Invasive Species

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Tidings from the Sunset Coast

Tuesday, July 25th, 2017

SERC-West Summer Intern Spotlights

by Ryan Greene

An intern in orange waders sprays a net hanging off the back of a boat.

Intern Elena Huynh helps clean a net during SERC’s annual zooplankton survey in San Francisco Bay. Credit: Ryan Greene/SERC

The Smithsonian Environmental Research Center’s (SERC) main campus is on the Chesapeake Bay in Maryland. SERC’s largest West Coast outpost, SERC-West, sits on the San Francisco Bay in California. To highlight SERC’s work out west, we’ve started “Tidings from the Sunset Coast,” a summer series about the life and times of SERC-West. Our first post explored California’s wet winter. This post features the stellar interns who are spending their summer at SERC-West.

Interns at the Smithsonian Environmental Research Center have the chance to work on independent projects while receiving personalized mentorship in a multidisciplinary atmosphere. Some people conduct experiments, others develop educational programs, and others (like me) write about the happenings at SERC. Simply put, SERC internships let you grow in whatever ways you want to be growing!

Check out the spotlights below to see what the interns at SERC-West are up to this summer. Click to continue »

Tidings from the Sunset Coast

Wednesday, July 12th, 2017

How California’s Record-Setting Rains Are Reshaping the Ecology of San Francisco Bay

By Ryan Greene

Clouds hang over the San Francisco skyline.

The San Francisco skyline as seen from San Francisco Bay. Credit: Ryan Greene/SERC

The Smithsonian Environmental Research Center’s (SERC) largest west coast outpost sits on San Francisco Bay in Tiburon, California. The Tiburon branch, affectionately known as SERC-West, serves as the nexus of SERC’s research activities on the western coast of North America. At a whopping 2,462 miles from SERC’s main campus on the Chesapeake Bay in Maryland, SERC-West can feel a bit remote. In an attempt to bridge this distance, we’re launching Tidings From the Sunset Coast,” a summer story series about all things SERC-West. The first snippet is a story about the wildly wet winter California experienced this year and what all this fresh water means for the marine life in San Francisco Bay. Enjoy!

A big band of clouds stretches from Hawaii to the western coast of North America.

Image from NASA’s VIIRS satellite show one of many “atmospheric rivers” which slammed the California coast this past winter. Credit: Jesse Allen and Joshua Stevens/NASA Earth Observatory

When it comes to rain in California, the last few years have been a feast-or-famine affair. After a bitter drought that sported some of the driest years on record, this past winter brought more precipitation than the northern parts of the state have ever documented. To put it lightly, the weather has been extreme. And while the wet winter has refilled reservoirs and beefed up the snowpack, leading Governor Jerry Brown to end the drought state of emergency in all but four counties, it has also wreaked its fair share of havoc.

Here at SERC-West, scientists have been following another part of this story: the bombardment of freshwater runoff that inundated San Francisco Bay this winter. All the fresh water from the rain drastically reduced the saltiness (a.k.a. salinity) of the Bay. For many plants and animals used to saltier water, this was simply too much to handle. The devastation has been widespread, and according to ecologist Andy Chang, who currently heads up SERC-West, in some areas, the changes to the ecosystem might be less than fleeting.

“We’re kind of expecting to see local extinctions of some species that were here before,” he says. Click to continue »

Q&A: Katrina Lohan, Marine Parasite Hunter

Friday, June 23rd, 2017

by Kristen Minogue

Katrina Lohan hiking in a forest

Katrina Lohan in New Zealand’s Abel Tasman National Park. (Credit: Chris Lohan)

Weird truth: There are more parasites on Earth than non-parasites. Katrina Lohan would know, having spent over a decade studying them. After five years with the Smithsonian Environmental Research Center’s Marine Invasions Lab, Lohan is now in charge of launching the center’s new Marine Disease Ecology Lab. In this Q&A, meet some of the weirdest parasites she’s encountered and learn how DNA is helping her unlock their secrets.

This is the second of three profiles about the young scientists heading SERC’s newest labs. Edited for brevity and clarity.

What do you find most fascinating about parasites?

