A new policy adopted by the Bay Program may help resolve the sometimes sharp differences between jurisdictions over the use and introduction of non-native species in the watershed.

States have the authority to decide what species they will allow to be used within their waterways, but because rivers - and the Bay - cross boundaries, the decision of one jurisdiction can affect another.

The new "Chesapeake Bay Policy for the Introduction of Non-Indigenous Species" is aimed at making sure all the issues related to a species introduction are thoroughly reviewed before a final decision about the introduction of an "exotic" species is made.

"You want to make sure that people make a decision with the best information in hand," said Ron Klauda, director of the Maryland Department of Natural Resources' Chesapeake Bay Research and Monitoring Division, who helped write the policy. "And hopefully , more times than not, they will make the right decision."

Concern about the impact that exotic species can have on an ecosystem was heightened by the accidental introduction of the zebra mussel in the Great Lakes in the mid-1980s, which has threatened the survival of native species and forced industries and municipalities to spend tens of millions of dollars in control efforts.

In the Bay watershed, officials debated for more than two years about whether an experiment using Japanese oysters should be allowed in the Bay [see related stories], and disagreements have erupted over the use of the non-native grass carp to control aquatic plants in ponds and impoundments within the Chesapeake watershed.

With increased desire to research non-native species, and a growing interest in aquaculture, the new policy establishes a mechanism for all affected jurisdictions to discuss the issue.

Under the policy, when a state plans to allow an intentional first-time introduction - or a significant change in its existing requirements for non-native species - an ad-hoc panel is created to review the matter. The panel contains representatives from each jurisdiction who have technical backgrounds on the issue, and at least two other scientists or technicians with expertise on the species in question.

"With these kinds of panels we will eliminate a lot of the problems we have experienced before with concerns over Japanese oysters, the grass carp, and other critters," said Dan Terlizzi, of Maryland Sea Grant, who chairs the Bay Program's Exotic Species Workgroup. "It doesn't mean that we will not introduce exotics into the region - it's inevitable that introductions, intentional and unintentional, will occur - but the policy ensures they will be well thought out and carefully discussed."

The panel is to complete a review within 45 to 60 days, and may make recommendations about how a particular jurisdiction should proceed with its plan, including possible changes in its permit requirements. The panel's recommendations are only advisory.

The policy applies to first time introductions of non-native species into any water body that could potentially flow into the Chesapeake Bay. The policy does not apply to species already used in open waters, such as rainbow trout, or to confined waterbo dies which use water recirculation units.

Since the policy was adopted in December, one ad-hoc panel has been created. The Virginia Department of Game and Inland Fisheries requested that a panel review a request by Virginia Power to introduce 6,300 grass carp into the three cooling ponds of a po wer plant at Lake Anna on the North Anna River, a tributary of the York River. The utility wanted to use the fish to control the growth of underwater grasses in the ponds.

Though Virginia already allows the use of sterilized grass carp in ponds through a state permit, DGIF considered Virginia Power's request a "change of scope" because it involved so many fish.

The ad hoc panel met this spring and concluded the project could go ahead with safeguards planned by DGIF - which included such things as tagging each fish so they could be identified if they escaped from the impoundments - and recommended additional mea sures as well.

For example, the ad hoc panel recommended - and DGIF agreed - that a U.S. Fish and Wildlife Service representative be present at the Arkansas hatchery to assure that each fish sent to Lake Anna is, in fact, a triploid. Triploids are specially treated to have three sets of genes instead of two, which lowers the potential for reproduction. The panel also made technical recommendations about screening the fish used in the project, and for sampling downstream waterways for any escaped fish.

Participants said the panel worked well.

"It was a good test case," said Gary Martel, DGIF chief of fisheries. "It allows an open forum so we're not in a situation where one states simply does what it wants because, 'it's my waters.' It's a shared resource."

And although Maryland has long opposed the use of grass carp in Virginia and Pennsylvania, fearing the escaped fish could consume ecologically important grasses in the Bay, its representative on the panel voted to allow the Lake Anna use because adequate safeguards were included.

The policy also provides a framework for jurisdictions to work together on other issues relating to exotic species. In coming months, they will exchange information about what species are routinely allowed into their waterways, and develop a list of path ogens which could be inadvertently brought into the Bay basin with a particular species so adequate screening methods can be used.

In addition, the policy outlines actions to help prevent accidental introduction of non-native species such as the zebra mussel, which has caused havoc in the Great Lakes. The policy calls for cooperative monitoring efforts, public education activities, and to support a national policy dealing with "ballast water" which is discharged by freighters from all over the world into ports around the Bay. Zebra mussels are thought to have been transported into the Great Lakes via ballast water.

The policy also calls for holding special symposiums called "critical issue forums" to bring together experts and managers to discuss emerging issues. One such forum is already being planned to discuss techniques used to render non-native species sterile.

"The fact that we have this exotic species policy has raised the consciousness of everybody about exotic species to the point where it would be difficult to just run out and introduce something without telling anybody," Klauda said. "I feel more comfortable now with the issue."