The stability of methane hydrates at continental margins faces a significant threat from rising ocean temperatures. This scenario could potentially trigger the release of substantial (yet unconstrained) amounts of methane into the overlying water column and eventually into the atmosphere. Within marine sediments, the biologically mediated process of anaerobic oxidation of methane (AOM) is critical in mitigating such benthic methane discharge. However, AOM is not always ‘super’-efficient. There are two reasons why. First, some methane may pass the AOM biofilter, either by advection or migration through preferential permeable pathways. Second, methane-oxidizing microorganisms grow slowly, creating significant windows of opportunity for methane to escape into the ocean. Using a novel 1D multiphase reactive transport model, we investigate how potential methane emissions from climate-induced hydrate dissociation could impact AOM biofilter efficiency. We assess how multiphase methane transport dynamics control the methane accessible to the AOM community and examine the impact of AOM biomass dynamics on its ability to respond to sudden bursts of methane in marine sediments