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Impacts of Ocean Noise

Panel discussion at the African Bioacoustics Community around issues raised by Becoming Visible film

It’s been a productive week of raising awareness around the injustice of the bombardment of sound into the ocean by oil and gas companies prospecting with 3D and 2D seismic surveys. Thanks to Dr Simon Elwin and Dr Tess Gridley from Sea Search who organised the African Bioacoustics Conference this year for screening the Becoming Visible Documentary and then engaging an expert and balanced panel for further discussion and information around the complex issue of seismic surveys. 

Panel for the Impacts to Ocean Noise, African Bioacoustics Conference 2018 Dr Natacha Aguilar, Dave Japp, Janet Solomon, Prof Ken Findlay, Stet Mushwana, and chaired by Dr Jean Harris

Dr Natacha Aguilar from the Canary Islands discussed the impacts of sound and seismics on marine wildlife, especially beaked and pilot whales. She warned of the dangers of reflected sound that can intensify the effects and can explain the anomalies of animals further away from the airguns being more affected. She highlighted that the amount of man-made noise in the ocean is doubling every decade.

Prof Ken Findlay spoke about the Blue Economy and the importance of optimising ocean benefits without compromising ocean health. He spoke of National Capital Accounting, including triaging and trade-offs. Findlay raised questions around temporal and spatial exclusions regards seismic surveys and Marine Protected Areas. He asked how close should seismic surveys be allowed to these MPAs and raised the issue of buffer zones. He, too, questioned the efficacy of operational mitigation. He stated,”To me it is absolutely critical that reconnaissance surveys/ seismic surveys are brought back into the National Environmental Management Act and the National Environmental Oceans Act to ensure that the correct Environmental Impact Assessments are done.”

Dave Japp from Capricorn Marine Environment (which provides mitigatory service i.e. marine mammal observers and fishery observers to the oil and gas industry during the surveys) spoke of the challenges of minimising impacts to flora, fauna and fisheries. He raised the red flag of South Africa following the mitigations protocols of the JNCC standards, which were developed for the North Sea, but are applied broadly. These standards are however “modified to include more stringent standards of international best practice”. He said that RSA have to follow the acoustic and visual monitoring in a 500m mitigation zone around the airguns, which is a controversial point currently, but is a rule which has to be followed.

Stet Mushwana from the Petroleum Agency South Africa spoke of the history and current patterns of seismic exploration in RSA. He claimed the average size of 2D surveys range between 200 and 40 000km line length and that 3D surveys, to date, range from 500 to 14 000km in length. He also showed a slide of how much of ocean has been surveyed to date (red lines on map attached). 

Red lines indicate all the 2D +3D seismic survey lines completed on the RSA coast to date. During each line surveyed airguns exploded every 10 seconds for 24 hours a day. The average intensity per airgun explosion is 230dB.

He talked of the East coast as a ‘pioneer’ area. He said he “hoped that changes will come into effect” with regard to the reinstatement of the EIA process for oil and gas seismic/reconnaissance applications.

Q: Looking at the core of Operation Phakisa, a flawed fast-growth model from Malaysia: Can eco-tourism and renewable energy out-earn the potential of the offshore oil and gas industry that Operation Phakisa is exploring as economic development?
A: Ken Findlay: This is an interesting question because it goes to what you said about renewables. I talked about ecosystem services that are based on functional ecosystems – those values are lodged in renewables, compared to the environmental services where there is a limited, finite resource. This is one of the reasons why I opened with Johan Rockström’s Planetary Boundaries*. The really important thing here is we need to value, in these trade-offs across economic, social and environmental domains, that all three domains need to be looked at for decisions because what is of value economically might be outweighed by the intrinsic value, the bequest value, the existence value of a particular Marine Protected Area. What value do you do you put on a coelacanth? You know it hasn’t got an economic value. You can’t sell it on a market, but there are a lot of South Africans who really value that coelacanths are still in our waters. that’s something you can’t put a tangible value to and that’s what we’ve got to try and bring into the equation.

Q: In your opinion what is the best way to go about regulation of sound in the sea?As I understand it in both the National Environmental Management Act (NEMA) and the White Paper on National Environmental Management of the Oceanthe definitions of noise pollution is mainly attributed to how it is on land not necessarily how it is at sea. So do you think we should go along the route of making amendments to NEMA or what exactly do we need to do in terms of regulation and how would we therefore enforce any infringement in terms of noise pollution art sea wrt seismic surveys?
A: KF: An important thing is that there is such a wide ranging impact of noise on different species its very difficult to put a global cover on everything. It does however amaze me that we legislate under the Marine Living Resources Act that we may not watch a whale closer than 300m by boat, swimming or by aircraft, but that’s not to say we can’t pulse it out of existence in terms of acoustics. There’s nothing there. I think it is absolutely imperative that when we’re looking at NEMO or any ocean act that we consider these sorts of pollution aspects. Academia has a role to play in standards development, that then goes to legislation. Legislation is absolutely critical and at the back end of that there’s compliance monitoring and enforcement because without compliance monitoring and enforcement legislation is only as valuable as the piece of paper its written on.
Jean Harris:We can’t approach a whale closer than 300m but our boundary zone on seimics is 500m. Its an interesting concept in terms of how we view harassment and interruption of behaviour of species.
Natacha Aguilar: On land we have laws to prevent pollution that are based on human sensitivity to noise. At sea we based the first guidelines on the onset of hearing damage – temporary threshold shifts or permeant threshold shifts. thats where the 300m, 500m numbers came out. those are based on studies of captive dolphins exposed to sound and checking when they developed hearing damage. As our studies have continued we have seen that physiological damage other than hearing loss can be important for marine fauna and can be experienced even at great distances, indicating the effects of behaviour response – and that is difficult to put a law on because then you will be stopping ships and any seismics or any sonar…Governments could make it mandatory that they avoid duplication of surveys, for e.g. we have a map here of many areas having been surveyed already. Then there are competitive forces in the market that push to repeat a surveys with just a little bit better technology. So avoiding duplication of surveys would avoid a lot of unnecessary energy entering the ocean.
Janet Solomon: Based on Jean’s observation it is ironic to note that international guidelines (the Diving Medical Advisory Committee) for human divers in the water is 10km and more from the airguns*.
*International Marine Contractors Association reported that on a number of occasions diving had to be halted at around 30 km of separation. The reports strongly suggest that the 10 km distance quoted in DMAC 12 Rev 1 – Safe diving distance from seismic surveying operations as being an appropriate distance for the initiation of a joint risk assessment between all parties is “far too short.”,divers-find-seismic-ops-are-too-close-for-comfort_49662.htm


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