ALBUQUERQUE, N.M. (AP) — Methane emissions from oil and natural gas production in New Mexico are higher than what state and federal regulators have measured and the failure to capture the pollution is costing the state revenues and royalties, environmentalists said Thursday.

Representatives with the nonprofit Environmental Defense Fund released a report that aims to quantify the amount of methane intentionally released through venting or flaring processes as well as gas lost through unintentional leaks.

New Mexico's producers are emitting 570,000 tons of methane annually, amounting to more tha...