Many of us likely have spent some time planting seeds in our yards to grow vegetables or flowers. But how do scientists plant seeds to help restore plants in our bays and coastal waters? If you look out on the waters of San Francisco Bay right now, you can see the answer.
Floating on the surface of the bay is a series of “seed buoys.” Each buoy is connected to a mesh bag containing shoots of the underwater plant eelgrass (Zostera marina). These shoots, which are flowering, were harvested by biologists and will soon be releasing ripening seeds. These buoys will move with the tides, distributing seeds that, by next spring, will develop into new eelgrass seedlings on the bay bottom. The seed buoy is a relatively easy, low-tech way of growing this underwater grass. The traditional method of planting eelgrass—by hand in the bay’s floor using scuba divers—can be dangerous, expensive, and labor intensive.
By seeding and transplanting eelgrass in this area where none currently exists, we hope to create vibrant eelgrass beds that provide cover and food for fish, juvenile Dungeness crabs, and birds. Eelgrass beds provide important habitat in California’s San Francisco Bay, serving as nurseries for young fish and foraging areas for many species of fish, invertebrates, and birds. They also improve water quality by reducing turbidity, or cloudiness, of the water.
This work is part of a restoration project which has the ultimate goal of compensating for past oil spill impacts in San Francisco Bay as a result of the 2007 M/V Cosco Busan oil spill. It aims to create 70 new acres of eelgrass habitat at several sites throughout San Francisco Bay over nine years. This project is funded by the legal settlement resulting from the cargo ship Cosco Busan striking one of the towers of the San Francisco-Oakland Bay Bridge and releasing 53,000 gallons of heavy oil into the surrounding waters.
A result of the work of the Cosco Busan Oil Spill Trustee Council, the eelgrass restoration project also is carried out in cooperation with San Francisco State University and Merkel and Associates, Inc.
For more information, you can read about:
- How seed buoys work and why NOAA is using them to bring back eelgrass in San Francisco Bay.
- The Cosco Busan oil spill, resulting legal settlement, and restoration efforts.
- Responding to the Cosco Busan oil spill and the $44 million awarded for restoration.
- A collaborative, regional planning effort to understand, protect, and restore submerged habitats in San Francisco Bay.