Do sandhoppers use the skylight polarization as a compass cue?

• Sandhoppers are well known for their sun compass orientation mechanism.
• We provide evidence of polarized light sensitivity in Talitrus saltator.
• Skylight polarized light was not used as a cue for menotactic orientation.

Investigations carried out in the 1950s on the use of polarized light by sandhoppers as a compass reference did not reach convincing results. Therefore, polarized light compass orientation in the sandhopper Talitrus saltator seems to be a traditional attribute more than a solid demonstration. Our tests carried out under artificial and natural conditions of illumination using different polarizing and neutral density (grey) filters demonstrated that T. saltator perceives polarized light; however, it does not use the skylight polarized light as a cue for menotactic orientation. However, since the sky spectral and luminance gradients were not completely eliminated in our tests, a possible influence of these two celestial factors of orientation could still be present. Therefore, we conclude that this species, in this experimental paradigm at least, does not use a polarized light compass mechanism, despite a very good sun compass system of orientation.