Study
Adaptation of sperm whales to open-boat whalers: rapid social learning on a large scale?
Whitehead, Hal; Smith, Tim D.; Rendell, Luke
Biology Letters, 2021
Digitised logbooks from nineteenth-century American whaling voyages in the North Pacific were analysed for strike rate — the proportion of whales sighted that were successfully harpooned — over the first years of exploitation of a naive population.
- Studied in
- Physeter macrocephalus
- Sample size
- digitised logbooks from 19th-century North Pacific whaling voyages
Strike rate fell by roughly 60% within a few years of whaling beginning in the region. The decline is too rapid to be explained by selective removal of vulnerable individuals or by genetic change, and the whales' defensive behaviour shifted from the anti-predator response effective against orcas — bunching at the surface — to swimming fast upwind, away from sailing vessels.
What it means
The authors' reading, and ours. Where they differ, that difference is the point.
How the authors put it
Sperm whales learned socially, and rapidly, to counter a novel threat, with information spreading between social units faster than individual experience could account for.
How NatureHQ reads it
A remarkable use of an archive. Whaling logbooks were kept for commercial reasons, and they happen to record exactly what is needed: how many whales were seen and how many were caught, ship by ship, in a population encountering hunters for the first time. The collapse in strike rate over a few years is too fast for evolution and too widespread for individual learning, and the recorded change in behaviour — from a formation that works against orcas to fleeing upwind, which is the one thing a sailing ship cannot follow — is specific to the new threat. It is also, unavoidably, a reconstruction from records kept by people with other priorities, which is the honest limit on how hard to lean on it.
- Logbook data were recorded for commercial purposes with inconsistent definitions of a sighting.
- Whaler skill and equipment also changed over the period, which could contribute to strike-rate change.
- Social transmission is inferred from the rate of spread, not observed.
Reading whale behaviour out of nineteenth-century account books
Did sperm whales learn how to evade whalers, and did they learn it fast enough to rule out evolution?
What this study is used for on NatureHQ
One study can inform several subjects. Here is everywhere this one is cited.
Published by: The Royal SocietyPublished by the Royal Society.
doi.org/10.1098/rsbl.2021.0030
This reference was resolved automatically against Crossref on 2026-08-11.
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