BARRET WESSEL IS A STUDENT OF GOOP.

Right now, he's standing by a narrow stream in Rock Creek Park in Washington, D.C. The waterway, too small to merit a name, "flows into, I think it's Bingham Run and then Rock Creek," Wessel says, referring to the park's namesake. The creek curves through the city before emptying into the Potomac River.

It's July, and Wessel is about a month away from starting his final year of college at the University of Maryland, College Park. This afternoon, he's on the hunt. A fringe of marshy plants borders the stream, and flying insects flit just above the surface of the water. But Wessel, wearing a denim shirt and rubber boots for wading, is looking for something else. He calls it "goop."

"Let's see if we can find some iron flocculate," Wessel says. "There's a little bit right here."

He steps onto wet river rocks and points to an orange film that is growing in a shallow ripple in the stream. This gelatinous material, which looks like someone poured pudding into the creek, is iron flocculate, Wessel explains. It's produced by a certain class of microbes called iron-oxidizing bacteria. You can find these microbes in any stream, but they're particularly common in environments that are rich in iron.

The college student is spending his summer exploring this goop. He's paid regular visits to nine streams in Maryland and the District of Columbia, collecting dozens of water samples and measuring the amount of flocculate growing in the currents. Wessel hopes that his research project will help to answer a few questions about the growth of these bacteria: why, for instance, are iron-oxidizing bacteria more abundant in some creeks than others? His results could inform ongoing research into how scientists and others can restore the health of urban streams that trickle into the Chesapeake Bay.

Wessel is one of 18 students participating during the summer of 2014 in Maryland Sea Grant's Research Experiences for Undergraduates (REU) program. This educational opportunity aims to give undergraduates from across the country an introduction to scientific research: like Wessel, these REU students will spend 12 weeks embedded in a marine science lab in Maryland, learning how to design and conduct their own research study.

Such forays into research can be an important step in a college undergraduate's education. Through this REU program, students like Wessel produce high-quality scientific reports, and gain experience working in a lab — experience that can help to give them an edge when they apply for jobs or graduate schools. But maybe more important, they also receive a first-hand glimpse into what it's like to be a marine scientist.

"It's all part of training the next generation" of scientists, says Jamie Pierson, a biological oceanographer at the Horn Point Laboratory of the University of Maryland Center for Environmental Science (UMCES), who has mentored several REU students over the years. "The rewarding part is seeing them be successful and get excited about science and stay in science."

The students who join this educational experience hail from diverse backgrounds. Wessel, for instance, came to science from a roundabout path. The Maryland native, now 28, signed enlistment papers to join the U.S. Navy when he was still in high school.

After leaving military service because of a knee injury, Wessel worked odd jobs for several years. Then, in his mid-20s, he had an epiphany of sorts. He was working at a used bookstore at the time that took in a big donation of books from the library of a science buff.

"It was just a huge personal collection of math, physics, science books. I read a bunch of them and ended up getting my hands on Carl Sagan's 'Cosmos,'" he says, referring to a TV show that aired in 1980 and a book of the same name that delved into the workings of the universe. "And I was sold."

Soon after, Wessel enrolled in classes at the Howard Community College in Columbia, Maryland, and later transferred to the University of Maryland. During his REU summer, he interned in the lab of Michael Williams, a biochemist at the Chesapeake Biological Laboratory, which is also part of UMCES.

Wessel says he applied to the Maryland Sea Grant REU program because he plans to go to graduate school, either in environmental science or environmental engineering.

It was also just exciting to get outside and do field work, he says. "You get wet and muddy," he says. "You work like a 16- or 20-hour day just to get the samples in the fridge so you can look at them the next day." But, he adds, "It's a lot of fun."

He's not the only student getting in on that fun, either. Maryland Sea Grant's REU program is one of nearly 650 similar educational experiences spread across the United States and funded by the National Science Foundation (NSF). In the Chesapeake Bay region alone, you can find four REU programs in addition to Maryland Sea Grant's that focus on marine research.

They're affiliated with the University of Maryland Eastern Shore in Princess Anne, Maryland, the Smithsonian Environmental Research Center in Edgewater, and the Virginia Institute of Marine Science and Old Dominion University, both in Virginia.

The REU program run by Maryland Sea Grant accepted its first students in 1989 and has operated every year since then. It's selective: Wessel and the 17 other REU students enrolled in the program in 2014 were chosen from around 350 applicants, a typical number for this program.

One of the goals of the national REU program is to spur more women and members of minority groups to pursue careers in science, says Elizabeth Rom, who oversees the NSF's ocean education programs. That's been a constant struggle both in the sciences in general and in ocean science in particular, Rom explains. In 2012, for instance, around 10 percent of the science Ph.D.'s awarded to U.S. citizens or permanent residents went to minority students, according to data collected by the NSF.

