Rhode Island State Coral Poised to Show Way Forward in Era of Climate Change
July 1, 2021
When both chambers of the General Assembly passed bills June 8 declaring the northern star coral as the state’s official coral, it made Rhode Island the first state to designate a state coral. And while the Ocean State is not known for its corals, advocates say that’s one reason they pushed for the moniker.
“People are often surprised to hear that there’s a coral that lives off the coast of Rhode Island,” said Koty Sharp, associate professor of biology at Roger Williams University, who proposed the idea for a state coral. “It’s part of our coastal ecosystem, and it’s a very charismatic organism. Under a microscope, people are always impressed with how beautiful it is.
“If we can show this to more people, especially schoolchildren, we can engage them with their local ecosystem and educate them about what’s out there. The more we do that, the more we can expect the next generation to act for conservation and keep our environment as a top priority.”
Choosing which coral to designate wasn’t difficult. Northern star coral (Astrangia poculata) is the only hard coral found in New England waters. Unlike the large, familiar corals that grow in warm-water regions like Florida and the Caribbean, this brown or white coral can fit in the palm of one’s hand and is often mistaken for an anemone, with a fleshy stalk and long tentacles.
“It’s very different from its tropical cousins in many ways,” Sharp said. “That’s what makes it so special. It’s different. It’s much hardier, so it can withstand extremely cold winters and very hot summers.”
The most significant difference, she said, is northern star coral doesn’t rely on a symbiotic relationship with algae, which tropical corals use to make sugars to survive. Rhode Island’s coral doesn’t require that partnership to eat. Instead, it uses its tentacles to capture food in the seawater.
Northern star coral is typically found in water 5-30 feet deep, though it has been documented more than 90 feet deep. Its range extends from Buzzard’s Bay in Massachusetts to the Gulf of Mexico, but it’s also found throughout the Caribbean and off the coast of South America and West Africa.
“It’s fairly abundant here in Rhode Island, much easier to find here in the shallows of our coastline than in Florida,” Sharp said. “We think that’s because this organism evolved to thrive in habitats that have large seasonal fluctuations — cold winters and hot summers. The tropics don’t experience those kinds of variations in temperatures. Tropical corals aren’t very resilient to those kind of changes.”
According to Sharp, the northern star coral was first described in the late 1700s from specimens collected off Newport. A retired oceanography professor at the University of Rhode Island, Michael Pilson, laid the foundation for detailed studies of the species in the 1970s and ’80s, and Sharp has been studying its ecology and physiology for the past 10 years.
Because of the coral’s hardiness in varying temperatures, Sharp calls the northern star coral a model organism for understanding corals and what can be done to help them survive in the face of the climate crisis. She is especially interested in the microbes that live on the surface of the coral and play a role in its ability to respond to and recover from a changing climate.
“We’re studying that to learn more about Astrangia in the Rhode Island ecosystem, but also using it to extend into the microbiology of tropical corals,” Sharp said. “One thing that has become very clear in the past several years is that the microbes that live on the surface of tropical corals are extremely important for their responses to environmental disturbance. It’s their first line of defense against microbial pathogens, infections and disease. Just like what we know about the human gut, the microbiome structure is critically important for regulating the health of the host animal.”
Sharp’s research has expanded in recent years as more and more scientists have become interested in studying the northern star coral. What started as a group of 15 researchers has grown to more than 120 who meet each year at Roger Williams University. It was at one of those meetings, when the scientists discussed how to elevate the public’s awareness of the northern star coral, that the idea of a state coral was first discussed.
The legislation (H5415, S0067) designating Rhode Island’s state coral was sponsored by two Portsmouth lawmakers, Rep. Terri Cortvriend and Sen. James Seveney, who introduced it to call attention to Sharp’s research at Roger Williams University.
“Species like the northern star coral can be a bellwether that shows us where we are headed if we continue to abuse and pollute the earth. We should pay attention to it,” Cortvriend said. “While the bill is somewhat lighthearted and fun, what I really hope is that it starts more conversations about why we cannot wait to address our climate-change crisis. These tiny polyps have a lot to tell us about what we’re doing to our planet, and designating them our state coral can amplify that message.”
The legislation has already energized Sharp and her fellow coral researchers. “Our research community is completely buoyed by this,” she said.
Now that the state coral designation is official, Sharp looks forward to using it as a platform for a number of projects, including a K-12 Science, Technology, Engineering and Math (STEM) curriculum focused on climate literacy.
“Astrangia is a great emblem for the state of Rhode Island because it’s small like Rhode Island, it’s hardy like Rhode Islanders, and it’s positioned to provide insight to solve global problems,” Sharp said.