Fisheries

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From the Field: Finding Oysters in Panama

Friday, December 14th, 2012

by Katrina Lohan

Katrina Lohan, attempting to scrape oysters off a rock at Punta Culebra, Panama. (Kristy Hill)

I would love to be able to say that I am a world traveler with loads of experience visiting other countries, but that would be far from the truth. Unfortunately for me, my passport has only a few stamps. (Two to be precise, as it wasn’t stamped for walking across the border into Mexico or crossing the border to have dinner in Canada.) So traveling to Panama to collect oysters has expanded my horizons in more ways than one!

In Panama, Kristy and I are working with Mark Torchin and Carmen Schloeder, scientists at the Smithsonian Tropical Research Institute in Panama. Our first sampling site was about a five-minute drive from the Smithsonian’s Naos Laboratory, which sits just outside Panama City on the Pacific Ocean.

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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!

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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Nightly Oxygen Drops Deadly
for Chesapeake Oysters

Tuesday, September 25th, 2012

by Kristen Minogue

Slide of an oyster completely infected with Dermo.


Oysters in Chesapeake Bay face more dangers than overfishing and habitat loss. Over the last few decades they’ve also had to contend with crippling disease outbreaks. And according to marine ecologist Denise Breitburg, the wild day-night fluctuations in Bay waters aren’t helping.

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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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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.


More stories from the mangroves >>

Chesapeake Blue Crabs: The Shaky Recovery

Wednesday, June 13th, 2012

by Tuck Hines

Smithsonian Environmental Research Center


Few creatures in Chesapeake Bay have experienced the kind of whiplash felt by the blue crab. Having gone through a near-disastrous decline that lasted almost two decades, they made a dramatic comeback starting in 2009. But before managers could proclaim it a success, the numbers fell again. And this time, the reasons aren’t so clear.

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Toughest Shellfish in the Sea?

Tuesday, January 24th, 2012

by Kristen Minogue

Blue mussels (Credit: Meriseal)

Some species can survive just about anywhere. Take blue mussels, a group of shellfish whose habitat stretches from the Arctic to the Mediterranean. Over the last several decades, biologists have thrown all kinds of tests at them – heat, cold, saltwater, freshwater, low oxygen. They’ve even tried drying them out. Almost nothing fazes these animals. For invasion scientists trying to figure out how far they could spread, that’s a scary prospect.
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Six Endangered Species of the Chesapeake

Wednesday, November 23rd, 2011

by Kristen Minogue

Bat infected with deadly white-nose syndrome.
(U.S. Fish and Wildlife Service)

The last Western Black Rhino appeared in Cameroon in 2000. Now they’re gone, according to the International Union for Conservation of Nature, which declared the rare subspecies officially extinct Nov. 10. As thousands more species go extinct across the world every year, the Chesapeake Bay watershed is fighting to save its own endangered flora and fauna. Maryland counts 362 plants and animals on its endangered list – and that’s not including the ones that have already been wiped out from the state. Whales, bats, turtles and orchids: here are six of Chesapeake’s most wanted.
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