Adaptive Management Approach to Oil and Gas Activities in Areas Occupied by Pacific Walrus

During Shell’s 2015 exploration drilling program in the Chukchi Sea, activities were conducted in accordance with a Letter of Authorization issued by the United States Fish and Wildlife Service that allowed the incidental harassment of Pacific Walrus and Polar Bears under the Marine Mammal Protection Act. As a part of the request for authorization, Shell proposed a process to monitor and assess the potential for activities to interact with walruses on ice, especially if ice posed a potential threat to the drill site. The process assimilated near real-time information from multiple data sources including vessel-based observations, aerial surveys, satellite-linked GPS tags on walrus, and satellite imagery of ice conditions and movements. These data were reviewed daily and assessed in the context of planned activities to assign a risk level (low, medium, or high). The risk level was communicated to all assets in the field and decision makers during morning briefings. A low risk level meant that planned activities could occur without further review. A medium risk level meant that some operations had a greater potential of interacting with walrus on ice and that additional discussions of those activities were required to determine the relative risk of potential impacts compare to the importance of the planned activity. A high risk level meant that the planned activities were necessary and walrus on ice were likely to be encountered. Assignment of a high risk level triggered contact with agency personnel and directly incorporated them into the assessment and decision making process. This process made effective use of relevant available information to provide meaningful assessments at temporal and spatial scales that allowed approved activities to proceed while minimizing potential impacts. More so, this process provides a valuable alternative to large-scale restriction areas with coarse temporal resolution without reducing protection to target species.