The change in habitat by part of the grey whale population "was probably due to oil and gas projects in Sakhalin," Alexandra Filatkina said, citing a chief whale researcher in the Far Eastern branch of Russia's Academy of Sciences.
Endangered gray whales have moved closer to Kamchatka, but they may not be safe there either, as environmentalists are concerned about planned oil production off the peninsula's western coast, Filatkina said.
Independent environmental studies have repeatedly indicated that noise, ship collisions, oil and gas spills, and habitat destruction due to oil and gas development are the main threats to the gray whales' survival. Experts have warned investors in the large-scale hydrocarbon projects in the region would be responsible for the extinction of the critically endangered species.
Russia unveiled on Wednesday its first liquefied natural gas (LNG) plant as part of the ambitious $20 billion Sakhalin-II oil and gas project, involving Royal Dutch Shell, Mitsui and Mitsubishi. Some 9.6 million metric tons of LNG will be produced annually, with the liquefied gas delivered from the plant in tankers.
Filatkina also said seven whales had died recently after being entangled in drift fishing gear and lobster traps in Russia's Pacific waters. She urged more government measures to protect whales.
The WWF welcomed on Tuesday a proposal by Russian Prime Minister Vladimir Putin to outlaw fishing with drift nets, which the group said came after "a lengthy campaign by fishermen and politicians in Kamchatka as well as local organizations, including WWF-Russia."
February 19 has been celebrated as world day of marine mammals protection since 1986, when commercial whaling was banned worldwide after ruthless whale hunting that lasted for 200 years.