Study
Hydrodynamic trail-following in harbor seals
Dehnhardt, Guido; Mauck, Björn; Hanke, Wolf; Bleckmann, Horst
Science, 2001
A harbour seal wearing a blindfold and headphones — removing vision and hearing — was released after a miniature submarine had travelled a winding path through the pool, and its track compared with the submarine’s. The experiment was repeated with the animal’s whiskers covered by a stocking mask.
- Studied in
- Phoca vitulina
- Sample size
- blindfolded harbour seals following a submarine’s wake
The blindfolded seal followed the submarine’s path accurately, including its turns, after delays of up to about thirty seconds. With the whiskers masked, it could not.
What it means
The authors' reading, and ours. Where they differ, that difference is the point.
How the authors put it
Harbour seals detect and follow hydrodynamic trails using their vibrissae, over delays long enough to be useful in tracking prey.
How NatureHQ reads it
A sense with no human analogue at all, demonstrated about as cleanly as it could be. A swimming fish leaves a wake that persists in the water for tens of seconds, and a seal reads it the way a dog reads a scent trail — the same information, in a different medium. The stocking mask is what makes it evidence rather than a nice observation: cover the whiskers and a seal that had been tracking accurately loses the trail entirely.
- A very small number of trained captive animals — the headline result rests on one seal.
- A submarine wake is more coherent and more regular than a fish’s.
- Establishes trail-following, not the range or persistence available in open water.
A blindfolded seal chasing a submarine that left thirty seconds ago
A fish leaves a wake in the water. Can a seal follow it after the fish has gone?
What this study is used for on NatureHQ
One study can inform several subjects. Here is everywhere this one is cited.
The lateral line
Fish carry a row of receptors along the body that detects water moving nearby. Nothing touches them and no sound arrives — it is a sense with no human equivalent.
The lateral line
A swimming fish leaves a disturbance in the water that lasts for tens of seconds. A blindfolded seal can follow it with its whiskers, turns and all.
Published by: American Association for the Advancement of SciencePublished in Science or Science Advances (AAAS).
doi.org/10.1126/science.1060514
Checked against Crossref on 2026-09-28, and they agree on the title, the authors and the year.
NatureHQ summarises research in its own words and does not reproduce published text. Reviewed 2026-09-02.