Are female starlings able to recognize the scent of their offspring?

• Published in: PloS one Vol. 9; no. 10; p. e109505
• Main Authors: Amo, Luisa, Tomás, Gustavo, Parejo, Deseada, Avilés, Jesús Miguel
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 09.10.2014; Public Library of Science (PLoS)
• Subjects: Alca torda; Animal behavior; Animal reproduction; Animals; Animals, Newborn; Biological evolution; Biology and Life Sciences; Birds; Brood parasitism; Choice Behavior - physiology; Discrimination; Female; Females; Gender differences; Glands; Nesting Behavior - physiology; Offspring; Olfaction; Olfactory discrimination; Olfactory discrimination learning; Olfactory stimuli; Parasitism; Progeny; Scent Glands - physiology; Secretion; Sexes; Smell - physiology; Social interactions; Starlings; Starlings - physiology; Sturnus unicolor; Uropygial gland; Spain
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0109505

Although there is growing evidence that birds may have individual chemical profiles that can function in several social contexts, offspring recognition based on olfactory cues has never been explored. This ability should be more likely evolved in colonial birds and/or species suffering brood parasitism, in which the risk of being engaged in costly misdirected parental care is high. We performed a choice experiment to examine whether females of the spotless starling, Sturnus unicolor, a species that is colonial, and where a fraction of the population is exposed to intraspecific brood parasitism, can discriminate between the scent of their offspring and that of unrelated nestlings. We also explored whether the development of the uropygial gland secretion may play a role in such olfactory discrimination by performing the choice experiments to females rearing nestlings of two different ages, that is, without and with developed uropygial glands. Results showed that female starlings did not preferentially choose the scent of their offspring, independently of whether the gland of nestlings was developed or not. Our results suggest that female starlings do not have or do not show the ability to distinguish their offspring based on olfaction, at least up to 12-14 days of nestling age. Further research is needed to examine whether odour-based discrimination may function when fledgling starlings leave the nest and the risk of costly misidentification is likely to increase.