Document ID: chunk:federal_register_of_legislation:F2024L00930:reg:2:p26
Version: federal_register_of_legislation:F2024L00930
Segment Type: reg
Provision Reference: reg 2 (pt 26/48)
Character Range: 132850–136035

mammals vary in hearing sensitivity and underwater noise in certain frequency ranges may impact marine mammal taxa differently (Southall et al. 2019). Much of the research attention on determining impact and threshold levels for regulation has focused on single exposure metrics to assess acute effects. Adverse effects of chronic sound sources (e.g. commercial shipping) at the individual, population, species' habitat, or ecosystem levels have not been incorporated into management decisions to the same extent as transient impulsive sound types (Ellison et al. 2012). Furthermore, there is currently a lack of understanding of the impacts from cumulative exposure from multiple sources of anthropogenic underwater noise on marine mammals and the appropriate frameworks for assessment (Faulkner et al. 2018).
The potential for impacts from anthropogenic underwater noise is of particular concern within or close to HCTS for southern right whales (i.e., reproduction BIAs) where whales, including pregnant and nursing females and calves, are resident for long periods (e.g., weeks to months). Marine mammals, such as southern right whales, rely on underwater sound to communicate. The range their sounds can be successfully detected can be limited by contributions of anthropogenic noise to the marine soundscape, which can mask the whale's underwater acoustic communication. Right whales have demonstrated increases in the amplitude of their upcall in response to increasing background noise levels, particularly in the frequency below 400 Hz, which is the range they use to communicate (Parks et al. 2010). As southern right whales recover from commercial whaling and their distribution and abundance increases, anthropogenic underwater noise may have the potential to disturb and/or deter southern right whales from occupying HCTS or currently unused but historically important areas.

    3.4.1     Industrial noise
Industrial noise, particularly from underwater construction activities arising from coastal and offshore developments, provides a potentially increasing threat to southern right whales and may interfere in their acoustic communication. The construction, operation and decommissioning of coastal and offshore developments, such as oil and gas platforms or floating processing facilities, marinas and ports, and marine renewable energy facilities, all create underwater noise from a wide range of activities. Development activities produce anthropogenic underwater noise as impulsive and non-impulsive sounds, including pile-driving, blasting, some forms of dredging, and sonar, that may be transient in nature whereas chronic industrial noise may include vessel noise (shipping and tender vessels) and operation of oil and gas facilities. There are also peripheral support activities, such as additional shipping traffic around marinas and ports and helicopter activity around oil and gas platforms to transport personnel. Most of these infrastructure projects require pile-driving during construction, which involves driving piles (beams or posts) into the seafloor to support the foundations of the structure. This creates strong (e.g. dependent on hammer energy;