A rare chunk of Sussex County known as Armstrong Bog, where the wildlife includes the threatened bog turtle, is the subject of a $500,000 federal preservation grant announced today.

The grant issued by the U.S. Fish and Wildlife Service is part of $57.8 million being distributed in 27 states to support land acquisition and conservation planning for endangered species, Department of Interior Secretary Ken Salazar announced today.

Armstrong Bog, in Frankford Township next to the Wallkill River National Wildlife Refuge, is a 324-acre calcareous fen -- a rare type of groundwater-fed wetland filled with tussocks, grass and sedge-type vegetation.

Found there along with the bog turtle, which is on New Jersey's endangered species list, is the state-protected wood turtle and a rare plant known as Fraser's Saint-John's-wort.

Many groups, including Frankford Township, the New Jersey Trust for Public Land and the Friends of the Wallkill River National Wildlife Refuge, have been trying to preserve Armstrong Bog for years. The $500,000 is only part of the amount they say is needed to buy the privately owned parcel, which could cost more than $2 million to preserve.

The New Jersey Natural Lands Trust, with the help of the Trust for Public Land, had submitted a grant application for the funding through the federal Cooperative Endangered Species Conservation Fund.

"It's great news," Anthony Cucchi, director of the public-land trust, said of the announcement. "But this is a very complicated project, and it's likely the entire parcel will have to be preserved through phases. Thankfully we have a landowner willing to work with us."

Although portions of the parcel are still farmed, preservationists contend it all should be protected.

"Armstrong Bog is a prime piece of rare habitat we've been working to preserve because it's important to species like the bog turtle," said Marie Springer of the Friends of the Wallkill group.

Other efforts are under way to add large tracts in the same region to the federal Wallkill Refuge, and while the state is leading the Armstrong Bog preservation effort, partnerships between state and federal agencies, as well as with private groups, are common in protection campaigns.

"The U.S. Fish and Wildlife Service will be pleased and happy to work with the state and other involved partners once the land is acquired to work together to manage the land," said Edward Henry, refuge manager. "These kinds of grants generally preclude federal ownership of the land, so our role will develop through a partnership of some kind.

"Partnerships are the key to success at Wallkill River National Wildlife Refuge, and Armstrong Bog is a prime example of this."