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From the Field: Arriving in Panama

Thursday, December 13th, 2012

by Kristy Hill

Panama skyline (Kristy Hill)

I arrived in Panama City at 10 p.m. Saturday night, and as the plane started its descent into the city, my eyes widened at the sight of the city lights. It looked as if Clark Griswold had bedecked the entire city with Christmas lights! Tall buildings flashed extravagant multicolored light shows. I started getting that flutter of excitement in my stomach. I was about to spend two amazing weeks in Panama doing the science that I love!

I got through immigration and customs without incident despite my inability to speak Spanish well (yo hablo muy poco español). At any rate, I found my shuttle driver holding a sign with my name on it, so I felt pretty special as we walked out into hot and humid Panama.

My driver, Victor, showed me wonderful Panamanian hospitality. Luckily he spoke English very well and gave me a tour of the city on our way to the hotel. He recommended some places for us to visit if we had free time, and we talked about his experiences scuba diving in the Caribbean.

I arrived safe and sound at the hotel, where I managed to wake Katrina, who was already fast asleep with visions of sugar plums dancing through her head as I fumbled with my suitcases. I climbed into bed as well shortly thereafter and dreamt of Panamanian oysters dancing in my head…

Buenas noches!

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From the Field: Game Plan for Panama

Thursday, December 6th, 2012

by Kristy Hill, SERC marine invasions technician

Katrina Lohan packs rubber gloves, Ziploc bags and other field essentials for a science expedition. (Kristy Hill)

Katrina and I leave for Panama City in next week, so we’re gathering supplies and mapping out our game plan. We’re stoked to get this project rolling—beautiful surroundings and mandatory snorkeling in the tropics won’t be such bad work!

The critters we’re looking for grow on coral reefs, mangrove roots, sponges, pilings, sea walls and rocks. Our goal is to collect at least 50 to 60 oysters of three or four different species from three sites along the Caribbean coast. At each site, we’ll take water quality measurements such as salinity, temperature and oxygen content. We’ll take additional notes about the oysters’ habitats, such as their distance from the shore, the depth of the water, their proximity to ports or marinas, etc. We want to obtain as much data (or information) as possible so we can better understand the environment where the oysters and their potential parasites live.

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From the Field: Hunting for Parasites

Wednesday, December 5th, 2012

by Katrina Lohan, Smithsonian Environmental Research Center and National Zoo postdoc

Many people cringe when they hear the word “parasite”—not Katrina Lohan and Kristy Hill. Combined, the two of us have spent 12 years conducting research on parasites that infect bivalves (oysters, clams, mussels, etc.), crustaceans (crabs, shrimps, lobsters, etc.), and songbirds. We are both passionate about studying marine parasites and want to better understand how parasitism impacts marine animals. For the next few months, we’ll be searching for these parasites in waters all along the east coast of North America, from Maryland to Panama.

Katrina Lohan (right) and Kristy Hill are preparing to scour the coasts of North America for marine parasites infecting oysters and other shellfish. (Kim Holzer/SERC)

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Posted in Climate Change, Ecology, Fisheries, Invasive Species, Parasite Hunting, SERC Sites and Scenes, Water Quality | 1 Response »

Climate Change Stimulates Growth of Invasive “Super Weed”

Thursday, November 8th, 2012

by Kristen Minogue

Tom Mozdzer explores a patch of invasive Phragmites in SERC’s global change wetland.

Is it better to be a jack of all trades or a master of some? In the plant world, it’s possible to do both–and that could make a huge difference in deciding which plants dominate under climate change. This holds especially true for one: the invasive reed Phragmites australis. Its ability to alter its anatomy enables it to grow well in just about any environment, including one spiked with CO₂ and nitrogen, SERC ecologists discovered in a study published Oct. 31.

Plants like this are called “jack-and-master” plants. Typically, the most competitive plants surpass their neighbors through one of two strategies. “Jack-of-all-trades” plants do moderately well under most scenarios. Their competitors will surpass them when conditions are good, but if the environment becomes stressful, the jack of all trades will grow better. “Master-of-some” plants do very well under only a few conditions, so if the environment shifts in their favor, they are certain to emerge victorious. But a few types—the jack-and-master plants—can use both tactics. And the invasive Phragmites is one of them.

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Posted in Climate Change, Ecology, Invasive Species, Land Use, Publications, SERC Sites and Scenes | 1 Response »

Boaters: Beware of Hitchikers on the Hull

Thursday, October 11th, 2012

by Ian Davidson

Propellor of a transient boat, veiled beneath a thick layer of biofouling. (Ian Davidson)

If several pounds of plant and animal material were attached to the underside of your car, slowing you down and increasing your fuel costs, you’d probably be concerned enough to remove it. The same applies to boats. But since boaters don’t have easy access to the undersides of their vessels, it can often be a surprise to discover large communities of organisms residing and hitchhiking on their hulls and running gear.

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Undersea Parasite Impregnates Crabs, Male and Female

Wednesday, September 5th, 2012

by Monaca Noble

Infected crab. The sacs on its abdomen contain thousands of parasite larvae the crab will later release into the water.

The world is full of parasites that can force their hosts to do strange things. One such parasite lurks in Chesapeake Bay: an invasive barnacle that hijacks a mud crab’s reproductive system and impregnates it with parasite larvae—even if the crab is male.

The invasive parasite Loxothylacus panopaei (Loxo for short) is a type of barnacle, but looks and acts nothing like the typical barnacles growing on rocks along the shoreline. Loxo has a highly evolved life cycle, essentially custom-made for acting as a crab parasite. As a free-swimming larva, Loxo resembles a typical barnacle larva. A female larva infects a recently molted crab by burying into its shell. Once inside, she undergoes a series of changes and assumes control over the host crab, dictating major functions such as molting and reproduction.

