An appropriate post to mark the end of pancake-gorge-fest and the start of Lent? Perhaps not: in this case, the sexiness of male hihi (Notiomystis concta) has everything to do with what they ate – but as nestlings, not adults!
Cambridge PhD student Leila Walker, in collaboration with Dr Becky Kilner and Dr John Ewen at ZSL, hand-fed hihi chicks a normal diet, or one supplemented with carotenoids, pigments found in plant cells which occur naturally in the hihi diet of nectar, fruit and invertebrates. Boosting intake of carotenoids in nestlings resulted in brighter plumage as adults, and, as in many bird species, fancy feathers leads to greater mating success.
And, unfortunately for the hihi, mating success is just what this bird needs. They are listed as vulnerable by the IUCN and occur naturally in only one small island population in New Zealand. A team of hihi researchers is leading a concerted conservation effort, including reintroducing populations to the mainland to boost numbers, and supplementing the diet of wild hihi.
That’s where Leila’s work comes in. Here’s a great example of where behavioural ecologists and conservationists could join forces. By conducting studies in this way of what diet will produce the best offspring and guarantee high mating success, behavioural scientists could help to restore the numbers of this lovely little bird.