Puerto Rico Karst Conservation Act of 2003 - Authorizes the Secretary of Agriculture to acquire land in or immediately adjacent to the Karst Region of Puerto Rico for the purpose of protecting and managing the tropical forest areas of the Region, with particular emphasis on water quality and protection of the aquifers.
Authorizes the Secretary to use funds from the Puerto Rico Karst Conservation Fund (established by this Act) as well as funds under the Forest and Rangeland Renewable Resources Research Act of 1978, the Forest Legacy Program, and the Land and Water Conservation Fund.
Requires these lands to be managed in accordance with the Forest and Rangeland Renewable Resources Research Act of 1978.
Makes all lands in such region eligible for inclusion in the Forest Legacy Program.