Dry dock raises aquatic-invader questions

BATH – Exotic marine organisms attached to the hull of Bath Iron Works’ new dry dock are raising questions about the adequacy of environmental regulations to protect the state’s waters from aquatic invaders.

Betsy Ham, the Kennebec Coalition coordinator for the Natural Resources Council of Maine, said the case begs a question: “Shouldn’t this dock have been inspected before it gets into the Kennebec River?”

Algae and snail eggs were found attached to the hull of the 3.5-acre dry dock after its arrival from China, where it was built.

The organisms apparently latched on in Asia and survived much of the 15,675-mile voyage through typhoons and cold and warm seas. As recently as two weeks ago, a diver found some of the organisms still living on the hull.

Researchers working for the shipbuilder are trying to identify the organisms and find out if they may include any invasive species – those that are able to resettle, reproduce and overwhelm native plants or animals.

Bath Iron Works is voluntarily studying the organisms and has not been accused of breaking any rules. The shipyard has had no official comment.

The discovery highlights a growing risk of new invasions as international trade expands and speeds up, bringing more foreign ships to ports such as Portland. Yet, to the surprise of Ham and some conservationists, there are no state or federal regulations aimed at requiring inspections or defending coastal resources against destructive invaders.

“If there are no rules about this, it’s something we should talk of. … That’s just an accident waiting to happen,” Ham said.

Maine’s coast has already experienced such invasions, including the green crab that plagues the state’s commercial clam industry.

“These kinds of events do plant the seed for what should we do in the future,” said James Carlton, a leading expert on invasive species who is advising the researchers in Bath. “The barn door is by no means too late to close.”

Bath Iron Works did take precautions to avoid bringing invasive species in ballast water tanks, but apparently did not inspect the hull before its arrival.

A diver sent into the river soon after the dry dock arrived in February found living creatures on the sides and bottom of the hull. A second dive about two weeks ago found that most of the organisms had died in the cold water, but some were still alive.

The shipyard is expected to conduct a third dive to see if any of the organisms are still alive.

Carlton, director of the Maritime Studies Program of Williams College and Mystic Seaport, said it’s impossible to predict which organisms will resettle and which will die in their new environment.

A large dry dock towed from Guam to Pearl Harbor several years ago carried foreign mollusks that did survive and spread, he said. “It’s believed several invasions may be linked to that dry dock,” he said.

Invasive species can affect entire coastlines when they reproduce and spread. But some Maine conservationists are particularly concerned because the creatures arrived in the Kennebec, a prominent Maine river that has been the subject of expensive wildlife restoration efforts.

“There’s a lot of different species that call the Kennebec home and some endangered species,” said Mark Latti, spokesman for the Maine Inland Fisheries and Wildlife Department. “It’s a unique ecosystem and affects a lot of people.”