Gulf oyster reefs in crisis

Gulf oyster reefs in crisis

The settlement of the Deepwater Horizon oil spill fines — the largest pollution penalty in history — will bring an unprecedented opportunity to spend billions of dollars on restoration projects in the Gulf of Mexico region. But new research has found that the fate remains unknown for hundreds of previous oyster reef restoration projects performed around the United States, an investment of more than $45 million and thousands of hours of labor.

In her dissertation, Harte Research Institute for Gulf of Mexico Studies graduate Dr. Brittany Blomberg queried the National Estuaries Restoration Inventory, a database established with the 2000 Estuary Restoration Act (ERA). The act made the nationwide restoration of degraded marine habitats a priority and required the tracking and dissemination of data related to those projects. 

To learn more about restoration progress, challenges and opportunities, Blomberg reviewed database entries for more than 192 oyster restoration projects entered into the National Estuaries Restoration Inventory and found that despite federal requirements to the contrary, monitoring data for those projects were not available. Without that data, it is impossible for researchers to get a big-picture view of the effectiveness of oyster restoration projects over the last decade and develop better strategies for future projects, Blomberg said.

Oyster reefs, once dominant habitats in estuaries worldwide, have experienced greater losses than any other marine habitat. It’s estimated that 90 percent of oyster reef habitats have been lost, compared to historic abundance, Blomberg said. In the Gulf of Mexico, oyster habitat losses number anywhere from 50 to 80 percent. Because of this loss and the many benefits potential benefits oyster reefs offer, oyster reef restoration has become an increasingly popular coastal project.

Evaluating the effectiveness of restoration becomes especially urgent in light of the $20.8 billion Deepwater Horizon oil spill settlement reached with BP in July 2015. That settlement will send billions to the five Gulf States for restoration projects, with more than $160 million earmarked for oyster restoration projects.

“Oysters accomplish a lot within the environment, and provide important ecosystem services,” Blomberg said. “They’re an important food source and support vital fisheries.”

In addition, as filter feeders, oysters remove excess phytoplankton and nutrients to help clean the water column. That helps prevent harmful algal blooms and a form of water pollution known as eutrophication, which can cause hypoxia (areas of low-to-no oxygen in the water) that can be harmful to marine life. Clearer water also promotes sea grass growth.

Oyster reefs also help prevent coastal erosion by buffering storm surge and wave energy that can eat away marsh, sandy beaches and coastal developments such as homes and roads.

The Estuary Restoration Act was one of the first large restoration-funding acts, Blomberg said. Without a central clearing house of monitoring data, it’s hard to learn how that money was spent. Most data is disseminated through single publications or, if the project was conducted by a state agency or nonprofit, maybe not published at all, providing an incomplete picture of overall restoration progress.

“This is a huge restoration opportunity and its biggest impact will be in the Gulf. But the data and knowledge we can gain through these RESTORE funds and their application in the Gulf can easily transfer to locations around the world,” Blomberg said. “It’s important for the restoration community as a whole to be invested in how these projects are being implemented, how the data is being managed and how that information will ultimately be used.”