Years of fishing trips to Croil Island taught Jerry E. Laramay the secrets of the undeveloped state park on the St. Lawrence River.

With a gust of wind or glimmer of sun, the guide for American Carp Adventures can tell you where carp or bass are likely to be caught off the shores of the 500-acre island.He spent the last week taking a group of nine English fishermen to the island almost daily.

On Monday, when St. Regis Mohawk chiefs and Gov. George E. Pataki in Albany signed an agreement that may settle a 21-year-old, 15,000-acre land claim and grant the tribe ownership of the island, the fishermen boated out to the property, caught a couple of whoppers and retired to Mr. Laramay's Route 131 Lakeview Motel.

"I use that exclusively for my business. This is very disturbing news," the 17-year-veteran fishing guide said.

Since the state is offering to give to St. Regis Mohawks Croil and neighboring 600-acre Long Sault islands as part of a $100 million settlement, Mr. Laramay and other sportsmen hope they will not lose the opportunity to use for recreation the property now owned by the New York Power Authority.

"I'm very worried about our fishing business. You fish off the shore, and most of our prime spots are off the island," Mr. Laramay said.

The slightly hilly Croil Island is a quiet hot spot among north country residents, although tribe attorney Brad Waterman said he was unaware that the island is used for business purposes.

Croil Island's large hardwood- covered land, surrounded by thick underbrush, offers people excellent deer and duck hunting opportunities, and its beaches are prime for fishing, picnics and camping.

"I'll miss it very much. It's among the better places," said Massena hunter Paul C. Lambert, who takes his boat out to Croil Island about six times each year.

The tribe has not determined what it will do with the islands if the terms of the agreement, which require Mohawks' approval in a referendum, are enacted, tribe spokeswoman Jennifer Jock said.

"The tribe is committed to being good neighbors, but understand - the islands are going to become reservation land," Mr. Waterman said.

Mohawks cannot build casinos, resorts or industrial structures on the islands, according to the agreement.

The tribe must save the land for recreational purposes or any ceremonial activities, NYPA spokesman Peter A. Barden said.

The memorandum of understanding the chiefs signed with the governor also outlines gaming rules for the Hogansburg Akwesasne Mohawk Casino and the planned $500 million Catskills Mohawk Mountain Casino.

The tribe, in the settlement, will drop its claim for the home of NYPA's St. Lawrence-FDR Power Project, Barnhart Island. NYPA will pay Mohawks $70 million over 35 years and the tribe will support the 50-year relicensing application for the power dam.

Mr. Waterman said the tribe may want to meet with non-Indians who use the island. Mr. Barden said he did not know how the agreement will affect non-Indians' public access to the property.

"We're not even thinking that far yet. For now they can keep on doing what they're doing. We just have to take it day by day," Mrs. Jock said.