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Two New Bryozoan Species Discovered Off Portugal

Tuesday, March 10th, 2015

by Kristen Minogue

Image: SERC research associate and Portuguese native João Canning-Clode. (Credit: Valentyna Chan)

SERC research associate and Portuguese native João Canning-Clode. (Valentyna Chan)

Since he began surveying the waters of Madeira two years ago, João Canning-Clode has discovered a new invasive species almost every month. The archipelago off the coast of Portugal is a hot spot for biodiversity, especially for bryozoans – “moss animals” that often cover rocks, piers and other artificial substrates. But he didn’t anticipate finding a completely new species, let alone two.

Bryozoans are easy to mistake for plants or corals from a distance. Some resemble moss as they form encrusting colonies on underwater rocks. Others form branching, bush-like colonies that look more like algae or corals. Up close, though, a single colony can contain millions of individual, tube-shaped zooids. The zooids support each other. But break a piece off, and a single zooid can start a new colony of its own.

The team named the new species Favosipora purpurea (for its pinkish-purple color) and Rhynchozoon papuliferum (for its special triangular-shaped zooids). In this Q&A, Canning-Clode, a research associate with the Smithsonian Environmental Research Center, details the dual discovery published this month.

FavasiporaPurpurea_PatricioRamalhosa

 Rhynchozoon_papuliferum_Web
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Oyster Disease Thrives in Nightly Dead Zones

Wednesday, February 11th, 2015

by Kristen Minogue

Image: Slides of oysters suffering different Dermo intensities as the parasite multiplies, from healthy (left) to severely infected (right). (Credit: SERC Marine Ecology Lab)

Slides of oysters suffering different Dermo intensities as the parasite multiplies, from healthy (left) to severely infected (right). (SERC Marine Ecology Lab)

In shallow waters around the world, where nutrient pollution runs high, oxygen levels can plummet to nearly zero at night. Oysters living in these zones are far more likely to pick up the lethal Dermo disease, a team of scientists from the Smithsonian Environmental Research Center discovered in a new study published Wednesday.

Oxygen loss in the shallows is a global phenomenon, but it is not nearly as well known as the dead zones of the deep. Unlike deep-water dead zones, which can persist for months, oxygen in shallow waters swings in day-night cycles, called diel-cycling hypoxia. In nature it works like this: When algae photosynthesize during the day, they release oxygen into the water. But at night, when photosynthesis stops, plants and animals continue to respire and take oxygen from the water, causing dissolved oxygen to drop. Nutrient pollution, because it fuels massive algal blooms, can make the cycle even more drastic. The resulting lack of oxygen can cripple the oysters’ ability to fight off the parasite Perkinsus marinus that causes Dermo and slowly takes over their bodies.

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Four Invaders That Seduced Us (And One
That Could)

Thursday, January 29th, 2015

by Kristen Minogue

Image: School of blue-green damselfish (Chromis viridis) in the Coral Sea (Credit: Richard Ling)

School of blue-green damselfish, Chromis viridis, in the Coral Sea (Richard Ling)

You could be forgiven if, on the long list of environmental threats, the site of an empty aquarium doesn’t fill you with dread.

Most invasive species cross our borders by accident, stuffed into crates with packing material, or clinging to the hulls or floating in the ballast of cargo ships. Often we don’t even realize they’re here until years after they arrive. But there are a few that we welcome into our homes (or fish tanks) with open arms, because they are beautiful and exotic and, well, we’re human. Sometimes they’re harmless, and sometimes our infatuation has deadly consequences.

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2014 in Review: The Good, the Scary and the Weird

Wednesday, December 31st, 2014
Photo: Dejeanne Doublet inspects a red oak in BiodiversiTree. (Credit: SERC)

Dejeanne Doublet inspects a red oak in BiodiversiTree. (SERC)

by Kristen Minogue

We sprayed pig’s blood on baby trees, studied a strange ménage a trois in the orchid world and met the father of marine invasions science himself. It’s been an odd year at the Smithsonian Environmental Research Center. But we like living in interesting times. Here are 10 of our favorite stories from 2014. Here’s hoping 2015 is even stranger.

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Dead Zones Likely to Expand as Coastal Waters Warm

Monday, November 10th, 2014

by Kristen Minogue

Image: Menhaden fish kill in Narragansett Bay, Rhode Island. (Credit: Chris Deacutis)

Menhaden fish kill in Narragansett Bay, Rhode Island. (Chris Deacutis)

A full 94 percent of the world’s dead zones lie in regions expected to warm at least 2 degrees Celsius by the century’s end according to a new report from the Smithsonian Tropical Research Institute and the Smithsonian Environmental Research Center published Nov. 10 in Global Change Biology. The paper states that warmer waters—mixed with other climate change factors—make for a dangerous cocktail that can expand dead zones.

