An apparatus and method are provided for reducing methane emissions from ruminant animals by combusting methane gas extracted from the rumen. The system comprises a conduit configured to transport methane from the animal's rumen to a combustion module mounted externally or implanted partially or fully in a subdorsal position. The combustion module includes a pressure-activated valve, air intake, ignition system, and combustion chamber enclosed by a heat-absorbing roof structure. A control unit monitors internal gas pressure and triggers a spark ignition circuit when combustion conditions are satisfied. An upward-facing camera inhibits ignition if flammable obstructions are detected above the module. A water-filled thermal buffer integrated into the chamber roof moderates exhaust temperature, reducing wildfire risk. Power is supplied by a solar panel and rechargeable battery. The system intermittently converts methane into carbon dioxide and water vapor, significantly mitigating the greenhouse gas impact of enteric fermentation in ruminant livestock.