Reforesting Mangrove Trees Could Prove Key to Storm Defense in Puerto Rico

Mar 20, 2023
4:55 PM

Mangroves sit in the Jobos Bay National Estuarine Research Reserve in Salinas, Puerto Rico, Tuesday, May 3, 2022. Last year, Puerto Rico’s Justice Department has launched a criminal investigation into destruction in the ecological reserve that protects one of the island’s most extensive mangrove forests.(AP Photo/Carlos Giusti)

SAN JUAN — The sun shone brightly on a recent Saturday morning in Puerto Rico as a group of three dozen people grabbed mangrove roots from a bucket provided by organizers. Some of the planters were clad in waders while others wore flip-flops and board shorts, but all came to the beach town of Isabela for the same purpose: to restore the mangrove forests to their former glory in hopes of preventing the beach from moving inland.

“The quicker we seed, the faster the forest will grow,” Andreina Alexatos, green infrastructure coordinator for the San Juan Bay Estuary Program, told Latino Rebels, adding about 95 percent of the mangrove forest has been destroyed.

Over the course of two hours, Alexatos’ group, mostly made of university students, members of the grassroots environmental organization SurfriderPR, and volunteers, planted over 400 saplings. Only about 10 percent will survive by Alexatos’ estimate, but that could be a game-changer for the heavily destroyed mangrove forest.

Without such help, the forest would likely take between 30 and 50 years to start looking like it once did. Thanks to the saplings being planted, that timeframe could be shortened to as much as 10 years, Alexatos says.

Part of the reason for the reforesting campaign in Isabela and other places along Puerto Rico’s northwest coast is the alarming rate at which the island’s mangrove forests are disappearing, the effects of which are already being felt. During the last few decades, concrete has begun covering more and more of Puerto Rico’s beautiful beaches, leading to the destruction of mangrove forests that once protected the coastline from rising sea levels.

Coastal Protectors

Puerto Rico has always been particularly susceptible to strong storms due to its location, on the boundary between the Caribbean Sea and the Atlantic Ocean. But the worsening effects of climate change, such as an increase in storm strength and ocean acidification, have caused the islands to experience stronger-than-average storms since the beginning of the century.

The destruction left the wakes of hurricanes María and Fiona remain strong in the minds of millions of Puerto Ricans. After Fiona, which brought intense flooding to some areas, many houses along the western coast flooded because the mangrove forests, which act as natural barriers between the waves and the land, had been destroyed.

The destruction of mangrove forests, whether intentional or unintentional, and its effects are an issue of climate justice for Puerto Ricans because it not only exposes the population to disasters, but has also left Puerto Rico with a disappearing coastline, flora, and fauna.

On the recent Saturday in Isabela, as dozens of people spread over a massive pool of water where the once lush mangroves had turned into brittle and gray branches, the eeriness of being among dead trees while surrounded by green was unavoidable.

“In (ecological) systems like Puerto Rico, where there used to be a ring of mangroves around the island that no longer exists, those areas are involved in systems of erosion, which is why we’re seeing the loss of beaches. But when you lose beaches, you lose territory, and a little bit here and there eventually adds up to a lot,” said Rafael Jusino, a professor of marine biology at the University of Puerto Rico.

Since mangroves prevent coastal erosion, they give the coastline its shape. If they are destroyed, the ocean travels inland, making it incredibly difficult or even impossible for them to regrow where they once stood.

As rising sea levels affect coastlines, mangroves are expected to move inland and encroach on dry forest, affecting the other plants and the animals that depend on such habitat. After Hurricane María, red mangrove fringes and basins that were subject to tidal flooding suffered a 22 percent noticeable mangrove mortality rate only 11 months after the storm.

“(Reforestation) efforts are really not just to keep the plants but to keep the land there,” said Elsie Rivera Ocasio, a biology professor at the University of Puerto Rico.

Mangroves also function as powerful carbon sinks, sucking up carbon dioxide from the air and storing it in their roots and the surrounding sediment. While they only cover about 0.1 percent of the Earth’s surface, mangroves store “up to 10 times more carbon per hectare than terrestrial forests.” They also retain toxic metals in their roots that could be harmful if allowed to spread through the atmosphere.

Authorities in Debt

Unscrupulous developers have decimated mangrove forests along the coast, which is why projects like Prof. Jusino’s with the Environmental Protection Agency are incredibly important in preventing buildings built too close to the beach from falling into the ocean, he explains. Such building projects have become evermore present along the Puerto Rican coast over the past decades because governmental agencies like the Puerto Rico Department of Natural and Environmental Resources have not enforced environmental protection laws.

“When what you have is just an artificial structure, that dynamic response (to rising oceans) is not present. If the ocean took away the terrain, it’s gone and it’s not going to come back,” Rivera Ocasio, the biology professor, said.

While mangrove restoration is in its infancy in Puerto Rico, efforts to restore destroyed mangroves using site-specific approaches instead of a one-size-fits-all solution have been ongoing for many years in countries like Kenya, Senegal, and Indonesia. However, a survey of 14 locations in 11 countries revealed that large investments in planting “did not result in significant long-term increase in mangrove area or tree survival.”

Clearly, mangrove restoration is tricky business, and experts say it necessitates community participation, long-term monitoring efforts, and early detection systems, which are not generally implemented in any country. Studies have found that conservation has been significantly more effective than rehabilitation and emphasize passing laws to protect mangroves instead of restoring them after the fact.

“The most important thing is not losing even one single tree right now that we can conserve, because it’s already there and it’s adapted,” Rivera Ocasio said.

When the Balneario de Jobos was built along the coast and later bought by the municipality of Isabela, part of the drainage that allowed rainwater to exit caused the salinity of the water to plummet and led to a mass of dead and dying mangroves. Similar events have occurred throughout the archipelago, and half a dozen illegal constructions have been denounced by environmentalists in 2023 alone.

“They are going to lose their property eventually because they have no defenses anymore,” Jusino explained.

For Puerto Ricans, the interconnection between the destruction of mangroves, hurricanes, and urban expansion illuminates a trifecta of how the archipelago has been decimated by climate change. Many complain that mitigation strategies have not only been undermined but actively avoided by the government agencies charged with enforcing them, in favor of selling off plots of land so developers can build luxury developments unattainable to most Puerto Ricans.

These luxury projects then suffer greatly from the lack of climate change mitigation or adaptation measures, only to get slapped by even worse climate change effects later on. This vicious cycle repeats until entire areas are deforested, overdeveloped, and eventually abandoned.

Allies for Climate Resilience

For many in Puerto Rico, beaches are the only place where they can live rent-free in a society that is only getting more expensive, so their disappearance is a massive hit to regular Puerto Ricans.

Environmentalists, ecologists, and biologists have been sounding the alarm bell for years, but the work of protecting the environment and giving citizens a semblance of climate justice has fallen squarely on their own shoulders while government agencies remain seemingly asleep at the wheel.

Yet, while many activists, organizers and earth scientists see the negatives in what they are forced to do, they also realize how their work has allowed them to build a community committed to protecting the environment and teaching the importance of environmental protection before it is too late to be saved.

This story was published with the support of Climate Tracker’s Caribbean Climate Justice Journalism Fellowship.


Carlos Edill Berríos Polanco is the Caribbean correspondent for Latino Rebels, based in San Juan, Puerto Rico. Twitter: @Vaquero2XL