Study
Cephalopods as prey. III. Cetaceans
Clarke, Malcolm R.
Philosophical Transactions of the Royal Society B: Biological Sciences, 1996
Squid beaks recovered from cetacean stomachs were identified to species and counted, since beaks resist digestion and their size predicts the size of the animal they came from, allowing diet to be reconstructed quantitatively.
- Studied in
- Physeter macrocephalus, Cephalopoda, Architeuthis
- Sample size
- squid beak counts from cetacean stomachs across decades of sampling
Sperm whale diet is dominated numerically by medium-sized squid, with individual whales holding hundreds to thousands of beaks. Giant squid beaks occur but form a very small proportion of the total. Estimated global cephalopod consumption by sperm whales is very large in aggregate.
What it means
The authors' reading, and ours. Where they differ, that difference is the point.
How the authors put it
Sperm whales are primarily predators of abundant mid-sized cephalopods; the largest squid are an occasional rather than a staple prey.
How NatureHQ reads it
The beak count is what makes this quantitative, and it demolishes the picture people carry. A sperm whale is not hunting giant squid; it is eating a very large number of ordinary ones, roughly the size of a forearm, in the dark, at depth. Giant squid do turn up in the counts and are eaten, so the encounters are real. But they are a rounding error in the diet, which makes the recurring image of the epic battle a story about a rare event told as though it were the animal's job. Sucker scars on sperm whales are real too, and they mostly grow with the whale rather than recording a recent fight.
- Beak accumulation over-represents species with hard beaks and long residence times.
- Most material comes from whaling-era stomachs, unevenly sampled by region and season.
- Beak size to body size relationships are estimated and carry error.
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/rstb.1996.0093
This reference was resolved automatically against Crossref on 2026-08-11.
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