Fresh into 2026, Krista McCoy, Ph.D., walks past crowds of tourists enjoying demonstrations of aquatic life at the Florida Oceanographic Society facility in Stuart, where she has worked as its director of research and conservation since September 2024.
Her years of research documented how the Indian River Lagoon fell prey to a bevy of toxins – from effluent leaked by aging septic systems to pesticides carried downstream from farmland – that influenced algal blooms and mass mortalities.
Today, however, her work carries a glimmer of hope on the genetic level that she and other researchers could use to produce hardier grasses and other organisms in the lagoon and local waters.
Her routine includes interacting with tanks of seagrass in an “experimental meadow” not far from the museum grounds, she said in a Jan. 2 interview. Some grasses bore strings of algae across their stalks indicative of rot. Others looked hardier, with longer stems of a greener hue indicating greater chlorophyll content clear of algae.
The latter seagrass patches displayed traits that could lead to counteracting mass mortalities among plants and animals in the Indian River Lagoon and other East Coast waterways alike through an “intentional” approach “about restoration,” McCoy said.
McCoy and her colleagues intend to present their findings on recombining genes in these hardier seagrass strains of the Halodule genus at the Benthic Ecology Meeting in Virginia Beach, Va., in early March.
Over a year has passed since McCoy transferred to her current post from the Florida Atlantic University Harbor Branch Oceanographic Institute, where she worked between 2021-24. A joint study conducted between Harbor Branch and the Oceanographic Society observed the “mass die-off” of separate seagrass patches under their watch, she said.
“In the middle of this large experiment,” McCoy said, “there were two sites: one near Fort Pierce and one just near the back of our property.” She added researchers at both facilities “took a lot of time and effort to build” fences protecting these patches from errant herbivores including turtles and manatees.
That did little to protect them from the turgid waters of the lagoon cutting off needed sunlight for the grass, killing them. These samples, however, could be taken back and compared with other data on file from the meadow, which produced seagrasses that have survived for “years,” McCoy said.
“Luckily,” she added, “because we did the out-planting experiments, we used grass that’s in our experimental meadow,” which compared favorably to “the few pieces of grass that survived” the die-off.
“The first thing we needed to do before we could look at those survivors,” McCoy said, “was that we had to sequence the genome. … Now, we basically have the instruction manual for all the genes that are included in Halodule. We can take those that are in our meadow and start growing those up because we know they survived a mass mortality.”
The same mortalities that befell plant life in the lagoon also killed masses of bivalves of the Chione genus, according to joint studies by Harbor Branch and the University of Florida.
Dr. Todd Osborne, a leading researcher at the UF Whitney Lab for Marine Bioscience in St. Augustine, collected a similar range of surviving clams from the lagoon. He and McCoy developed a strain of “superclams” that could weather the same toxins, “but he didn’t understand the genetics behind that,” she said. “We started to collaborate because that’s something I can help with.”
Some of these clams have remained on the Oceanographic Society campus for “years” after their collection and interbreeding, according to McCoy. “Rather than just putting animals and plants out in the environment without knowing anything about their genetics, what we can do is, sort of, learn more about the genetics that are associated with resilience.
“When I think about resilience, I think about physiology and cell behavior,” she added. “One of the things that we know is important is genetic diversity; so, the more individuals that have more genotypes that are out there, the more the population can deal with different stressors.
“That changes a bit when you have one stress that’s very strong,” she said. In one experimental instance, “if you have a high temperature for a very long time, most of the individuals that are not resilient die off; your genetic diversity has decreased and you just have a group of individuals that is really good at surviving that high temperature.”
Thus, the population of an organism begins to “re-diversify” when exposed to other members of the same species, according to McCoy. “If we knew those genes, then we could make a gene array to sample other grasses,” she said. “I could go to other facilities, take samples of their grass, and say, ‘this grass in this region of your nursery is highly resilient.’”
That recombination would extend past life rooted to the seabed. “I think about clams and seagrass a lot but we could be talking about fish, as well,” McCoy said.
These findings, altogether, lend to a rich body of research into the lagoon and coastal waters that extends well past 50 years.
“Like many other places on Earth, humans have changed the (lagoon) and the ocean,” McCoy said. “Our coastal areas are not healthy – it’s true – and I think that a lot of times, people feel like there’s nothing we can do: sort of powerless to make changes. It seems like such a huge problem.
“I feel like that sometimes, too,” she added, “but that’s not helpful; that kind of attitude (is) part of the problem. I just refuse to go down that road and constantly challenge myself with trying to understand how to solve these problems.”