Monday, September 19, 2022
Off the coast of Belize is a small island the size of a postage stamp called Carrie Bow Cay. There, the Smithsonian Institution’s Coral Reef Ecosystems Program provides opportunities for UNCW students and teachers to further their cutting-edge research on sea sponges and how they affect the overall health of coral reefs.
An interdepartmental team of seven people representing UNCW Marine Science Center and the departments of Biology and marine biology; Chemistry and Biochemistry; and Earth and Ocean Sciences will undertake an expedition next spring to collect samples of sponges and water from the Mesoamerican Caribbean Barrier Reef next to Carrie Bow Cay.
The research, federally funded through a new nearly $1 million National Science Foundation grant, is at the forefront of exploring coral reef ecology. UNCW scientists want to learn more about the effects sea sponges have on their environment as they deal with the large volumes of seawater they pump every day.
“This work represents cutting-edge research to answer fundamental, yet unknown, questions about the functioning of reef ecosystems, which are critical for biodiversity,” said Dr. Ken Halanych, executive director of the Center for Marine Science at the UNCW. “One of the novel aspects of this grant is that scientists from several different disciplines come together to approach the same problem from several different angles.”
The principal investigator, Dr. Wendy Strangman, assistant professor of chemistry and biochemistry, and her team, Dr. Joe Pawlik, professor emeritus of biology and marine biology; Dr. Winifred Johnson, assistant professor of chemistry and biochemistry; and Dr. Ralph Mead, Professor of Earth and Ocean Sciences; collaborated on the research proposal, “The role of sponges in modifying seawater DOMs on Caribbean reefs.”
“It’s really cutting-edge research,” Dr. Strangman said. “With state-of-the-art computing and technology supported by the university, our UNCW team is at the forefront of research in this area. We are delighted that the NSF has the high standard of science performed at UNCW.
This newly funded research is the next phase of ongoing work by Dr. Strangman, Dr. Pawlik and the rest of the team to learn more about what is going on in the coral reef ecosystem at the most fundamental level.
“We know that sponges invade the reef as coral health declines,” Dr Strangman said. “Caribbean reefs of the future are likely to be dominated by sponges, so we are now trying to understand their impact on nutrition in the seawater around the reefs.”
The team will collect water samples before and after they are treated by the sponges and return the samples to the CMS Laboratories to learn more about the dissolved compounds that sponges absorb and their effects on nutrients and other chemicals in the water column.
Dr. Pawlik compares these dissolved compounds to sugar added to a hot cup of coffee. The sugar dissolves; however, the compound still exists in the liquid and can be taken in as food, measured and analyzed. In previous studies, Dr. Pawlik’s students determined that most of the diet of giant barrel sponges on Caribbean reefs is composed of dissolved compounds, but the identity of these compounds remains largely unknown.
“Any information we can gather about the identity of these compounds will be new information for science,” said Dr Pawlik, one of the world’s foremost sponge ecologists. “Until recently, we didn’t have the techniques to answer these questions.”
The team will also develop an outreach component of the project that will share its marine science knowledge with Wilmington community groups such as UNCW MarineQuest summer programs.
“The investigators of this proposal all recognize the importance of giving back to the community and helping to foster the next generation. So they have partnered with MarineQuest, which has excelled in outreach for over 40 years, to develop exciting new modules to stimulate interest in marine systems and their evolution,” added Dr. Halanych.
Each of the four investigators brings a different set of skills to the project. For example, Dr. Strangman specializes in the isolation and identification of more complex dissolved compounds in the seawater mixture, while Dr. Johnson uses new techniques to quantify simpler compounds that may play the role most important as food for sponges and other members of the reef environment.
Researchers will also study the role of seaweed, or seaweed, on the reef. Algae produce a complex mixture of dissolved compounds, and researchers want to determine the role of sponges in removing these compounds when they pump seawater from reefs.
Previously, Lauren Olinger, Ph.D. student working for five years in both Drs. Strangman and Pawlik’s labs discovered for the first time that sponges can absorb compounds called organohalides, often made by bacteria and algae. Organohalides include the elements chlorine and bromine, and many of these compounds are toxic. The team will continue to rely on Olinger’s Groundbreaking Research to better identify these compounds and their origin.
“I’m excited to see this research expanding to our newest collaborators,” Olinger said. “I’m also looking forward to transitioning from being a student to being part of this team as a mentor for future graduates and post-docs. Few students are part of a team that crosses departments. Moving from chemistry to oceanology and biology is challenging, but also very interesting and insightful.
“The UNCW team’s Caribbean sponge research stands out as a collaborative project led by students and faculty experts across multiple academic disciplines,” said Stuart Borrett, vice provost for research and innovation. “One of the best ways to uncover new knowledge is to approach existing questions from multiple angles. This project will help us better understand our oceans, the systems they contain, and the human impact on these systems.
While on Carrie Bow Cay, the research team will live in breathtaking but primitive conditions – an open-air cabin equipped with 4-inch mattresses on planks, a basic roof and the option of a compost toilet or an outhouse at the end of a small dock. Common sights during their two-week stay will be sea turtles nesting on the beach, fist-sized land hermit crabs that form a living carpet on the sand at night, numerous sharks that regularly clash with divers as they work underwater and unforgettable views. of some of the most pristine reefs in the Caribbean.
“Once back to CMS labs at UNCW, then the real work begins: running samples through our analytical instruments and diving into the data we generate to turn it into information we can use,” said Dr. Strangman.
Dr. Ralph Mead, Dr. Wendy Strangman, Dr. Joseph Pawlik, Lauren Olinger, and Dr. Winifred Johnson are collaborating to learn more about sea sponges with an NSF grant. PHOTO BY: JEFF JANOWSKI/UNCW
UNCW Ph.D. student Lauren Olinger (L) is working with Dr. Wendy Strangman to help demonstrate that organic compounds are retained as sponge food, and some of those compounds are organohalides, a class that incorporates the elements chlorine and bromine. PHOTO BY: JEFF JANOWSKI/UNCW