Guest Post | Eelgrass restoration

Eelgrass restoration
Crystal is researching eelgrass restoration in the San Francisco Bay.

Crystal Weaver is a master’s student in the Boyer Lab at the Romberg Tiburon Center for Environmental Studies at SFSU. She has contributed to research in several coastal ecosystems throughout California, including sandy beaches, tidal marshes, and vernal pools. With a passion for puzzles of all kinds, she is driven to solve pressing ecological questions with an interdisciplinary approach.

Half of the fun of getting to do coastal restoration work is exploring the puzzle of it all. Where will it work? How can we make it more efficient? Or, more challenging yet… where did we go wrong?

As a graduate student at the Romberg Tiburon Center for Environmental Studies at San Francisco State University, I work at the mercy of the tides to restore eelgrass in the Bay. Eelgrass is an underwater plant that creates a rich ecosystem of marine life, including commercially important species of fish and crabs. It grows naturally in the Bay, but it covers a relatively small percentage of the submerged land that it could potentially inhabit. Thus, my colleagues and I, led by Dr. Katharyn Boyer, tromp out through the mudflat to plant eelgrass at sites throughout the Bay where it could possibly thrive, creating critical habitat for a wide range of marine species.

The thing is, sometimes our transplants survive, but sometimes they don’t. We can explain some of these casualties fairly easily. Maybe we had a heat wave, and the water temperature got too hot. Maybe the wind kicked up for weeks, stirring up sediment in a cloud that blocked the light from getting to the plants. But there are still some things we don’t understand yet, like what’s actually happening in the sediments when we transplant the eelgrass.

My thesis work digs into eelgrass bed sediments – literally – to look specifically at the microbial communities that reside where the healthy eelgrass grows. Because microbes are what break down decaying material and turn it into usable nutrients for the plant, they play a pretty large role in how well a plant functions. We think there may even be groups of specific species of microbes that help transplanted eelgrass survive, sort of like plant-probiotics.

Sampling from natural eelgrass beds, restored beds, and failed restoration sites, we’re piecing together which species of microbes may play a role in “helping” the eelgrass survive. Ultimately, we could culture these microbes and plant them directly with the eelgrass. It’s a tricky and fairly expensive process, using genetic sequencing to sort through thousands of species at a time, but the potential to use this research to improve restoration success is just too exciting to pass up.

To learn more about this research, please visit