Dec. 29 (UPI) -- The Caribbean's coral is environmentally stressed, according to the conclusions of a recently-completed 25-year survey.
For more than two decades, researchers observed environmental changes and ecological health indicators as part of the Caribbean Coastal Marine Productivity Program. They published the results of the program -- the largest, longest of its kind -- earlier this month.
Though scientists didn't measure significant increases in water temperature across the region, they did find decreases in water quality at 42 percent of the surveyed sites.
"We're seeing important changes in local conditions, like decreases in visibility associated with declining water quality and the increasing presence of people, but we're not picking up global-scale changes, like climate warming," Iliana Chollett, post-doctoral fellow at the Smithsonian Marine Conservation Program in Fort Pierce, Fla., said in a news release.
Most ocean temperature monitoring efforts look at surface temperature. During the 25-year survey, scientists measured underwater temps.
"Satellites only measure temperature at the surface," Chollett said. "Underwater temperatures are much more variable, and it may take decades of data to reveal a significant change, so we're not sure if this means that we just don't have enough data to detect it yet."
In addition to collecting temperature readings, researchers also regularly measured salinity and visibility at 29 test sites among mangroves, seagrass beds and coral reefs. Researchers chose sites that were relatively secluded, free from direct interference from cities and human populations.
The survey included coastal sites in Barbados, Belize, Bermuda, Bonaire, Colombia, Costa Rica, Florida, Jamaica, Mexico, Panama, Puerto Rico, Saba and Venezuela.
Though the survey results reveal worrying trends, researchers suggest the ecological changes they discovered can be mitigated and reversed.
"One positive implication of this report is people are capable of dealing with local change by regulating pollution and runoff," said Rachel Collin, director of the Bocas del Toro Research Station at the Smithsonian Tropical Research Institute. "If people get their act together very soon, there is still hope of reversing some of these changes."