Get on Board for the Climate

Get on Board for the Climate Seaweed and Shellfish: Feast of the Future

Martha Walden, 11th Hour

Three days of the Humboldt Bay Symposium for a Sustainable Blue Economy, September 28-30, painted a picture both sobering and hopeful. This virtual conference brought together thinkers and doers from all over Humboldt County and the state to assess the health of Humboldt Bay and ocean ecosystems. As the climate changes, so does our relationship to the physical systems that have always sustained us. Now we must help the ocean to sustain itself.

Many symposium speakers reported on the ways that our marine world — from estuaries to upland watersheds — has already been impacted and the steps that have been taken to restore the ecology. A healthy marine ecosystem is essential to life on the entire planet. It's stunning to realize that the world's oceans are full of plastic and mercury, acidifying fast, with many of their inhabitants struggling to survive.

The collapse of northern California's kelp forest is an example of particularly dire domino effects. First, the mysterious wasting disease struck sea stars several years ago. Their almost complete disappearance gave sea urchins a free pass to multiply uncontrollably and gorge themselves on kelp. Add some unhealthy warm water events that are also hard on kelp and you have the recipe for environmental disaster.

James Ray from the California Fish and Wildlife Department sounded a cautiously hopeful note about a gradual turn to normal as sea star populations recover, and divers remove thousands of purple urchins and turn them into fertilizer.

The second morning of the symposium sounded out some heady and hopeful ideas for the future. One is regenerative ocean farming. Seaweed, mussels, scallops, clams and oysters are grown on ropes that dangle underwater. This mimics the polycultures that the ocean fosters naturally but in a way that is particularly efficient for harvesters and serves the ecosystem.

Those of you who are not huge seaweed and shellfish fans may want to consider the extremely low carbon footprint of these crops, plus the fact that they need no irrigation or fertilizer. Bivalves clean the water. The seaweed helps to restore the ecosystem by providing habitat and absorbing excess phosphorus and nitrogen. People eat it too. It might be a major food source of the future. Seaweed also makes an excellent fertilizer and can even be stock for bio-plastics.

As many EcoNews readers know, seaweed farming has already begun in Humboldt Bay. The Solutions Summit in August reported on the partnership between Humboldt State University and GreenWave, an environmental nonprofit. The two chiefs of that partnership are Fisheries Biology Associate Professor Rafael Cuevas Uribe of HSU and California Reef Manager Karen Gray. Both of them participated in the symposium.

You can't see the results of this collaboration even though the farm is close to the shore. It's all underwater with just a few buoys to guide the student farmers who are learning not only about growing seaweed but also measuring the remediation effects on the water.

The last day of the symposium was all about sea level rise. Yes, that big ocean is coming for us as ice caps and glaciers melt in our warming world, so we better get ready. We're on the brink of ever bigger changes, but some of those will provide opportunities for a sustainable blue economy.

Those of you who are not huge seaweed and shellfish fans may want to consider the extremely low carbon footprint of these crops, plus the fact that they need no irrigation or fertilizer. Bivalves clean the water. The seaweed helps to restore the ecosystem by providing habitat and absorbing excess phosphorus and nitrogen. People eat it too. It might be a major food source of the future.