NPS projects seek to stabilize shoreline, regrow coral reefs and mangroves
By ANDREA MILAM St. John Correspondent, Daily News, Oct 19, 2022
Even before the devastating hurricane season of 2017, St. John’s ecosystems were in trouble.
“There were a number of concerns even before the storms of impacts both natural and caused by humans to these three systems — shorelines, mangroves, and corals,” said Virgin Islands National Park Superintendent Nigel Fields. “Clearly, Irma and Maria gave us an opportunity to better understand those systems as a whole and their interactions. Even though we’re looking at these as distinct projects, we’re keeping our view on the whole system.”
Each of these interconnected ecosystems is being approached by teams of NPS personnel and federal and local partners.
“This kind of approach at this scale hadn’t occurred before,” said VINP Chief of Resource Management Thomas Kelley. “The idea of splitting up into groups made it more meaningful and manageable, to have a nimble team of experts focused on each of the areas.”
Even though the stress and damage caused by the 2017 hurricanes potentially opened the door for Stony Coral Tissue Loss Disease to spread quickly through territory reefs, corals were already in trouble when Irma and Maria hit, in part due to the sustained bleaching event that killed 59 percent of hard corals in 2005-2006, said Kelley. At least 12 diseases affect local reefs, Kelley added.
With Stony Coral Tissue Loss Disease posing the most urgent threat, this challenge is being faced head-on with a multipronged approach. VINP has teamed up with the University of the Virgin Islands, Coral World, and CORE, while sister parks in St. Croix are partnering with The Nature Conservancy to address treatment of affected corals and growth and outplanting of new corals to help recover what’s been lost.
The VINP considered 34 sites around the island for the outplanting of nursery-grown corals before selecting the Annaberg shoreline.
“We’re going to establish a small in-water coral nursery in about 20 feet of water near the trail head to Leinster Bay,” said Kelley, who added that the project is being undertaken by CORE in partnership with Friends of VINP and support from NPS and other partners. “One reason is to provide outreach education to the community, visitors, and schoolchildren.”
In addition to taking active measures to help sustain the local coral population, the VINP hosts visiting scientists in the hopes of learning more about current threats to coral reefs.
“We know that 80% of the corals that are most highly susceptible to Stony Coral Tissue Loss Disease are potentially lost,” said Kelley. “We’re looking at the 20% that make it to learn what may be special about their makeup that allows them not to catch the disease. There’s been a large amount of research and many studies and we have yet to even identify a causative agent, whether it’s a virus or a bacterium.”
Woods Hole Oceanographic Institute is currently engaged in three studies involving reefs in the VINP, and California State University-Northridge has three active permits for studies within the park, including an ongoing study now in its 34th year monitoring soft corals. The university is also partnering with Woods Hole to look at coral symbionts, like microfauna, which are associated with coral at the tissue level, which may play a role in the spread of disease.
“If we understand the mechanisms of disease we can help with treatment,” said Fields. “This collaboration of scientists helps us better advance the knowledge. That’s why partnerships are so key. They help us answer the big questions.”
The reasoning behind devoting resources to the restoration of coral reefs in the territory has several components, Fields continued.
“One of the reasons is the role of the reefs in stabilizing our fisheries here,” said the VINP superintendent. “Reefs are a key part of that system, which many people depend on. Reefs are also part of our tourism economy, and they’re also tied to ways of life here. Equally as important is the role reefs play in protecting our shorelines. Reefs are the first barrier and they do a lot to protect us from major storm surges.”
Tying together the reefs and the shoreline are mangroves, which trap and filter out sediments that can harm coral reefs. The VINP has set its sights on the mangrove forest at Annaberg, which was formerly one of the largest, most well-established of its kind on St. John. These mangroves were decimated during hurricanes Irma and Maria, and they’ve struggled to bounce back due to a lack of hydrological exchange between the forest and the ocean, which are separated by the road leading to the Annaberg plantation ruins. The VINP restored hydrology via previously established culverts, which were effectively sealed off by sediment and debris due in large part to the hurricanes. The park service is partnering with Iowa State University, which is growing around 600 mangrove species at its garden at Gifft Hill School.
“They were a perfect partner to fund to have them grow the plants and ultimately, with assistance from the Friends, outplant the mangroves a couple months from now,” said Kelley.
Test plots at the Annaberg mangroves have had nearly 100% survivability, Kelley added.
Scientific study focusing on mangroves is set to begin in 2024 in the Hurricane Hole area, where the relationship between corals and mangrove prop roots is one of the most unique and diverse in the world.
“This multipark study will take place on St. John and at Salt River in St. Croix,” said Kelley. “We’re partnering with UVI to investigate the role of coral species that interact directly with mangrove systems, particularly the prop roots.”
NPS funding for such studies has been difficult to secure due to fewer monies being available and a higher level of competition with more parks seeking funding, Kelley added.
“We’re taking a lot of work [USGS emeritus scientist] Dr. Caroline Rogers did observing these systems and trying to go to the next step to further understand them,” said Fields. “It’s necessary research that we’re hoping will give us a lot of insight into how these systems interact and what we can do to better protect them.”
Shoreline recovery is also ongoing at Annaberg. To address several feet of road that was lost due to the hurricanes at the Leinster Bay trail head, asphalt was removed and replaced with riprap — rocks placed to protect the shoreline— and the trail head was formalized, making it safer and more accessible.
“It will be a much more aesthetically pleasing access to the Annaberg historic district,” said Kelley.
The VINP is also working to stabilize shorelines in other areas by removing invasive plants like tan tan and sweet lime, replacing them with native plants like seagrapes in partnership with the Friends of VINP. Kelley said the park is aiming to place caging around the new plants once they’re planted on shorelines to protect them from the white-tailed deer, whose eating habits threaten the survivability of young adult plants.
Ultimately, said superintendent Fields, forming partnerships is a necessary part of preserving and protecting the island’s corals, mangroves, and shorelines.
“We’re a partnership park,” he said. “We can’t do it by ourselves. We learn and study and grow with our partners.”