acoustic tracker, the study procedures require Chuck to perform a small surgery on the sharks. He gives the aquatic patient a small shot of lidocaine to numb the area, makes a small incision on the shark’s underbelly, inserts the small black cylindrical instrument and stitches the wound closed—all in under five minutes. After the procedure is complete, they roll the shark back onto its stomach, making sure it is alert and moving well before it gets tossed for a dive back into the ocean.

After sorting through the rest of the net full of fish – squid, crabs and some of the biggest shrimp I’ve ever seen (which the crew happily set aside for their dinners) we were ready to continue fishing for the “big dogs”— more sharks.

Our first stop was just a mile off the coast. The crew began lowering a line of buoys and metal fish hooks loaded with our bait, impaled but still flailing, into the water. One buoy, 10 hooks. That was the order we followed in a smooth and practiced routine.

Once the hooks were out there, we did what fishermen do best – we waited. An hour passed easily with talk of science, fishing stories and dreams of catching a great white. As our boat circled back around to pick of the first buoy, excitement filled the air. Members of the crew were ready pull in whatever was attached to the hooks, scientists ready to tag and measure sharks and me, ready to take photos and come face-to-face with “jaws.”

The first couple of hooks come up empty but then the frenzy starts – one, two, three sharks about 3-feet long each are pulled aboard. They are Sharpnose sharks, not a species Chuck is looking for, but ones UNC scientists are tagging in a separate study. Grab a shark – measure to the fork in its tail, to the tip of the tail – tag it – throw it back – repeat. Over and over I watched as this series was performed in a shark assembly line.

A scientists measures the length of a shark. Photo: Mollie McNeel

After about 30 hectic minutes, we had pulled in 15 sharks, none that can be used for SERC’s study but still an impressive population size that scientists rarely see on these trips. “I’m your good luck charm,” I say joking. To my surprise, the team agrees and tells me to forget the rest of graduate school and join the crew instead.

Next, we move farther off the shore to about seven miles out. We no longer can see land in any direction and the captain’s gadgets show that we are floating in water about 57 feet deep. The wind has begun to pick up causing swells about three feet tall to rock the boat side to side harshly. As I look out the window from the boats cabin one second I can see nothing but blue sky and the next the boat shifts and the window only shows dark blue water.

We repeat the buoy and hook pattern as we cast again in the deeper water. Everyone takes the opportunity to eat some lunch while we wait. “Goldfish crackers are a must while out on a boat,” says Lewis, a student from the UK who is at UNC working towards his doctorate. We take bets on how many sharks we will catch this round. The buy in is a quarter and I bet high with hopes that my luck will continue — “12,” I say.

Unfortunately, I didn’t win the bet since we only brought in two sharks. But, while the number was disappointing, the last catch was not. As we were nearing the end of the hooks, we pulled in a large Sandbar shark spanning about 5 feet long. She was not happy to be pulled up onto the deck and was flailing around violently, mouth open, teeth visible and bloodied from the hook. A deckhand jumped on top of the shark, straddling it and pressing down on its head to keep it from biting anyone on deck. The shark was quickly measured, tagged and shoved off the back of the boat into the deep waters.

Sandbar shark that was the last catch of the day. Photo: Mollie McNeel

After that excitement it was time to make the long trip back to the docks. Some people on board began conversations while others, me included, settled in for a nap in the sunshine.

As we reached the dock and gathered our belongings someone in the background asked Chuck if he thought the trip was successful. “Well, we are leaving with one more shark tagged than before, so I would say that is a success,” exclaimed Chuck with a smile as he stepped of the boat and back onto dry land.

PHOTO AT TOP: Smooth Dogfish Shark caught and tagged off the coast of North Carolina. (Mollie McNeel/Medill)

The hunt for the return of the river herring

Medill News Service journalist Mollie McNeel is writing a series of stories from  embedded reporting with field researchers for the Smithsonian Environmental Research Center in Maryland.  

By Mollie McNeel
Medill Reports

May 9, Potapsco River, Maryland. – I am out here standing waist deep in the middle of a roaring river, straddling a net while the tail end trails behind me catching sediments that will be used to detect river herring.

Kim Richie, the SERC research technician I am assisting today, yells from the banks, “You have five minutes of standing there so get comfortable!” I don’t mention that the cold water is slowly finding its way through my full-body “waterproof” waders. Instead I just stand there waiting for the sediments to collect and my right boot to fill with river water.
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Uncovering the past at the Smithsonian Environmental Research Center

Mollie McNeel
Medill Reports

Travel about an hour southeast of Baltimore and you’ll end up in a small Maryland town called Edgewater. Keep driving past the city limits and you’ll see a brown sign on the side of the road indicating that somewhere in the thick forrest to your left is the Smithsonian Environmental Research Center where I am an embedded reporter. A long windy drive with exactly nine turns will lead you to a clearing full of lab buildings and dormitories–my home for the next month.

May 2, 2018, Edgewater, Maryland. My first week as SERC has been a whirlwind of adjusting to dorm living (once again), meeting scientists and figuring out which of the many high-stakes research projects I will be reporting about. But one exciting event came Wednesday as I joined the team at the SERC archaeology lab.

I arrived at the old house turned work center around 9 a.m.—a few minutes before everyone really began arriving. As I watched each person walk through the old screen door, it was clear that they were genuinely happy to be there. But what I didn’t realize is that they were all volunteers. The SERC archaeology lab is run by “citizen scientists” under the direction of Dr. Jim Gibb, a senior archaeologist.

The Sellman house where the Archaeology lab is located. Photo by Mollie McNeel

The day was spent inside instead of at one of the dig sites excavating oyster shells, nails, ceramics and tobacco pipes–all evidence of a structure inhabited by humans. The digs needed to dry out after stormy weather the night before. “Go get your hands dirty” was my only instruction, so I followed two others into the “kitchen” where a large wooden table sat with buckets of artifacts at one end.

“We are going to wash everything we found last week” said one of the more experienced volunteers. After a quick tutorial on how to scrub the brick, glass and pottery just right I grabbed my toothbrush and began cleaning. While the puzzle pieces of the past may seem like rubble, they are giving clues to a picture of life during the 17th century.

Pieces of glass that are believed to have once been a wine bottle. Photo by Mollie McNeel

We found lots (and lots and lots) of brick pieces which mean there was some type of structure on the property. We found green and blue glass shards—some small and some large—which were used for wine and medicines. The most exciting piece for me was finding nails that had been handcrafted leading the archaeology team to believe this site was actually the blacksmith’s shop!

Brick rubble found during the dig. Photo by Mollie McNeel

As my time with the archaeology lab came to a close I had a new appreciation for the old structures around me. Seeing these people talk of who the blacksmith could have been and what it took to make these rusty nails we were holding made me realize history is not lost, we just have to dig for it.