The Morro Bay ecosystem is in peril because eelgrass critical to the California central coast estuary's health is disappearing.
About 80 percent of the bay's estuary's eelgrass disappeared and scientists are calling it a crisis.
Ellgrass offers spawning areas for fish and food for migrating birds.
Eelgrass covered 500 acres of the intertidal flats and bay shallows in the 1970s. There are less than 100 acres now.
Divers gathered during the weekend and transplanted about
8,000 eelgrass plants from an area near the mouth of the bay to back bay areas where losses have been greatest.
The San Luis Obispo County Tribune says sedimentation and algae blooms could be hampering photosynthesis. Eelgrass beds may also have been scoured during Fukushima tsunami tidal surges in March 2011.