28 September 2026: A study on spatial footprints of commercial whaling based on historic logbooks
A study by Freymueller and colleagues, titled “Historic logbooks reveal spatial footprints of commercial whaling”, was published in the journal PNAS in February 2026.
The bowhead whale was one of the most hunted whales between the 18th and 19th centuries, having been almost brought to extinction by the early 20th century. Whalers kept well-detailed logs of their expeditions and bowhead whale catch rates, especially the British and American fleets. However, little is known about how hunting effort was distributed through time and space. Such information is vital for understanding where bowhead whales were impacted the most, and the effects of whaling on bowhead whale population recovery.
Freymueller and colleagues combined data from whaling logbooks with statistical models to reconstruct daily locations for more than 700 bowhead whaling trips, between the years 1769 to 1914. This analysis allowed them to identify time and space trends in the bowhead whaling and understand the reasons behind them.
The results showed that whaling effort was heavily limited by sea ice coverage, with whalers operating mostly in areas of 10% to 30% sea ice coverage. Areas with deeper sea ice coverage where often inaccessible to whaling boats. This meant that some bowhead whale habitats were barely impacted by whaling and served as natural “protected areas” and population refugia.
The authors note that the bowhead populations with most refugia are currently the ones recovering faster (example, the East Canada–West Greenland stock, one of the populations which had greatest proportional extent of refugia). Meanwhile, the Sea of Okhotsk population lacked refugia, was the most heavily exploited population and is still failing to recover. Therefore, bowhead whale recovery is likely still being impacted to this day, by the effects of commercial whaling, which ceased a century ago.
You can read the full paper by Freymueller et al: https://doi.org/10.1073/pnas.2523917123
Photo credit: Fernando Ugarte