Algae and Unintended Consequences

Stephen DeAngelis

July 17, 2008

In January, I wrote a post about research involving algae as a potential source of biofuel [The Potential of Pond Scum]. Biofuels edged their way into the news because of rising oil prices and have remained in the news because of the global food shortage. Critics have argued that extensive use of food crops (like corn, soybeans, and palm oil) as feedstock for biofuel refineries has contributed to the food shortage and rising prices. Proponents of algae a feedstock for biofuel argue that, because it is not a food crop and can be grown where food crops can’t be grown, it is a good alternative to pursue. In a May post [Weeds and Biofuels — a Warning], I focused on environmental concerns about using fast-growing “weeds” as a biofuel feedstock. Environmentalists are concerned that use of such grasses could get out of control and that fast-growing grasses could destroy local ecosystems. Now news out of the South Pacific demonstrates the unintended consequences of trying to produce commercial crops of algae by introducing a new species of algae into areas where algae had never before been a problem [“Corals, Already in Danger, Are Facing New Threat From Farmed Algae,” by Christopher Pala, New York Times, 8 July 2008].

“Off the palm-fringed white beach of this remote Pacific atoll [of Butaritari, Kiribati], the view underwater is downright scary. Corals are being covered and smothered to death by a bushy seaweed that is so tough even algae-grazing fish avoid it. It settles in the reef’s crevices that fish once called home, driving them away. Dead coral stops supporting the ecosystem and, within a couple of decades, it will crumble into rubble, allowing big ocean waves to reach the beach during storms and destroy the flimsy thatched huts of the Micronesians.”

Pala reports that the above scene is very reminiscent of what is happening in Kaneohe Bay on the island of Oahu, Hawaii. The seaweed doing all the damage is called Eucheuma. It was introduced to Butaritari as a source of income for locals who have few other means of producing revenue. Unfortunately, the seaweed is destroying the fishing upon which the locals rely for protein.

“Seafood is virtually the only source of protein in Butaritari, complemented by breadfruit and coconut. This equatorial island of 4,000 people is the latest victim of a 30-year global effort to encourage poor people in the coastal areas of the tropics to grow seaweed that, while not edible, produces carrageenan, an increasingly sought-after binder and fat substitute used in the food industry, notably in ice cream. Today, about 120,000 dry metric tons a year are produced, mostly in the Philippines and Indonesia, where the two main algae originate. Kappaphycus alvarezii is most desirable because of its high carrageenan content; Eucheuma denticulatum is less valuable but easier to cultivate. Both were introduced in the past three decades to 20 countries around the world from Tonga to Zanzibar and the result in most of them has been failure or worse. The alga K. alvarezii invaded the Gulf of Manmar Biosphere Reserve in south India a decade after commercial cultivation began in nearby Panban. ‘No part of the coral reef was visible in most of the invaded sites, where it doomed entire colonies,’ the journal Current Science has reported. In the Pacific, for example, the two algae were introduced to 10 countries and are said to be commercially cultivated in three: Kiribati, the Solomon Islands and Tonga. But in the case of Kiribati, interviews with seaweed officials in Tarawa, the capital of this nation of tiny islands sprinkled over a swath of ocean the size of India, reveal that since the first effort to cultivate algae in 1986, the industry has lost money almost every year and the farmers have shown little enduring enthusiasm for the crop.”

Although these seaweed farms are not intended to support the biofuel sector, the unintended consequences that the introduction of an invasive species of seaweed has had in many of these countries serves as fair warning about the need to move cautiously. Seaweed farming ended two years ago in Butaritari, but the seaweed problem remains. Local citizens have no resources (except manpower), to apply against the problem.

“[Henry Totie, a fisherman and the] Butaritari traditional chief, says the only way to prevent Eucheuma (which locals call seaweeda, since it has no local name) from destroying the entire lagoon is for the seaweed company to offer to buy it. ‘Then the people would go out and get it and it would be gone in a few months,’ he said. ‘If they wait, the problem will just get worse.’ [Kevin Rouatu, a stocky, cheerful former banker who runs the Atoll Seaweed Company in Kiribati,] agrees that some sort of noncommercial purchase plan needs to be set up to save the Butaritari lagoon, perhaps with foreign aid.”

The point here is that good intentions don’t necessarily make good sense. To underscore the point (if it really needs underscoring), the algae problem now facing Hawaii was actually instigated by a college professor trying to conduct “useful” research.

“In Hawaii, three kinds of algae were brought in during the 1970s by a professor of botany at the University of Hawaii, Max Doty, who developed the techniques of cultivation that were exported around the world. One species dominates Oahu’s south and the two others, mostly Eucheuma, have spread to about half of the coral heads of Kaneohe Bay. Celia Smith, the successor to the late Dr. Doty at the university, is now a leader in the effort to save the bay. ‘It’s not easy,’ she said, for the seaweeds grow at a rate of 7 percent a week. The university, state and Nature Conservancy devised Super Suckers, vacuum cleaners on powered catamarans that are sucking up 3,000 pounds of seaweed a day each. ‘At the current rate, we’ll need 10 years to clean up the bay,’ says Brian Hauk, the state aquatic invasive species supervisor.”

Finding a way to use algae as the feedstock for the biofuel industry might help with the development of better harvesting techniques that could be used to clean up some of the trouble spots around the globe. It could also have the unintended consequences of fostering algae farms in inappropriate areas and spread the challenges already faced by sensitive ecosystems. Rarely can a silver bullet solution be found to any challenge. Good research, good planning, and good consequence management are critical for any new venture to succeed in a way that the benefits outweigh the risks.