Study
Experiments on bird orientation
Kramer, Gustav
Ibis, 1952
Starlings showing migratory restlessness were kept in circular cages from which only the sky was visible, and their preferred direction recorded. Mirrors were then used to deflect the apparent position of the sun.
- Studied in
- Sturnus vulgaris
- Sample size
- caged starlings in circular orientation cages
Birds oriented in a consistent direction when the sun was visible, shifted their heading by the angle the mirrors deflected the sun, and lost directional preference under complete overcast.
What it means
The authors' reading, and ours. Where they differ, that difference is the point.
How the authors put it
Migratory birds take a compass bearing from the position of the sun.
How NatureHQ reads it
The experiment that made orientation a laboratory science rather than a field observation, and the first of the manipulations this whole subject is built on: change one cue, and see whether the animal changes with it. The mirror is what makes it an experiment — a bird that merely prefers a direction on sunny days has shown nothing.
- One species, in cages, during migratory restlessness rather than in flight.
- A sun compass alone gives direction and not position, and says nothing about how a bird knows which direction to want.
Moving the sun with mirrors, and watching a bird turn
Is a restless caged bird actually using the sun, or merely doing better on sunny days?
What this study is used for on NatureHQ
One study can inform several subjects. Here is everywhere this one is cited.
Published by: Wiley journalsPublished in a Wiley journal.
doi.org/10.1111/j.1474-919x.1952.tb01817.x
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 2026-09-03.