THE SHELL LEAKS FILES: 11 SEPTEMBER 2026

SLF-2007-054

The Sakhalin Papers XLIV: The Whales Moved — What the 2015 Data Eventually Revealed

The airguns stopped in 2015. The scientific argument did not. Seven years later, a series of peer-reviewed studies finally put numbers on what happened to western gray whales during the unprecedented seismic season off Sakhalin. The results resist both convenient extremes. The whales did respond: their local density fell as accumulated seismic and vessel noise increased, and individual animals changed movement and breathing behaviour. The researchers concluded explicitly that mitigation had not eliminated short-term behavioural responses. Yet models examining reproduction predicted little or no effect from the 2015 disturbance scenario, 14 calves were identified the following year, and the wider population continued its long-term recovery. The evidence therefore supports neither “no impact” nor “population damage proved.” It supports something scientifically more difficult: measurable disturbance, mitigation that reduced but did not eliminate response, and unresolved population-level consequences.

Archive reference: SLF-2007-054
Collection: The Sakhalin Papers
Principal scientific records: Glenn Gailey et al., Gray whale density during seismic surveys near their Sakhalin feeding ground; Glenn Gailey et al., Western gray whale behavioral response to seismic surveys during their foraging season, Environmental Monitoring and Assessment, 2022
Supporting scientific record: Lisa Schwarz et al., Gray whale habitat use and reproductive success during seismic surveys near their feeding grounds, 2022; Lisanne Aerts et al., Seismic surveys near gray whale feeding areas off Sakhalin Island, Russia: assessing impact and mitigation effectiveness, 2022
Contemporaneous scientific record: Western Gray Whale Advisory Panel Statement of Concern, 8 May 2015
Authenticated Shell record: Royal Dutch Shell plc Sustainability Report 2015
Subsequent conservation record: IUCN, 3 September 2016 and 24 April 2019
Court record: Export Credits Guarantee Department v Friends of the Earth [2008] EWHC 638 (Admin), used solely for the earlier Sakhalin II environmental and public-finance context
Evidence standard: Statistical association is distinguished from proof of injury or population-level causation. Observed behaviour is distinguished from modelled demographic consequences. Population recovery is not treated as proof that industrial disturbance was harmless. Industry financial and logistical support for parts of the research programme is disclosed rather than ignored. read more