Maryland Sea Grant's REU program has worked to increase those numbers. Between 2009 and 2014, 20 out of the 75 participating students came from minority backgrounds. From the start, women have made up around half or more of the program's participants every year. That's a ratio that the field of ocean science as a whole has only recently caught up to.

From the REU Class of 2014:
In Their Own Words

Barret Wessel, University of Maryland, College Park, MD

Jeffrey Rice, Florida Gulf Coast University, FL

Isabel Sanchez, Universidad Metropolitana, PR

Other kinds of diversity are also advanced by the program. Some of the undergraduates come from institutions like Elmhurst College in Illinois that are far from America's coasts and whose students otherwise would have little opportunity to experience marine research firsthand. (See map.) And the program draws most of its participants from small colleges where faculty members do little scientific research of any kind, says Mike Allen, assistant director for research at Maryland Sea Grant.

"I think the REU program is really important for those students," says Hali Kilbourne, a paleoclimatologist at the Chesapeake Biological Lab, who has also mentored REU students.

That's because getting hands-on exposure to real research is a crucial step in an undergraduate's education, says Tom Jones, an estuarine ecologist at Salisbury University in Maryland. Jones has been a mainstay of the Maryland Sea Grant REU program since its start and leads the program's annual orientation program that includes a day-long cruise. During this boat trip on the Chesapeake Bay and Patuxent River, REU students get a crash course in the ecology and history of the estuary — while collecting data relevant to local ecosystems.

Jones notes that too often students in higher education only have the opportunity to learn about science through lectures or staged lab experiments. Without the opportunity to get wet and muddy as Wessel did, many students get turned off by the sciences, switching their majors to other fields. And that's of concern because numerous national reports have argued that America's economy would benefit if its workforce were more scientifically literate.

When it comes to conducting research, "if students don't have the responsibility to do it and get it right in the lab for real," Jones says, they never gain "the confidence that they can do it. They just lean on other people."

To offer these helpful doses of confidence and experience, the Maryland Sea Grant REU program pairs each participating undergraduate with a mentor at one of two marine labs: the Chesapeake Biological Laboratory in Solomons, Maryland, and the Horn Point Laboratory in Cambridge. The students live in dorms on those campuses and receive stipends of $6,000 each. They work with their mentors to pick a topic that they want to study, then carry out a complete research project from start to finish. At the end of the summer, the students write up their research results in a final paper and speak about their work in a talk that's open to the public.

Over the years, Maryland Sea Grant's REU students have spent their summers exploring a wide array of topics that have spanned the entire Chesapeake Bay ecosystem. Some students have dug into the lives of important Bay organisms, like oysters and wetland reeds. Other undergraduates have researched issues that affect the health of the estuary like nutrient runoff from cities and farms and blooms of harmful algae.

Maryland Sea Grant also introduces its interns to some of the less obvious aspects of being a scientist. REU students learn how to write research grants and funding proposals, and they attend a workshop on scientific ethics — topics that take up a lot of a researcher's time but rarely get mentioned in the classroom.

All of these activities make for a busy summer for REU students like Jeffrey Rice. He's an undergrad at Florida Gulf Coast University in Fort Meyers and is interning with Thomas Miller, a fisheries scientist and director of the Chesapeake Biological Laboratory.

Rice is doing his daily rounds in a laboratory that houses dozens of scuttling blue crabs. The crustaceans are young, only a few inches long at this point, and are stored individually in small tanks the size of shoeboxes. If you keep two crabs in the same tank, Rice explains, they'll start to fight — sometimes to the death. "They're jerks," he says, laughing.

This summer, he's learning a lot about these crustacean jerks. In particular, he's trying to unravel the chemical composition of the blue crab exoskeleton.

It may sound like a simple question — what is a crab's shell made of? But it's not one that scientists know the answer to. Crustacean researchers assumed that the shells were built mostly out of calcium carbonate, the main mineral in chalk. Lobsters and some other close cousins of crabs have shells that are 95 percent calcium carbonate by weight. But no one knew whether blue crabs shared that exact make up.

It's a question that's relevant to the Chesapeake Bay. That's because the estuary, like other water bodies around the world, is growing more acidic as a result of increasing levels of carbon dioxide in the atmosphere. This chemical change, called ocean acidification, may affect how some shelled animals build their exoskeletons. Knowing the exact ingredients in a crab's exoskeleton could give scientists clues as to how acidification might alter how crabs form their shells.

To discover this recipe, Rice crushed up bits of shell from both adult and juvenile blue crabs. Then he ran the resulting mash through a machine called a spectrometer that analyzed its chemical ingredients.

The results were surprising. Rice discovered that the exoskeletons of adult blue crabs were only 65 percent calcium carbonate by weight — much less than lobsters.

