\u201cThis is the primary question that we get: \u2018Should we now be removing mangroves from oyster reefs, including restored oyster reefs?\u2019 \u201d she says. \u201cIt is important to share that the mangroves have done nothing wrong – they are simply being mangroves, trees that have hundreds of propagules that disperse in the water via currents.\u201d<\/p>\n
\u201cIt is important to share that the mangroves have done nothing wrong – they are simply being mangroves, trees that have hundreds of propagules that disperse in the water via currents.\u201d \u2014 Pegasus Professor Linda Walters<\/p><\/blockquote>\n
So, what\u2019s at stake if oyster reefs decline to critical numbers?<\/p>\n
\u201cPrimarily, we\u2019d lose water filtration capacity as well as some protection against storm surges and erosion,\u201d Walters says. \u201cEach oyster filters approximately 20 gallons of water per day. Oysters remove sediments and plankton to improve water clarity for species like seagrasses to get sufficient sunlight, and a decline in oyster reefs would cause food loss for birds, crabs and fish. Because oyster reefs also reduce the impact of waves on shorelines, a decline in reefs also may lead to coastal communities experiencing higher storm surges and more erosion.\u201d<\/p>\n
Ensuring that oyster reefs can safely navigate these changes and thrive along with mangroves is a crucial part of coastal restoration efforts, she says.<\/p>\n
\u201cWe work on public lands, state and national parks, so our mission is to provide the science to the park resource managers to help them make decisions,\u201d Walters says. \u201cWhile both species benefit estuaries in numerous ways, tipping the balance so that mangroves dominate and have the potential to completely overtake oyster reefs is a very new concern.\u201d<\/p>\n
For the experiment, the research team did not use live oysters. They instead placed cleaned and emptied shells in mesh bags throughout areas with varying mangrove densities within Mosquito Lagoon and Indian River Lagoon to study the effects of acidification on the shells.<\/p>\n
The results inspired researchers to explore ways to help mangroves and oysters coexist more effectively and continue protecting coastal ecosystems.<\/p>\n
While comparing sediment pH, researchers found a dramatic difference in acidity between habitats. When comparing an oyster reef without mangroves to an oyster reef with mangroves, they observed an 85% increase in acidity while comparing an oyster reef without mangroves to a fully mangrove dominated area, there was 142% increase in acidity.<\/p>\n
Live oysters may be able to protect against acidification and build their shell over time, but that may be a misappropriation of the animal\u2019s limited energy, Harris says.<\/p>\n
\u201cLive oysters probably are going to be able to have some pushback against acidification,\u201d she says. \u201cHowever, it probably would negatively impact their health, because they’re no longer focusing on getting bigger.\u201d<\/p>\n
Harris suggests that future efforts might consider the balance between mangrove benefits and oyster reef viability, potentially altering restoration strategies to mitigate these impacts.<\/p>\n
\u201cIt’s really important to understand that both of these habitat types are essential,\u201d she says.<\/p>\n
![\"shell](\"https:\/\/www.ucf.edu\/wp-content\/blogs.dir\/20\/files\/2025\/07\/shell-dissolution-on-intact-shell-web.jpg\")