To appropriately design mitigation measures across the whales' geographic range, it is crucial to identify the whales' wintering areas and migration routes, and assess their spacio-temporal overlap with threat factors such as fishing gear, vessel traffic and industrial activities.

The International Whaling Commission (IWC) Scientific Committee and various panels convened under the auspice of IUCN have proposed repeatedly that satellite telemetry is an efficient way to investigate the migration routes and wintering grounds of western gray whales. Scientists have been cautious about tagging these whales, however, because of the population's very low numbers.

To ensure that a telemetry programme is carried out in the safest possible manner, a Scientific Steering Group (SSG) was established to provide advice on research protocols, study design and measures to be taken to minimise the risk of negative effects on individuals or the population as a whole. The final set of protocols used during the 2010 satellite tagging research programme ensured consistency between advice provided by the IWC Scientific Committee and the IUCN Western Gray Whale Advisory Panel (WGWAP).

The satellite tagging got the green light in June 2010, and in late August a field team, comprising scientists from the US and Russia, embarked on its expedition to the Sakhalin Island region to locate and tag whales. Logistical challenges and bad weather conspired to thwart their efforts, even though some 25 males were sighted and approached. Finally, on the last day of the expedition, the team managed to tag an adult male gray whale. The tagged whale, known as ‘Flex’, has been seen regularly in the Sakhalin area in summer since it was photographed as a calf in 1997. The team has been following its movements via satellite on a daily basis since the tagging with data beamed from the transmitting tag. Flex stayed at Northeast Sakhalin until around mid-December, but instead of moving south as expected, he moved across the Okhotsk Sea to the west coast of Kamchatka, then followed the coast around the southern tip of Kamchatka and up along the east coast to the Commander Islands, across the Bering Sea towards Alaska, through the Aleutian Island chain and across the Gulf of Alaska. At the beginning of February 2011 Flex arrived at the US west coast off Washington State.

In 2011, for the second consecutive year, an international team of scientists successfully tagged endangered western gray whales off the coast of Russia. The research team tagged six whales and is now tracking the animals via satellite.

Updated map and information on the tagged whales’ migration paths is available here:

This research is conducted by A.N. Severtsov Institute of Ecology and Evolution of the Russian Academy of Sciences (IEE RAS) and Oregon State University Marine Mammal Institute in collaboration with the U.S. National Marine Fisheries Service and Kronotsky State Nature Biosphere Reserve. The research is contracted through the International Whaling Commission (IWC) and International Union for Conservation of Nature (IUCN) with funding from Exxon Neftegas Ltd., Sakhalin Energy Investment Company Ltd. and Mrs Maja Hoffmann.