Oyster plan has big risk, critics say

Adding fertile Asian bivalves to bay said to need more study

October 03, 2004|By Rona Kobell | Rona Kobell,SUN STAFF

The state's plan to help restore the Chesapeake Bay by adding a non-native oyster is moving ahead at a speed that is alarming both the region's scientists and bay officials at several federal agencies.

William P. "Pete" Jensen, the Ehrlich administration's point man on the Asian oyster project, says it is imperative that the state move quickly to replace the native oysters that populated the bay until they were ravaged by disease.

The new oysters could filter away huge loads of pollution, says Jensen, an associate deputy secretary of the state's Department of Natural Resources. And watermen, reeling from the devastation of the native oyster over the past several decades, would have a crop to harvest, he said.

"This is not just an oyster exercise. This is part of the governor's plan to restore the bay," said Jensen, who says the state will go forward with plans next year unless a study now under way raises new concerns.

But fisheries scientists say acting with haste could be reckless. Historically, they say, non-native species often harm the environment - such as the mute swans and rodent-like nutria that have devastated crab habitats along the Eastern Shore.

Introduction of an aquatic species would likely be irreversible. And with only a few months of research conducted, those studying the Asian oyster say it would be impossible to weigh all the risks by Maryland's 2005 deadline.

Those risks include the possibility that the new oyster - a species native to China that can grow as large as a dinner plate - could further spread or introduce disease and beat out the natives for food.

Maryland Natural Resources Secretary C. Ronald Franks, a former state delegate and dentist from the Eastern Shore, is undeterred.

A potential benefit

"Am I willing to introduce another oyster and have it compete? Well, I'm all for competition. I like to play ball," Franks told scientists, state officials and others at a briefing at the Department of Natural Resources last week.

He said Maryland won't proceed if research raises new red flags but that the state doesn't have years to wait for economic and ecological benefits of a return of native oysters. "Am I willing to wait 25 to 100 years for the possibility that it may come back? I don't think that's responsible on my part."

Maryland is spending almost $2 million on research to evaluate the risks and benefits of introducing fertile populations of the Asian oyster, Crassostrea ariakensis. The research includes experiments being conducted this year by scientists from Maryland and Virginia. The two states are working with the U.S. Army Corps of Engineers on the project, but Maryland is footing most of the bill.

Jensen says that the research will be finished by year's end and that the state will make its decision in February.

Scientists are worried by the timetable. "If a decision is made in 2005, it's going to be done against a backdrop of great uncertainty," said Mark Luckenbach, head of a Virginia Institute of Marine Science lab and one of the study's key researchers. "It sounds like the decision is already made."

A report last year by the National Research Council, an arm of the National Academy of Sciences, recommended that the states conduct at least five years of research before releasing the Asian oyster into the bay.

Last month, the director of the federal multi-agency Chesapeake Bay Program sent a letter to Franks requesting a meeting and expressing concerns that Maryland's timetable conflicted with the NRC report.

"While we support an ambitious schedule," the letter said, the "proposed timeline is likely insufficient to reduce the scientific uncertainty associated with the introduction of the non-native oyster to the bay and to make a decision on a project of this magnitude and duration."

Although Maryland officials have not responded to the letter, they have made clear that they see no need to wait five years.

"We respect the opinion that came out of the National Research Council. We don't dispute that opinion. But we have a different opinion based on our own analysis," Jensen said.

Disease concerns

Scientists at the University of Maryland's Horn Point Laboratory are in the early stages of determining whether the Asian oysters are vulnerable to the same predators as the native oyster - a crucial factor in determining whether ariakensis could become an out-of-control nuisance species.

But those experiments are being conducted on juvenile oysters, and researchers say it could take several years to see how they will fare as reproductive adults.

As for disease, initial research suggests that the Asian oyster is resistant to Dermo and MSX, the two parasites that have devastated the natives. But other data suggest that the Asian oyster is vulnerable to the parasite Bonamia. And the possibility that the Asian could bring in disease is very real. Scientists suspect that a Japanese oyster introduced MSX into the bay.

Baltimore Sun Articles
Please note the green-lined linked article text has been applied commercially without any involvement from our newsroom editors, reporters or any other editorial staff.