U.S. Department of Commerce


Date of this Version



Published as Final Report, Sakhalin Energy Investment Company Ltd., February 2003.


Numerous species of marine mammals inhabit the Sea of Okhotsk. Two of the most endangered populations of large whales in the world; the Okhotsk Sea bowhead whale (Balaena mysticetus) and the western North Pacific (Okhotsk-Korean) gray whale are known to occur in this sea (Brownell et al., 1997; Clapham et al., 1999). Concerns regarding the status of these whale populations have been intensified by the onset of offshore oil and gas development programs in Okhotsk waters. Anthropogenic activities related to oil and gas exploration off the northeastern Sakhalin Island shelf include geophysical seismic surveying, drilling and production operations, waterborne discharges of a variety of materials, seafloor dredging, and vessel/aircraft traffic. These activities pose potential threats to the northeastern Sakhalin marine ecosystem and may impact the critically endangered western gray whale population that annually feeds there (Brownell and Yablokov, 2001; Weller et al., 2002a, 2002c). However, properly conducted biological monitoring can provide the requisite information needed to help prevent significant anthropogenic impacts, and in some cases, such as development of Habitat Conservation Plans (U.S. Fish and Wildlife Service, 1998), assist with mitigating unavoidable ecosystem impacts to acceptable levels. Studies in the U.S. and Canadian arctic or near-arctic, on bowhead whales, white whales (Delphinapterus leucas), and gray whales have demonstrated that knowledge of habitat use and behavioral reactions can help to plan industrial activities in a fashion that allows animals and human development to coexist (summaries in Würsig, 1990; Richardson and Würsig, 1995, 1997). Therefore, it has been recommended by the Russian and U.S. governments that biological investigations of potential industry-related ecosystem impacts off the coast of Sakhalin Island and elsewhere in Russia be conducted concurrent to oil and gas development projects (Anonymous, 1997).