Recent developments regarding Marine Mammal Acoustic Technical Guidance
On 24 October 2024, the United States' National Marine Fisheries Service (NMFS) published a peer-reviewed update to their Technical Guidance for Assessing the Effects of Anthropogenic Sound on Marine Mammal Hearing.
The updates include new information and changes to noise exposure criteria that are commonly referenced by titleholders in underwater sound impact assessments in Australia.
Specifically, the updates include changes to the auditory weighting and exposure function parameters for marine mammal hearing groups, as well as thresholds for the onset of auditory injury and temporary threshold shift (TTS) in marine mammal hearing for non-impulsive and impulsive sound sources.
The evaluation and prediction of impacts from acoustic emissions should be supported by the best available science (i.e. relevant, applicable, contemporary, peer-reviewed and published by reputable sources) and appropriate impact threshold criteria.
The updated NMFS technical guidance is contemporary published scientific information that proponents and titleholders should consider in their assessment of underwater sound impacts and risks under the Offshore Petroleum and Greenhouse Gas Storage (Environment) Regulations.
Proponents and titleholders with permissioning documents soon to be submitted or currently under assessment should review the updated NMFS technical guidance and consider how it may affect the outcomes of their impact or risk assessments, or the selection or effectiveness of control measures.
For permissioning documents that have already been accepted by NOPSEMA, proponents and titleholders should apply processes within their implementation strategy for the activity for review of new information and management of change, as appropriate.
Proponents and titleholders may discuss their specific circumstances with NOPSEMA to understand potential regulatory implications of any proposed approach/es to considering and addressing the new information.
A copy of the NMFS 2024 technical guidance can be accessed via the NMFS website.