NMFS approves and implements Framework Adjustment 17 to the Mackerel, Squid, and Butterfish Fishery Management Plan (FMP). This action revises the Atlantic mackerel rebuilding plan, sets final 2026 and projects 2027 specifications, implements additional management measures for the mackerel fishery, and makes administrative revisions and corrections to existing regulations. This action is necessary to respond to updated scientific information from a September 2025 management track stock assessment. The management measures in this action are intended to help prevent overfishing, rebuild the overfished mackerel stock, provide additional opportunity to the fishing industry and achieve optimum yield, and ensure that management measures are based on the best scientific information available.