A study by the Zoological Society of London and University of Cambridge looked at the effects of newborn nutrition on male plumage in rare New Zealand hihi.
Chicks that stock up on their five-a-day outshine their love rivals in later life, a new study shows.
Published yesterday (February 12, 2013) in Proceedings of The Royal Society B, the study reveals that male hihi birds develop more colourful and attractive breeding feathers if they receive a nest diet rich in carotenoids – natural pigments found mainly in fruit and vegetables.
Scientists from the Zoological Society of London (ZSL) and University of Cambridge looked at the effects of newborn nutrition on male plumage in the rare New Zealand hihi (Notiomystis concta) over the course of a year.
PhD student Leila Walker said: “We first hand-fed baby hihi birds either a carotenoid supplement – natural pigments used to colour yellow, orange and red – or a more complete dietary supplement. Then we looked at the effect this had on male breeding feather colour once those chicks had grown and moulted into their adult plumage.”
All nestlings initially develop female-like plumage and fledge at around one month old. Youngsters then moult their body feathers at about four months old, during which time the males obtain their breeding features. Colourful plumage is an important factor in a bird’s breeding success as it demonstrates the strong health of a bird to females.
ZSL research fellow Dr John Ewen said: “We saw that nestlings receiving more carotenoids were brighter as adults. This was a combined result of the carotenoid-rich dietary supplement they received, and the carotenoids they obtained as part of a natural diet fed to them by their parents.”
Research on hihi has highlighted how sensitive an individual’s life is to experiences faced as a nestling. Scientists are now gaining an idea of the information content of different plumage ornaments used in breeding. The next steps will be to manipulate these signals in adult birds to further test the effects on mating success.