Shorelines

by Chris Patrick

Rob Aguilar operates on a cownose ray. (SERC)

It’s 2 a.m. Rob Aguilar, biologist in the Smithsonian Environmental Research Center’s (SERC) Fish and Invertebrate Ecology Lab, meets a group of fishermen at a pound net in the Patuxent River. The net starts at the shore and juts far into the river. Fish traveling along the shore collide with the net and follow its length into a heart-shaped net at the end—the pound.

Today, the pound contains cownose rays. Not ideal for fishermen, but exactly what Aguilar wants. Last summer SERC researchers and collaborators surgically implanted acoustic tags in 31 rays to track their migration. This summer, they’re tagging 20 to 25 more rays from Maryland rivers.

Though native to the East and Gulf Coasts, much about cownose rays remains mysterious. Many fishermen and oyster growers consider rays a nuisance because they eat shellfish and travel in schools in the hundreds.

“The main conflict seems to be between guys who fish for oysters—especially aquaculture oysters because there’s a lot of money in that—and these rays they perceive as potentially eating up their profits,” says Matthew Ogburn, ecologist in the Fish and Invertebrate Ecology Lab. Click to continue »

Eric Hazelton in a Phragmites patch on the Nanjemoy River in Maryland. (Rebekah Downard of Utah State University)

by Chris Patrick

On crime scene investigation shows, DNA forensic scientists sit in a darkened room, wearing lab coats and clutching clear vials over dramatic music. In a matter of hours, they conjure perpetrators to the scene of a crime or prove relations between separated kin simply from remnants of genetic material.

Researchers in the Plant Ecology and Molecular Ecology Labs at the Smithsonian Environmental Research Center (SERC) published a paper in July in Wetlands that has more in common with a CSI episode than you’d expect—though in their case, the process took months instead of hours.

There’s a strain of Phragmites australis, the common reed, that’s native to North America. But the population of an invasive strain from Europe, introduced in the 1800s, suddenly boomed without warning in wetlands around the Chesapeake Bay in the 1980s. SERC scientists had some ideas about what might have caused the sudden explosion, so the team attempted to recreate the history of this sudden, aggressive invasion to test their theories. Click to continue »

by Chris Patrick

Red Lionfish. (Jacek Madejski)

The lionfish (Pterois volitans) resembles a psychedelic fish-shaped peppermint, striped in red and white and decked with feathery, fan-like fins. But its venomous spines and invasive-species status make it much less innocuous than candy.

Lionfish are native to the Indo-Pacific. They’re popular aquarium fish—it’s likely ex-aquarium-owners introduced them into the Atlantic. They spread rapidly along the southeastern coast of the United States, into the Gulf of Mexico and the Caribbean.

Lionfish flourish in their introduced range, where they have no predators. They breed quickly—a female can produce up to two million eggs per year. They live a long time, sometimes more than 15 years. And they’ll eat basically anything that fits into their mouths, decimating populations of native marine animals with their voracious, indiscriminate appetites. When they arrive at a reef, they can reduce the number of native fish by 80 percent.

But lionfish may also be harmful to the native fish they can’t eat. A recently published PLOS ONE study reports that invasive lionfish are parasitized less than native fish. Click to continue »

by Chris Patrick

Lovers of both the Smithsonian and the selfie stick, rejoice! Though the infamous monopods are banned in Smithsonian museums and galleries, they’ve found a new arena of use: labs.

Well, in one lab at least. Researchers in the marine ecology lab at the Smithsonian Environmental Research Center (SERC) are using selfie sticks to record fish behavior without scaring them. SERC’s marine ecology team wants to see if fish raised in low-oxygen conditions acclimate to breathing less oxygen. “I have never heard of someone else using the selfie stick for science,” said Seth Miller, a postdoctoral fellow in the marine ecology lab and collaborator on the project. “Although it probably occurs. Ecologists are pretty resourceful.”

Ashley Collier records a fish without scaring it by using a selfie stick. (Chris Patrick)

Click to continue »

Interns Julianne Rolf and Emily Bulger. (Chris Patrick)

by Chris Patrick

When 11 Smithsonian Environmental Research Center interns piled into a van headed for the Oyster Olympics, they had no idea what was in store. For the next three hours, they shoveled, scooped, scraped, sweated, poured, piled, folded, clamped, ran, and acquired minor injuries competing against interns from other environmental organizations in the area. Though the Chesapeake Bay Foundation (CBF) holds the Oyster Olympics annually at its Discovery Village in Shady Side, Md., this was the first year SERC interns vied for the golden oysters (think of gold-painted shells hanging from rope). From the get-go, it was clear SERC interns were the underdogs. Click to continue »