Blue Whale Migration

When these happened

29 dated records from 1904 to 2027. Each is drawn as wide as its date is certain — a band is a band because nobody knows the year, not because the drawing is imprecise.

29 shown · 29 dated · 0 cannot be placed on an axis · Approximate or contested. Draw a band and do not sharpen its edges.

In order29

1909 or c.1912 (sources disagree)The longest blue whale on record is measured at South Georgiasources disagree about the date
Sources disagree, or the dating is contested. Stated, not resolved.
1904-11-16Whaling begins at Grytviken, South Georgia
It happened, and the record is settled.
1925The factory ship Lancing takes a stern slipway south
It happened, and the record is settled.
1930/31 seasonThe Antarctic blue whale catch reaches its all-time peak
It happened, and the record is settled.
1946-12-02The International Convention for the Regulation of Whaling is signed
It happened, and the record is settled.
1947-03-20The heaviest blue whale on record is weighed
It happened, and the record is settled.
1960s-2000sBlue whale song frequencies are observed falling worldwide
It was measured or witnessed, with the observation cited.
1965 (Grytviken); island operations described as running to 1971Whaling ends at South Georgia
It happened, and the record is settled.
1966The IWC protects blue whales from commercial hunting
It happened, and the record is settled.
1948-1970sSoviet fleets take protected whales and file false returns
Sources disagree, or the dating is contested. Stated, not resolved.
1982The IWC adopts the commercial whaling moratorium
It happened, and the record is settled.
1986 (coastal); 1985/86 pelagic seasonThe commercial whaling moratorium takes effect
It happened, and the record is settled.
1989The 52 Hz call is identified in Navy hydrophone data
It was measured or witnessed, with the observation cited.
1991The SOSUS mission is declassified
It happened, and the record is settled.
1993Satellite tagging of eastern North Pacific blue whales begins
It happened, and the record is settled.
1994The Southern Ocean Whale Sanctuary is adopted
It happened, and the record is settled.
1994The true scale of Soviet whaling is published
It happened, and the record is settled.
1996-07-19Bahia de Loreto National Park is established
It happened, and the record is settled.
1999Tagged whales confirm the Gulf of California as a wintering ground
It was measured or witnessed, with the observation cited.
2011The energetics of blue whale lunge feeding are modelled
It happened, and the record is settled.
2013, 2015, 2019Dedicated Antarctic Blue Whale Project voyages
It happened, and the record is settled.
2014Pygmy blue whale movements between Australia and Indonesia are published
It was measured or witnessed, with the observation cited.
2015Eastern North Pacific blue whales are estimated near carrying capacity
It happened, and the record is settled.
2020-02Blue whales are found back at South Georgia
It was measured or witnessed, with the observation cited.
2021-11Baleen whale consumption is re-measured, and the krill paradox sharpens
It happened, and the record is settled.
2023The only published Antarctic blue whale satellite tracks are released as data
It was measured or witnessed, with the observation cited.
2025 season (reported 2026)California voluntary speed reduction reports its 2025 season
It was measured or witnessed, with the observation cited.
2025A capture-recapture abundance estimate for Antarctic blue whales is published
It was measured or witnessed, with the observation cited.
2026An individual Antarctic blue whale is re-sighted at South Georgia
It was measured or witnessed, with the observation cited.