The ‘2013 code of conduct for minimising acoustic disturbance to marine mammals from seismic survey operations’ (the Code) has different requirements for seismic surveys depending on the total combied operational capacity of the acoustic source (DOC 2013). Level 2 surveys are marine seismic surveys whose acoustic source has a total combined operational capacity 2.50–6.99 litres or 151–426 cubic inches. For details on level 1 surveys, please see www.nzlevel1seismicsurveys.co.nz. Level 3 surveys (acoustic sources <2.49 litres or 150 cubic inches) are exempt from the Code.
Level 2 surveys are lower-scale seismic surveys, most often carried out for scientific research.
For a general overview of the Code, please see www.codeofconductseismicnewzealand.co.nz
PRE-SURVEY PLANNING & MARINE MAMMAL IMPACT ASSESSMENTS
Before conducting any level 2 surveys, a Marine Mammal Impact Assessment (MMIA) must be submitted to the Director-General of Conservation. For details on what an MMMIA must include, please see www.marinemammalimpactassessment.co.nz
Additional requirements may be necessary when planning and conducting surveys in Areas of Ecological Importance (AEI; www.areasofecologicalimportance.co.nz), which includes Marine Mammal Sanctuaries (MMS; www.marinemammalsanctuaries.co.nz).
MMO & PAM REQUIREMENT FOR LEVEL 2 SURVEYS
For level 2 surveys, there must be two Marine Mammal Observers (MMOs) on-board the seismic vessel, with at least one on watch during daylight hours while the acoustic source is in the water. For level 2 surveys, Passive Acoustic Monitoring (PAM) is optional, but may become a requirement in the future. If PAM is used there must be two PAM Operators on-board, with at least one on watch at all times.
During level 2 surveys, crew may act as MMOs and PAM Operators, as long as they are trained and experienced, as per the Code. Please see www.nztrainedobserver.co.nz and www.nzqualifiedobserver.co.nz for more information.
SEISMIC OPERATIONS WITHOUT A PAM SYSTEM
If PAM malfunctions or becomes damaged during a level 2 survey, seismic operations may continue while repairs are carried out or the PAM system is replaced.
If PAM has not been incorporated into a level 2 survey, extra provisions must still be met when conducting seismic surveys during poor sighting conditions. Poor sighting conditions are defined as night time, or daylight hours when visibility is <1.5 km or sea state is ≥ Beaufort 4. The requirements during poor sighting conditions are:
- That no more than three marine mammal-instigated shutdowns or delays have occurred in the previous 24 hours of active survey operations in good sighting conditions (i.e. good sighting conditions during the daylight hours in the last 24 hour period, not a cumulative 24 hours of good sighting conditions); or,
- If seismic operations have not been carried out in the previous 24 hours, MMOs must have been looking for, and not seen any, marine mammals within a 20 nautical mile radius of the proposed start-up position for at least the last two hours of good sighting conditions.
DELAYED STARTS & SHUTDOWNS
Detections (visual or acoustic) of marine mammals in the relevant mitigation zones during level 2 surveys call for a delay in the activation of the acoustic source. The acoustic source is shutdown when a species of concern (www.speciesofconcern.co.nz) is detected in the relevant mitigation zone.
|DOC (2013) 2013 Code of conduct for minimising acoustic disturbance to marine mammals from seismic survey operations.|
|p. 36. Publishing Team, Department of Conservation, Wellington, New Zealand.|