OVERVIEW

The northeastern shelf of Sakhalin Island in Russia has large proven oil and gas reserves. It is also home to many marine species, including a population of endangered gray whales. The Western Gray Whale Advisory Panel (WGWAP)1, established through an arrangement between Sakhalin Energy Investment Company, Ltd2 and IUCN, seeks to help minimize the potential impacts of exploration and production activities on gray whales in this rapidly industrializing area. A comprehensive and integrated planning, assessment, monitoring, and mitigation program for a marine seismic survey conducted in 2010 was carefully developed through collaboration between the WGWAP and Sakhalin Energy.

A MODERN APPROACH TO CONDUCTING MARINE SEISMIC SURVEYS

IN SENSITIVE AREAS

Seismic surveys employ loud pulses of sound to image the geological structure of the seabed. A specific environmental concern is the potential impact on marine animals that rely on sound (e.g., for orientation and communication). In 2010, a large-scale seismic survey was carried out to assess hydrocarbon reserves near a key feeding area for gray whales off the Sakhalin coast. With the potential risks of disturbance and/or physical harm to the whales, the survey was preceded by a lengthy planning process3. The planning and implementation of this survey and the analysis of biological data obtained from the monitoring and mitigation program followed a comprehensive, interdisciplinary, integrated approach. The rationale and design of the approach are described briefly here.

BASELINE MONITORING AND PLANNING

The biology, behaviour, and population trends of western gray whales in the Sakhalin area have been studied by Russian and international collaborations of academic and private sector researchers, including members of the WGWAP and Sakhalin Energy advisors, since 1995. This provided a robust baseline of scientific understanding, which is essential for responsible planning of any large seismic survey. The primary mitigation measures to reduce risks were to (1) limit the timing of the survey (to as early as possible in the ice-free season) in order to minimize overlap between noise-generating activities and the seasonal presence of whales on the feeding grounds and

(2) optimize the spatial extent and configuration of the survey so that the needed geological data could be obtained with the smallest possible acoustic footprint. Additionally, a number of real-time monitoring technologies were deployed in combination with operational procedures to keep whale exposure to seismic noise below specified response thresholds.

MONITORING AND MITIGATION

The environmental protocols developed collaboratively and implemented by Sakhalin Energy had two purposes, the primary one being to minimize impacts on the whales in real time (mitigation) and the secondary one to analyze responses after the survey was completed (monitoring). Elements of the overall monitoring and mitigation strategy included:

(1) Archival acoustic recording of natural and human-generated sounds before, during, and after the survey;

(2) Sound propagation modelling and in situ verification of acoustic footprints around operations in relation to important whale habitat areas;

(3) Real-time measurements of sounds produced during the survey and strict adherence to specific operational protocols based on received sound levels;

(4) Shore-based visual detection of whales using scan sampling techniques;

(5) Shore-based monitoring of movements and behaviour of individual whales using theodolite tracking; and

(6) Vessel-based visual detection of whales by onboard observers with direct authority to call for specific changes in operations (including shut-down) based on whale proximity and behaviour.

Data from these integrated program elements were used to manage the seismic survey in real time with the dual objectives of minimizing impacts on whales in the area, while at the same time completing the survey as rapidly as possible in order to reduce the temporal overlap with whale presence. An example of a real-time operational protocol was the implementation of shutdown criteria when whales were observed in precisely defined areas expected to be ensonified at predetermined threshold levels.

DATA ANALYSES

Data and information collected by the visual and acoustic monitoring teams were integrated with corresponding data and information on the location and nature of survey operations. Multivariate statistical analyses were used to consider the timing and location of whales before, during, and after the survey, both generally and in terms of inferred responses by individuals.

OPERATIONAL AREA & INTEGRATED MONITORING

1 http://www.iucn.org/wgwap2 http://www.sakhalinenergy.ru/en/aboutus.asp3 http://www.iucn.org/wgwap/wgwap/task_forces/seismic_survey_task_force/

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Conceptual map showing the seismic survey zone relative to the western gray whale feeding area off Sakhalin Island. Near-shore contours of 163dB rms underwater sound level from the seismic source (behavioural disturbance threshold) were modelled for all survey lines. Data collection stations for acoustic recording and visual observation of whale behaviour and distribution were used for monitoring and mitigation.

LESSONS LEARNED AND IMPLICATIONS

Gray whales were seen in the area before, during, and after the survey, which was completed on schedule. The most critical aspects of survey planning and implementation were efforts to reduce the acoustic footprint of the operation – for example, limiting noise levels by making the survey area as small as possible, and decoupling the timing of the survey from the whales’ peak feeding period. The use of multi-disciplinary, integrated teams to monitor both the survey operations and the whales, with specific operational protocols tuned to the biology and behaviour of the animals, represented a significant advance in the planning of a seismic survey in an environmentally sensitive area. This successful collaboration between Sakhalin Energy and the WGWAP used the best available scientific information and an integration of modern remote sensing technologies to plan for and complete a large-scale industrial activity while striving to minimize impacts on a potentially vulnerable marine species. Hopefully, the lessons learned, both in general and specific to each element of monitoring and mitigation, will inform the planning and conduct of future seismic surveys off Sakhalin and in other sensitive habitats.

ABOUT THE WGWAP

Since 2004, IUCN has worked with Sakhalin Energy in order to provide advice and recommendations on how the company can minimize risks associated with its operations on the Western Gray Whales and their habitat. As one part of this broad initiative, in 2006 IUCN created a panel of independent scientists – the Western Gray Whale Advisory Panel (WGWAP) – which provides scientific advice and recommendations on the company’s operational plans and mitigation measures.

ABOUT IUCN

IUCN, International Union for Conservation of Nature, helps the world find pragmatic solutions to our most pressing environment and development challenges. IUCN works on biodiversity, climate change, energy, human livelihoods and greening the world economy by supporting scientific research, managing field projects all over the world, and bringing governments, NGOs, the UN and companies together to develop policy, laws and best practice.

IUCN is the world’s oldest and largest global environmental organization, with more than 1,000 government and NGO members and almost 11,000 volunteer experts in some 160 countries. IUCN’s work is supported by over 1,000 staff in 60 offices and hundreds of partners in public, NGO and private sectors around the world.

Marine Seismic SurveysModern Approaches to MinimizingRisks in Environmentally SensitiveAreas - Sakhalin Case Study

FURTHER INFORMATION

Website: www.iucn.org/wgwap/Contact: Global Marine and Polar Programme, marine@iucn.org

INTERNATIONAL UNION FOR CONSERVATION OF NATURE

WORLD HEADQUARTERSRue Mauverney 28 1196 Gland, SwitzerlandTel +41 22 999 0000Fax +41 22 999 0002www.iucn.org INTERNATIONAL UNION FOR CONSERVATION OF NATURE

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