Premier Robert Ghiz says the province will buy six properties in the Barclay Brook area from a number of local farmers for about $250,000.
The province says the land is prone to soil erosion and surface runoff.
The purchase was recommended by a government committee formed to prevent fish kills on the Island.
Ghiz says the land will no longer be used for agricultural purposes and will be managed by the Prince County Chapter of Trout Unlimited.
Thousands of fish have been found dead in the area's rivers several times over the past few years.