R.I. Gen. Laws § 20-2-40: Trout conservation stamp required.

No person fifteen (15) years of age or older shall take any trout without first obtaining a regular fishing license and a Rhode Island trout conservation stamp for the current year. Each stamp shall be validated by signature of the licensee written in ink across the face of the stamp, shall not be transferable, and shall be in his or her possession while engaged in the activity permitted under the terms of the license and stamp. The stamp year shall run from March 1 to the last day in February. The trout conservation stamp shall be available at all outlets currently used for the issuance of the fishing license.