The cordgrasses are dying.

Cordgrasses exist as the bottom of the marine ecosystem. If they start to deteriorate, they will take the Gulf ecosystem and the Southern fishing economy down with them.

While the use of Corexit as a dispersant largely contributed to the Cordgrass Effect, certain phototoxins that formed within 6 hours of the spill are mostly to blame. Read more about how these phototoxins were identified here:

IHSJS - Aug 2015 Magazine (page 15)

My next research study dealt with “good” bacteria and fungi that exist within the cordgrasses and help them to sustain themselves. This study showed that the bacteria stopped growing within 24–36 hours of exposure to the toxins previously identified.

SO it's very important to  control oil spill .