I really like it when stories are complicated. And adding parasites certainly complicates any story. But I’m also intrigued by the David and Goliath aspect of it, that parasites are super small, [often] overlooked, and most people don’t even think about them in terms of what role they play in ecosystems or what they could possibly be doing. Most people would sort of shrug off—oh, they’re probably not really that important.  And yet, they’re extremely important. The more we learn about parasites, the more we realize that they control their hosts. They can actually completely change the behavior of their hosts. Click to continue »

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 »

Ships Struggle To Battle Invasive Species As Global Trade Surges

Monday, March 20th, 2017

Strategy To Flush Invaders From Ballast Water Coming Up Short

by Kristen Minogue

Woman descends gangway of large cargo ship.

SERC marine biologist Jenny Carney descends the gangway of a giant bulker ship in Virginia. When ships export coal and other goods, they return loaded with ballast water from foreign ports—and often inadvertently bring invasive species with them. (Credit: Kim Holzer/SERC)

In the battle against invasive species, giant commercial ships are fighting on the front lines. But even when they follow the rules, one of their best weapons is coming up short, marine biologists from the Smithsonian Environmental Research Center (SERC) discovered in a new study published in PLOS ONE Monday.

As ships move goods around the world, they often inadvertently ferry invasive species as well. These new species can come over in the ships’ ballast water—the water ships pump on board for stability, to keep them from becoming top-heavy. But when the ships arrive to port, they often discharge their ballast water from distant global regions, along with the unseen, unwanted hitchhikers.

Shipping companies and biologists have known about this problem for decades and are still struggling to combat it. Currently, their main strategy is called “open-ocean exchange.” The idea is to flush out ballast water from their original port in the open ocean, to remove most coastal organisms, and replace it with water more than 200 nautical miles from shore. When they arrive at their destinations and discharge their new ballast water, any open-ocean organisms they picked up are unlikely to survive in ports and coastal waters.

“Ballast-water exchange provides a stop-gap measure until new technologies can be implemented to further reduce species transfers,” said Greg Ruiz, SERC senior marine biologist and a co-author of the new study. Since 2004, the U.S. Coast Guard has required most commercial ships entering the U.S. from overseas to do open-ocean exchange before discharging ballast in ports. However, this strategy has some serious limitations and may not be as effective as scientists and policymakers once hoped. Click to continue »

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.

Click to continue »

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).

Click to continue »

DNA Unlocks Dirty Secrets of Blue Catfish Diets

Wednesday, October 12th, 2016

by Kristen Minogue

Large blue catfish held on boat by scientist.

Blue catfish SERC biologists dubbed “Megalodon,”  which they tracked moving almost 60 miles along the Patuxent River. (Brooke Weigel/SERC)

White perch, menhaden and darters: These are just a few favorite foods of Maryland’s invasive blue catfish, according to a new study from the Smithsonian Environmental Research Center (SERC). They’re also known to gorge themselves on larvae of channel catfish—and, occasionally, juveniles of their own kind.

The study, published in the journal Environmental Biology of Fishes, used DNA barcoding to get to the gut of what blue catfish prey on. Blue catfish arrived in Chesapeake Bay in the 1960s, brought by Virginia managers to establish a fishery. They quickly developed a reputation as voracious predators, threatening to devour many popular fisheries and edge out the Chesapeake’s native white catfish. However, to discover how much they could disrupt the ecosystem, marine biologists need to know exactly what they eat. The only way to do that is to look into their stomachs, where the majority of their prey has been reduced to almost-unrecognizable slop.

Rob Aguilar would know: A biologist with SERC’s Fish and Invertebrate Lab, he’s spent the last few years dissecting blue catfish stomachs and analyzing their insides. Click to continue »

Food for Thought: Cooking for Invasive Beetles

Friday, August 12th, 2016

by Emily Li

SERC intern Cole Caceres collects Japanese invasive beetles from hormone trap for his experiment

SERC intern Cole Caceres collects Japanese invasive beetles from a hormone trap for his experiment (Photo: Emily Li/SERC)

Smithsonian Environmental Research Center (SERC) intern Cole Caceres has two passions: science and cooking. He enjoys doing research and adding to the larger body of knowledge, but he hasn’t given up on owning his own restaurant. When he’s not studying nitrogen filtration as a laboratory assistant at the University of California, Davis, he’s probably watching Food Network or frying chicken wings in a sweet soy sauce glaze.

But Caceres found the perfect mix of his interests as an intern with SERC’s Terrestrial Ecology Lab. There, he cooks for invasive Japanese beetles, hoping to help shed light on their dietary preferences so that plant conservation initiatives can be more fully informed—one beetle bite at a time.

Click to continue »