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Posted in Ecology, Fisheries, Invasive Species | 1 Response »

Mangrove Tracking IX: To Catch a Tree Crab

Tuesday, July 31st, 2012

by Megan Riley

A large adult male Aratus eating a juvenile of its species. (Megan Riley)

As adults, mangrove tree crabs (Aratus pisonii) tend to forage on fresh mangrove leaves in the canopy. As omnivores, they will also prey on nitrogen-rich insects, larvae, and even juveniles of their own species. However, it’s unclear how these organisms balance their nitrogen requirements and other nutritional demands. This summer I have focused my research on addressing this question. Specifically, I am investigating how their diet choices affect their overall health and ability to reproduce.

In order to perform this research, I first have to catch the Aratus! Despite the abundance of these animals in mangrove stands on the Indian River Lagoon, tree crab hunting is a tricky business. Over the course of the summer, I’ve learned a number of tips for trapping the elusive crustacean…

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Posted in Climate Change, Ecology, Invasive Species, Mangrove Tracking: Letters from the Field | 1 Response »

Mangrove Tracking VIII: Beneath the Waves

Tuesday, July 24th, 2012

by Cora Johnston

The waters beneath mangroves are teeming with marine life, in part due to the refuge provided by the tangled complexity of their underwater roots. (Cora Johnston)

From salty branches to mucky roots, mangroves are teeming with life. Although many people recognize mangroves as spindly trees emerging right out of the water, it is under the water’s surface that mangroves really come alive for a marine ecologist like me. (That is also where you start to appreciate red mangroves’ apt name.)

Mangrove roots, both dangling from above (prop roots) and growing up from the sand (pneumatophores), not only mine for nutrients and allow for oxygen and carbon dioxide exchange for the plant; they also provide apparently crucial food and refuge for a stunning array of marine species. Fish, worms, crabs, shrimp, barnacles, and many other organisms take shelter among the roots – gluing right to the wood, hiding in crevices, and peering out through the maze. In such harsh intertidal conditions, where waves break, salt builds up, and the sun beats down, the shade and nooks formed by mangroves may be the key to survival for juvenile fish and crustaceans that will someday populate coral reefs and fishing hotspots farther offshore.

Over the coming months, I will be investigating how and why young fish and crustaceans use mangroves and marshes. By understanding the refuge provided by these very different coastal plants, I hope to better understand how the northward march of mangroves will influence the survival, abundance, and composition of marine species utilizing these now changing coastal nurseries.

Juvenile fish and crustaceans find safety in red mangrove roots during the early, vulnerable stages of their life. This young barracuda may be looking for a snack while hiding from larger predators. (Cora Johnston)

Even mangrove tree crabs that spend most of their time foraging in the canopy climb down to the safety of the mangrove roots to shed their old exoskeletons and harden their new ones. (Cora Johnston)

-Cora Johnston is a PhD student at the University of Maryland. This material is based upon work supported by the National Science Foundation under Grant Number 1065098. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.

Mangrove Tracking VII: Just Another Day at the Office

Monday, July 16th, 2012

by Nancy Shipley

Technician Lorae Simpson and intern Jake Bodart deep in the mangroves, assessing vegetation cover and substrate color. (Mayda Nathan)

It sometimes seems crazy to be climbing through mangrove stands and wading through large ponds to collect our data, but the sites we explore are chosen for a reason. That reason is two-fold: One, to ground truth satellite imagery so we can map historic and current mangrove distributions. Two, to document the plant communities in places dominated by mangroves, in places where mangrove encroachment is occurring, and in places where mangroves have not yet arrived.

By using satellite imagery from years past, we hope to determine how far mangrove communities have spread in the last few decades. To do this we have to first understand what individual plant species comprise the large areas of vegetation that we can see from the satellites.

That is where we come in, climbing through mangroves.

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Posted in Climate Change, Ecology, Grants, Interns, Invasive Species, Mangrove Tracking: Letters from the Field | Comments Off on Mangrove Tracking VII: Just Another Day at the Office

Mangrove Tracking V: A Maverick Crab

Wednesday, June 27th, 2012

Mayda Nathan/University of Maryland

Today we spotted a mangrove tree crab (Aratus pisonii) enjoying nectar from a black mangrove flower. It was surprising enough to find Aratus all over these black mangroves, at the very northern edge of the mangrove range in Florida; it was even more astonishing to see this one’s very un-crablike behavior! Aratus are known omnivores – consumers of mangrove leaves, propagules, insects, even other Aratus – but we’ve never thought of them as floral visitors. They are normally extremely shy, but this particular Aratus was so blissed out by its sugary meal that it didn’t mind (or notice) as we snapped pictures and gawked.

–Mayda Nathan, graduate student (University of Maryland)

This material is based upon work supported by the National Science Foundation under Grant Number 1065098. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.

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Shorelines

Life and science at the Smithsonian Environmental Research Center

Invasive Species

...now browsing by category

From the Field: Arriving in Panama

From the Field: Game Plan for Panama

From the Field: Hunting for Parasites

Climate Change Stimulates Growth of Invasive “Super Weed”

Boaters: Beware of Hitchikers on the Hull

Undersea Parasite Impregnates Crabs, Male and Female

Mangrove Tracking IX: To Catch a Tree Crab

Mangrove Tracking VIII: Beneath the Waves

Mangrove Tracking VII: Just Another Day at the Office

Mangrove Tracking V: A Maverick Crab