The Bureau of Land Management funded a project to investigate the potential impacts to fish from seismic exploration employing vibroseis was conducted in Spring 2003. The project was designed to help address agency and local resident concerns that vibroseis seismic activities occurring on or near bodies of water harboring wintering fish may have the potential to injure or kill fish. The project was supported by the seismic exploration company WesternGeco.
The first phase of the project included placing fish in cages below the ice of a lake without fish and exposing them to various levels of pressure generated by the vibroseis equipment. Two experimental groups of fish were exposed to vibroseis pressure and two control groups were processed. Necropsies were conducted on all fish and each was X-rayed to identify any organ, soft tissue or skeletal injuries.
The second phase of the project, once it had been determined that lethal effects were not likely, was to measure the disturbance response of naturally wintering fish in a pool in the Sagavanirktok River. Underwater cameras were set-up in an area of with several hundred fish and a vibroseis vehicle was operated above the fish in a fashion similar to routine field operations. The vehicle produced pressure impulses several times to test if fish became desensitized to the pressure input. Fish were disturbed and fled the area of origin of the pressure source but returned after a short of time. Fish were notably less disturbed by the pressure input after the initial one or two events.
Final results from this effort are published in DNR/OHMP Technical Report 05-02 (PDF 2,066 kB)