California Sea Grant Aims to Stem the Tide of Invasive
Marine Organisms

September 5, 2006

By: John Stumbos

The battle against invasive marine organisms that harm California’s native plants, fish and wildlife is getting a boost with a renewed effort to educate the maritime industry, government regulators, scientific researchers and the public.

The West Coast Ballast Outreach Project (WCBOP) launched phase two of its effort with a grant from the CALFED Bay-Delta Program by featuring a freshly revamped Web site and newsletter, and a series of upcoming workshops and seminars. The ballast project is a creation of Jodi Cassell, San Francisco Bay region marine advisor for UC Cooperative Extension’s statewide Sea Grant Extension Program (SGEP).

“Aquatic invasive species pose serious economic and environmental threats,” Cassell said. “One way invasive marine organisms are transported from distant locations is in the ballast water of ocean-going ships. For instance, a ship transporting goods across the Pacific may pick up ballast water in different Asian ports of call, and then release this water and associated organisms into the environment at U.S. ports of call—and vice versa.”

mitten crab

Chinese Mitten Crabs (Eriocheir sinensis).
Photo © Carolynn Culver

The San Francisco Bay Area has become a virtual poster child for the problem of invasive aquatic organisms. The floor of the bay is covered with exotic Asian clams (Potamocorbula amurensis) that essentially strip mine tiny organisms called plankton out of the water. Plankton form the base of the food chain and thus changes in their populations will have a ripple effect through the largest estuary on the West Coast.

Other species that have received a fair amount of notoriety include the Chinese mitten crab (Eriocheir sinensis) and European green crab (Carcinus maenas). The mitten crab is of special concern because it can burrow deep into riverbanks and levees and can multiply into enormous populations that could clog critical transfer points in the state water system. The European green crab can out-compete native crabs, such as the commercially valuable Dungeness crab (Cancer magister), for food and habitat.

These aquatic invaders also pose potential threats to humans. One recent study found that 93 percent of foreign ships coming into the East Coast’s Chesapeake Bay carried bacteria that cause human epidemic cholera.

Ballast helps keep ships stable and functioning safely, but that water must be adjusted as ships are loaded and unloaded. Current management strategies to prevent introductions of aquatic invasive species (AIS) via ballast water are limited to open-ocean exchanges. Exchanging ballast water on the open ocean can be tricky. In rough seas it can be dangerous. So the maritime industry is looking at alternatives.

On-board treatment systems using UV irradiation, filtration, ozonation and other emerging technologies are in development. Experimental systems are being tested now on ships like the Moku Pahu, which sails back and forth between the Port of Oakland and Hawaii with shiploads of sugar cane. The Moku Pahu is using a chlorine dioxide generation system to treat ballast water. The chlorine dioxide kills the organisms and then dissipates to undetectable levels within 24 hours.

However, adapting experimental technologies to ship level has been challenging. Large ocean-going ships deal with huge volumes of water. Furthermore, different ship types may have radically different tank orientations and placements. To date, no on-board technology has proven a viable solution for treating ballast water.

Marine stowaways can also be found aboard other nooks and crannies— growing on ship hulls, clinging to anchors and chains, tucked away near intake valves. As reported in the current Ballast Exchange newsletter, “sea chests” provide ideal refuge for a long ocean journey. These built-in recessed areas are where ships’ hulls house intake water pipes for engine cooling, ballast and fire-fighting.

The California Sea Grant Extension Program inaugurated the ballast outreach project in 1999. Its aim is to facilitate communication among industry, regulators and researchers involved in ballast water management on the West Coast. An award-winning poster and thousands of companion brochures were distributed to domestic and international shipping companies, ports and government officials to educate them on the ballast water threat.

With similar goals for the second phase of the project, extensive outreach activities will continue through December 2008. West Coast Ballast Water Outreach Project staff have already revised and updated the brochure and poster and significantly broadened its distribution. The project newsletter, Ballast Exchange, has a new look and will be published twice a year with a wealth of information on ballast water, vessel fouling and marine invasive species.

WCBOP Coordinator Holly Crosson administers the project from UC Davis. The program representative oversees the WCBOP’s database and Web site. Both WCBOP team members give educational presentations on the project’s activities and interact with a 50-member advisory committee.

“We are so fortunate to have a large advisory committee comprised of a broad range of stakeholders who guide our outreach efforts,” Crosson said. “That enables us to focus on issues that matter to our audience.”

“The threat to California’s ecosystems is not going to go away,” Cassell says. “The best thing we can do is to educate people so they can take the preventative measures that will help lower the risk of invasion of aquatic nuisance species through ballast water and other avenues of introduction. In the long run, prevention is significantly cheaper and more effective than trying to control and manage invasive species once they are established.”

Two years after completing his California Sea Grant State Fellowship, Giovannini moved from Maui, where he had been a project manager for a company that raised tropical fish for the aquarium trade, to Tanzania. There, he became the academic director of a 15-credit semester abroad program in wildlife biology and conservation, offered through the Vermont-based School for International Training, which – if the name rings a bell – once trained U.S. Peace Corps volunteers. His course – he designed, taught and staffed it – included taking college students on field trips, aka safaris, through east Africa’s spectacular Serengeti grasslands.

He returned to the United States in 2001, with his African wife and their young son, now 7. “My parents were getting older,” he said, “and my wife wanted to see America, and go to school and improve her English.”