Aromatic plants in nests of the blue tit Cyanistes caeruleus protect chicks from bacteria.
Several bird species add fresh fragments of plants which are rich in volatile secondary compounds to their nests. It has been suggested, although never tested, that birds use fresh plants to limit the growth of nest microorganisms. On Corsica, blue tits (Cyanistes caeruleus) incorporate fresh fragments of aromatic plants into their nests. These plants do not reduce infestation by nest ectoparasites, but have been shown to improve growth and condition of chicks at fledging. To understand the mechanisms underlying such benefits, we experimentally tested the effects of these plants on the bacteria living on blue tits. Aromatic plants significantly affected the structure of bacterial communities, in particular reducing bacterial richness on nestlings. In addition, in this population where there is a strong association between bacterial density and infestation by blood-sucking Protocalliphora blow fly larvae, these plants reduced bacterial density on the most infested chicks. Aromatic plants had no significant effect on the bacteria living on adult blue tits. This study provides the first evidence that fresh plants brought to the nests by adult birds limit bacterial richness and density on their chicks.
Mennerat
Adèle
A
Centre d'Ecologie Fonctionnelle et Evolutive, CNRS, UMR 5175, 34293 Montpellier Cedex 5, France. adele.mennerat@bio.uib.no
Mirleau
Pascal
P
Blondel
Jacques
J
Perret
Philippe
P
Lambrechts
Marcel M
MM
Heeb
Philipp
P
D000818:Animals; D001419:Bacteria / Q000254:growth & development*; D001424:Bacterial Infections / Q000517:prevention & control / Q000662:veterinary; D005260:Female; D008297:Male; D009425:Nesting Behavior / Q000502:physiology*; D009812:Odorants; D046109:Passeriformes / Q000145:classification / Q000382:microbiology / Q000502:physiology*; D010944:Plants / Q000737:chemistry*; D014835:Volatilization