Why the exoskeletons of blue crabs are so different from those of other crustaceans isn't clear, Rice says. But his findings will inform further research and understanding about the effect of ocean acidification on the Bay's crab populations.

He's not the only REU student whose work has advanced science about the Chesapeake Bay. In many cases, these undergrads have helped to produce research findings that were later published in scientific journals. Maryland Sea Grant's REU students have coauthored 34 scholarly papers with their mentors. More than 70 students, and counting, also presented their research at science conferences both in the United States and abroad.

One of the papers was coauthored by Katharine Smith, an REU student in 2005. She helped to show that breakwaters made from oyster reefs can benefit nearby clumps of underwater grasses in the Chesapeake. The reefs block waves, keeping the water around the plants from getting choppy and cloudy. That was an important finding because these grasses have largely disappeared around the estuary in recent decades. Smith and her mentor, Elizabeth North of the Horn Point Laboratory, published their research in 2009 in the journal Estuaries and Coasts.

Jamie Pierson, the biological oceanographer at Horn Point Laboratory, says that when he takes on an intern, his goal from the start is to give the student a great learning experience. But he also wants them to do something with real results.

"We try to set up a project that will be successful for them and that will move the lab forward," he says.

There are less tangible benefits of REU programs that can't be boiled down to a scientific paper or a resume point. That's because the end of college for students like Rice brings a lot of choices.

"At the undergraduate level, it's really critical for them as juniors and seniors to figure out, first off, 'Am I going to go to grad school, and...do I want to do it in marine science?'" says Tom Jones, the estuarine scientist at Salisbury University.

And many REU students say that the program has helped them to make those exact kinds of decisions.

Here on the Chesapeake Bay, dozens of Maryland Sea Grant's former REU students have gone on to obtain graduate degrees in science fields, according to an ongoing survey of alumni. Of the 177 students who responded to Maryland Sea Grant's queries over the years, 52 had already received or were in the process of getting their Ph.D.s in various fields. A total of 121 were enrolled in or had finished a master's degree program.

The same is true on the national level. In 2007, researchers surveyed thousands of students who had taken part in an REU or another similar educational program about their experiences. About two-thirds of the respondents said that their time doing research increased their interest in going to grad school or working in a science-related field. Simply put, once they whetted their appetite for research, they wanted more.

At the same time, these programs only go so far: about 4,000 students attend one of the NSF-funded REU programs per year. That's a sliver of America's total undergraduate population of 18 million.

Maryland Sea Grant REU students who spent the summer of 2014 on the Bay say the program helped to open their eyes to a variety of possible careers. That includes Isabel Sanchez, one of two students from Puerto Rico who joined the program. She will graduate in 2015 from the Universidad Metropolitana, a four-year university in San Juan. In Maryland, she interned for Pat Glibert, a plankton ecologist at the Horn Point Laboratory.

Sanchez's research focused on the population booms and busts of microscopic algae that live in lagoons off the coast of mainland Virginia. Her research is important for understanding how the runoff from farm fertilizers, which are rich in nutrients like nitrogen, might help to trigger explosive blooms of algae in these ecosystems. Such blooms can pose health risks to people and fish.

She says that because of her experiences in Maryland, she's hoping to attend graduate school in environmental science in the continental United States. Her ultimate plan is to take what she's learned back to Puerto Rico, helping to preserve marine ecosystems on the island.

"All the stuff that I've been learning and doing here has never been done back in Puerto Rico," Sanchez says.

A Good Start to
Their Careers

MARYLAND SEA GRANT'S REU STUDENTS have gone on to contribute to the field of marine science, following diverse career paths both nationally and on the Chesapeake Bay. Read about the current professional lives of three REU alumni: Cynthia Suchman ('89), Carlos Lozano ('05), and Jeannette Davis ('06).  more . . .

Emily Maung-Douglass made a lot of decisions, both professional and personal, while she was an REU student. She spent the summer of 2003 at the Chesapeake Biological Laboratory studying marine bacterial diversity. She said she was taken by the adventure of living at a marine lab tucked away from most of the world and working odd hours as needed to complete research.

"It was kind of a romantic thing to be the scientist in the middle of the night coming into the lab," Maung-Douglass says.

So she earned her Ph.D. in marine biosciences at another quiet marine lab — this one at the Lewes campus of the University of Delaware. Now at Louisiana Sea Grant, which is based in Baton Rouge, Emily is an outreach specialist helping to educate the public about new research findings regarding the Deepwater Horizon oil spill.

Maung-Douglass met her future husband, Keith Douglass, in Solomons that summer, too. He was an REU student that same year. For a recent anniversary, the couple traveled back to Solomons and strolled past the buildings where they lived and worked years before.

Her REU internship "was just one of the best experiences of my life," Maung-Douglass says. "It really made me grow creatively as a scientist. And it made me brave enough to try to live at other marine labs."