Dead zones form in waters where oxygen plummets to levels too low for fish, crabs or other animals to survive. In deeper waters, dead zones may last for months, as with the annual summer dead zone in the Chesapeake Bay. Temporary dead zones may occur in shallow waters at night. The largest dead zones in the Gulf of Mexico and Baltic Sea can cover more than 20,000 square miles of the sea floor. The number of dead zones across the world is growing exponentially, doubling each decade since the 1960s.

“They’re having a big impact on life in the coastal zone worldwide,” said Keryn Gedan, a co-author and marine ecologist at the Smithsonian Environmental Research Center and the University of Maryland. “A lot of people live on the coast, and they’re experiencing more fish kills and more harmful algal blooms. These are effects of dead zones that have an impact on our lives.”

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Oysters and the Chesapeake’s Jellyfish Wars

Tuesday, September 30th, 2014

Image: Jellyfish Chrysaora quinquecirrha (Credit: Lori Davias)

Jellyfish Chrysaora quinquecirrha (Lori Davias)

by Kristen Minogue

Every summer, the food web in Chesapeake Bay gets jostled around as two plankton-eating predators jockey for power: comb jellies and jellyfish. Most smaller species don’t have a stake in the battle—both predators eat zooplankton and fish eggs, after all. But for young oyster larvae, the victor could make the difference between being protected civilians or collateral damage.

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Why 900 Years of Ancient Oysters Went Missing

Friday, August 29th, 2014

by Kristen Minogue

Piscataway Indians lived on the Rhode River up to colonial times, though anthropologists believe they used the land for temporary campsites, not permanent settlements.

Piscataway Indians lived on the Rhode River up to colonial times, though anthropologists believe they used the land for temporary campsites, not permanent settlements.

For more than 10,000 years, Native Americans hunted and fished in the Chesapeake. Broken pottery, village sites, burial grounds and other artifacts bear witness to their near-continuous presence around the Bay. But one type of artifact—ancient trash piles called shell middens—hasn’t received as much attention. And these tell another important story.

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SERC camps cultivate environmentally-conscious kids

Tuesday, July 29th, 2014

By Sarah Hansen

"Who's been seining before?" asks Anna Youngk, SERC education intern and camp counselor.

“Who’s been seining before?” asks SERC education intern Anna Youngk (right).

“Hurry, hurry, hurry!  Baby pipefish!” camper Jack Yee, 11, squeals as he trundles across the beach in much-too-big waders with hands cupped.  A moment later the startled fish, caught by campers in a seine net, is swimming safely in a plastic tub already populated with silversides, glass shrimp, and one large pickerel.

XXXX (left) and Jack Yee are ready to dissect a perch.

Orion Ford, 10 (left), and Jack Yee, 11, are ready to dissect a perch.

Jack’s energy and concern for the creatures of Chesapeake Bay are exactly what SERC summer day camps are all about.  The programs range from “Pollywogs” camp for prekindergarten students to this week’s offering, “Environmental Detectives” camp for rising fifth- and sixth-graders.  Led by Education Department interns Anna Youngk, Lizzie DeRycke and Eric Glass, each week 12 children experience activities related to the Bay, its inhabitants, and what they can do to help. Click to continue »

Oysters have sidekick in Chesapeake Bay clean-up

Friday, July 25th, 2014

By Sarah Hansen

Keryn Gedan collects mussels and oysters "by the handful" for her research. (Keryn Gedan)

Keryn Gedan collects mussels and oysters “by the handful” for her research. (Chris Judy)

Oyster restoration has long been championed as key to cleaning up Chesapeake Bay, because oysters’ filter-feeding lifestyle improves water quality by removing plankton.  But oysters aren’t the only ones that can do the job.  A new study reports that another bivalve, the hooked mussel, also removes its share of plankton from the clogged Bay. Click to continue »

Blue Crabs Need (More Than) A Few Good Men

Thursday, July 24th, 2014

by Kristen Minogue

Photo: Male blue crabs can mate with multiple females. But with fewer men to go around, their female partners are left with less sperm to reproduce. (Credit: SERC)

Male blue crabs can mate with multiple females. But with fewer men to go around, their female partners are left with less sperm to reproduce. (SERC)

The practice of selectively fishing male blue crabs in the Chesapeake—intended to give females a chance to reproduce—may have a hidden cost. A Bay without enough males could reduce the number of offspring females produce, ecologists at the Smithsonian Environmental Research Center found in a paper published in the July issue of Marine Ecology Progress Series.

Maryland and Virginia began reducing the harvest of female crabs by commercial and recreational watermen in 2008, the year officials declared the blue crab fishery a federal disaster. Since then, the crabs have shown signs of a shaky recovery. But a lasting comeback hinges on females producing enough offspring to sustain the population.

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