The Great Lakes Mass Marking Program Act of 2025 aims to improve the management and sustainability of fish populations in the Great Lakes. The main objective is to establish a systematic approach to marking hatchery-produced fish, which will help in understanding and managing fish stocks more effectively. The key provisions of this act include the creation of the Great Lakes Mass Marking Program under the United States Fish and Wildlife Service. This program will involve tagging hatchery-produced fish to track their numbers and effectiveness in the ecosystem.