Invasive Species

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Tsunami Enabled Hundreds of Species to Raft Across Pacific

Thursday, September 28th, 2017

Biologists Detect Longest Transoceanic Rafting Voyage for Coastal Species

by Kristen Minogue

Barnacle-coated boat with Japanese characters washed up on beach

A Japanese tsunami vessel washed ashore in Oregon, coated in gooseneck barnacles. In a new study, scientists detected 289 species that rafted from Japan to the U.S. on tsunami debris, and they suspect many more were undetected. (Credit: John Chapman)

The 2011 Japanese tsunami set the stage for something unprecedented. For the first time in recorded history, scientists have detected entire communities of coastal species crossing the ocean by floating on makeshift rafts. Nearly 300 species have appeared on the shores of Hawaii and the U.S. West Coast attached to tsunami debris, marine biologists from the Smithsonian Environmental Research Center, Williams College and other institutions reported in the journal Science on Thursday.

The tsunami formed March 11, 2011, triggered by an earthquake of 9.0 moment magnitude that struck Japan the same day. When it reached the shore, the tsunami towered 125 feet (38.38 meters) over Japan’s Tōhoku coast and swept millions of objects out to sea, from small pieces of plastic to fishing boats and docks. These kinds of objects, scientists said, helped the species attached to them complete the transoceanic journey.

“I didn’t think that most of these coastal organisms could survive at sea for long periods of time,” said Greg Ruiz, a co-author and marine biologist at the Smithsonian Environmental Research Center. “But in many ways they just haven’t had much opportunity in the past. Now, plastic can combine with tsunami and storm events to create that opportunity on a large scale.”

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Q&A: Sherman’s Lagoon Cartoonist Jim Toomey on Ocean Conservation with Comics

Tuesday, September 12th, 2017

by Kristen Minogue

Artist with cartoon shark and cartoon sea turtle looking over his shoulder

Cartoonist Jim Toomey with two of his characters, Sherman the shark and Fillmore the sea turtle. (Image courtesy of Jim Toomey)

Since 1997, a great white shark named Sherman has put a wacky spin on life underwater in the comic strip Sherman’s Lagoon. Jim Toomey, the comic’s creator and conservationist, uses Sherman and his (usually more intelligent) friends to reveal real issues facing the ocean. In this Q&A, Toomey describes adding humor to environmentalism, and what happens when Sherman’s Lagoon meets Chesapeake Bay. Edited for brevity and clarity.

Want to dive deeper? Watch Jim Toomey’s TED Talk online. You can also meet Toomey at the Smithsonian Environmental Research Center October 17 at 7pm, for his free evening lecture, “Drawing Inspiration from the Sea.” Details here.

What first sparked your interest in the sea?

I was a little boy, maybe six, seven, eight years old….Some of the TV shows I used to watch, the Jacques Cousteau specials and things were somewhat unique. And it just fascinated me. It really captured my imagination to see this team of scientists explore this completely alien world. Click to continue »

Tidings from the Sunset Coast (3)

Thursday, August 3rd, 2017

Countin’ Crabs at Seadrift Lagoon

by Ryan Greene

Green crabs piled on top of one another.

European green crabs (Carcinus maenas) caught in Seadrift Lagoon (Stinson Beach, Calif.). Credit: Ryan Greene/SERC

The Smithsonian Environmental Research Center’s (SERC) largest west coast outpost, SERC-West, sits on San Francisco Bay in Tiburon, California. SERC’s main campus is 2,000+ miles away on the Chesapeake Bay in Maryland. In an attempt to bridge this distance, we’ve launched Tidings From the Sunset Coast,” a summer series highlighting the work at SERC-West. Our most recent story was a spotlight of our summer interns. This post is about the invasive European green crabs in Seadrift Lagoon, just north of San Francisco. Enjoy!

How many crabs are in the lagoon? This question may sound like the middle-school carnival contest of how many jelly beans are in the jar. But for ecologists at SERC-West, it’s no guessing game—the health of an ecosystem hinges on the answer.

A view across water with houses, a mountain, and hanging mist.

Seadrift Lagoon is about 20 miles north of San Francisco Bay, and it’s said to have the highest density of European green crabs on the West Coast. Credit: Ryan Greene/SERC

Since 2009, Smithsonian scientists have partnered with the University of California, Davis, and Portland State University to tackle a two-clawed problem in Seadrift Lagoon: Carcinus maenas, the invasive European green crab. Seadrift is a small subdivision surrounding an artificial lagoon that sits smack between the Pacific Ocean and Bolinas Lagoon at the northern tip of California’s Stinson Beach. In the early 1990s, green crabs began to take up residence here, and since then they’ve done their fair share of damage.

The primary problems with green crabs in Seadrift are that they’re hungry and there are scads of them. This lagoon houses the highest density of green crabs documented on the West Coast, and they eat a whole lot. In nearby sites, like Tomales Bay and Bodega Bay, green crabs have caused native bivalve populations to plummet, and in some cases they have edged out other native crabs. In Seadrift, the sheer number of green crabs suggests that the impact on the ecosystem may be similarly drastic. That’s why in 2009, scientists at SERC-West, UC Davis, and Portland State started working with community members and citizen science volunteers to remove the crabs from the lagoon. Click to continue »

Want Biodiversity? Love Your Enemies…Sometimes

Tuesday, August 1st, 2017

by Kristen Minogue

Three separate images of leaf infected by anthracnose, acorn with an insect hole and emerald ash borer.

Signs of three temperate forest enemies, left to right: Anthracnose (SERC), insect hole in an acorn (Jonathan Myers), emerald ash borer (Leah Bauer, USDA Forest Service Northern Research Station, Bugwood.org)

Walk through a forest in Maryland or Missouri, and you’ll probably find yourself surrounded by dozens of different tree species. Walk through a tropical forest in Brazil or Malaysia, and you’ll be surrounded by hundreds—in some forests, over 1,000. What’s behind this colossal difference in diversity? Scientists with the Smithsonian-led ForestGEO network came up with one morbid possibility: It may come down to having the right kind of enemy.

Earlier this summer, in a study in Science, researchers from 24 plots in the forest network from five continents pooled their data and detected a strange pattern: There’s a force at work in the tropics helping rare species thrive, a force that is much weaker in the cooler temperate zone.

Call it a clustering effect. The scientific term is “conspecific negative density dependence,” but it boils down to this: If too many trees of the same species grow in the same spot, they become magnets for enemies that slash their populations. In tropical forests, enemies generally knock them down just enough for new species to fill the gaps, without completely wiping out the first species. The result is a kaleidoscope forest with hundreds of species, many quite rare.

It may seem like a counterintuitive idea, that a lethal enemy could help sustain biodiversity. It can work when this thinning process prevents any one species from dominating.

“Just when a population is ready to take over, it catches a cold,” explained Sean McMahon, a co-author and forest ecologist with the Smithsonian Environmental Research Center (SERC). “And so it gets knocked back.”

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Tidings from the Sunset Coast (2)

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 (1)

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 »