04/13/2007 07:58:12 AM PDT

In an attempt to further preserve two endangered wetland plants, the U.S. Fish and Wildlife Service has designated 2,621 acres of marshland in Solano, Contra Costa and Napa counties as critical habitat.

The final ruling, published Thursday under the Endangered Species Act, will protect the Suisun Thistle and the soft bird's-beak. The two plants are found only in the tidal wetlands of the Suisun and San Pablo bays.

Critical habitat is an area containing features essential for the conservation of a threatened or endangered species that may require special management considerations or protection.

Most of the designated land, 2,215 acres, sits in Solano County, with 384 acres in Napa County and 22 acres in Contra Costa County. The designation includes 2,052 acres of critical habitat in Solano County for the Suisun thistle and 2,276 acres for the soft bird's-beak in Contra Costa, Napa, and Solano Counties.

Among the critical habitat for the two endangered species, there is an overlap regarding the number of acres designated. That overlap, approximately 1,706 acres, is in Solano County in the Hill Slough and Rush Ranch units in the northern portion of the Suisun Marsh

Most of the wetlands are owned by the state, public agencies and the Solano Land Trust. Only 309 acres are privately owned. Because this land is already protected there will be little change, according to Al Donner, assistant field supervisor for the U.S. Fish and Wildlife Service.

Donner said the designation won't greatly affect how the area is managed, but rather bring attention to the plants and the areas.

"It's like raising a billboard about the plant," he said. "It just makes people a little more aware of the tidal marshes."

Critical habitat is an area containing features essential for the conservation of a threatened or endangered species that may require special management considerations or protection.

Ben Wallace, conservation project manager with the Solano Land Trust, said the area already protects the two plants and would take any appropriate steps to do so further if prompted to by the fish and wildlife service.

"We've always been careful with the use of the marsh," Wallace said. "We try and work proactively. If we have any questions, we would call them."

One of the main adversaries of the plants are the feral pigs that inhabit the area. He said licensed hunters are brought in to combat the problem, but they continue to be a nuisance.

"There's only so much we can do. Pigs go where they want," Wallace said.

Danny Bernardini can be reached at county@thereporter.com.