A scientific team has studied the variation in the yellow coloration of the iris of the European owlet (Athene noctua) and scops owl (Otus scops).

The piercing gaze of an owl is a unique thing in the world.

Birds show a great variability of color patterns involved in your communication. However, among these striking features, the function of the eye color. Until now, a possible role in signaling, in pair recognition or in the camouflage.

“The iris color is a very striking feature in the mostly cryptic design of many species of owls and could therefore play a role in their communication based on chromatic signals, a possibility not yet sufficiently explored in this group of birds ”, explains Arianna Passarotto, lead author of the study and pre-doctoral researcher at the Arid Zones Experimental Station (EEZA) of the Higher Council for Scientific Research.

In this work, led by the EEZA researcher Jesus M. Avilés, have observed the variation in the yellow coloration of the iris in the european owl (Athene noctua) and the scops owl (Otus scops) to check if this trait could be an indicator of the quality of the animals in a context of parent-child communication or in another social context.

In the study, published in Journal of Raptor Research, have verified that adults exhibit more intense yellow coloration than chickens. However, the color of the iris does not differ between the two sexes in the two species.

In the owl, the yellow color of the irises of the chickens seems to be more related to the quality of the parents. On the other hand, in scoundrel chickens they have not found any relationship with the indicators used. In adults they have found a positive relationship between nest success and iris color in the females owl, but not scops.

Therefore, scientists suggest that the yellow coloration of the iris is unlikely to play a role in parent-child communication in these two species, however it could play a role in a social context in the Little Owl.

“The owl is a monogamous species with a very territorial behavior, therefore, the color of the iris could play a role in the deterrence between conspecific. However, this possibility needs to be explored in more detail in future studies ”, concludes Passarotto.