Want a side of algae with that? Hawaiian farmers sell seaweed by the seashore

Although a yearning to surf was what first drove native Tucsonan Edward Glenn to Hawaii, what keeps him going back is his life-long interest in marine agronomy. Now, instead of hanging out in the waves, Glenn spends his time on the leeward side of the island of Molokai, working with the local community on sustainable aquaculture projects for the ancient fishponds that dot the island’s south coast.

Rather than growing fish, Glenn, Stephen Nelson and their colleagues are focusing on the edible red seaweed, Gracilaria parvispora. The alga, known as “long ogo” by the Japanese, is eaten by people in Hawaii, Asia and the Pacific and is also a source of agar, a common thickening agent in Japanese cooking. This month the team received a grant to develop new markets for Hawaii long ogo products.

Long ogo was once the most important edible seaweed on Hawaii’s reefs. In the past, people would go out to the reef and yank the seaweed off the rocks or even take the whole rock, Glenn says. Ultimately, the reef populations of seaweed declined. People started to grow another species of seaweed in tanks on land, but the replacement just wasn’t as good.

“This particular seaweed is the one that people desire the most, and it has become overharvested on the reefs of Hawaii,” says Glenn, a professor of soil, water and environmental science in the University of Arizona’s College of Agriculture and Life Sciences (CALS). “Our scientific challenge was to find a way to put the seaweed into a practical aquaculture system. People have been trying for years to grow this particular species, and they haven’t been able to do it.”

However, Glenn and his colleagues have done it. The group, which includes researchers from the department of soil, water and environmental science’s Environmental Research Laboratory (ERL) and others in Hawaii, has developed a way to grow the complete life cycle of long ogo without needing to harvest starter plants from the ocean. Glenn says the sustainable system for growing fresh long ogo is unique in the United States.

Molokai is a relatively undeveloped island, without the coastline-oriented tourist industry prevalent on Hawaiian islands such as Oahu and Hawaii. Many Molokai residents cherish their rural lifestyle and want to continue traditional Hawaiian ways of life, rather than converting the island’s economy to one dependent on tourism, Glenn says. However, Molokai also has limited opportunities for employment. An aquaculture project that focuses on growing long ogo in the ancient fishponds would satisfy a lot of different needs.

A key part of the project is the hatchery, run by Ke Kua’aina Hanauna Hou (KKHH), a nonprofit organization that develops aquaculture enterprises for coastal residents. In KKHH’s hatchery tanks, algal spores are allowed to settle onto rocks or coral chips and start growing. Then those rocks or chunks of coral are given away to the farmers so they can start their own plot of long ogo. Farmers can have a load of seaweed-covered rocks delivered by pickup.

Glenn says the farmer’s next step would be “put ’em out and start a little patch of it and that would be your little patch to harvest and tend.” The starter plants can be grown in a variety of places: an ancient fishpond in the ocean, a land-locked fishpond or even in the effluent runoff ditch from a shrimp-farming operation. The little plots of long ogo that are grown in the ocean release spores periodically, thereby replenishing the natural population.

“This is actually repopulating the reef,” says Nelson, a senior research scientist at ERL whose primary research focus is the Molokai project.

Long ogo is eaten fresh and often combined with other foods. Glenn says, “It’s crunchy and slightly salty, like a pickle without the vinegar taste.” One of his favorite long ogo dishes is ahi poke, a Hawaiian dish like sushi that combines cubes of fresh, raw tuna, pine nuts, chopped ogo and sesame oil with some soy sauce.

Now the long ogo project is a $300,000 enterprise that provides additional income for about 40 long ogo farmers. The project has been so successful that Glenn and his colleagues are looking for new markets for long ogo. The team’s $49,000 grant from the U.S. Department of Agriculture’s Cooperative State Research, Education and Extension Service will let Glenn, Nelson and KKHH develop additional Hawaiian ogo products, such as sports gels, gourmet recipes and healthcare products.

Some large-scale seaweed-processing plants use harsh chemicals to extract the agar, but Nelson sees an opportunity to extract Molokai agar in gentler ways so it can be marketed as an organic product. “We can say this was grown in the pristine waters of Hawaii.”