Bright birds make good mothers

Aug 13, 2013

Female blue tits with brightly coloured crowns are better mothers than duller birds, according to a new study led by the University of York.

Unlike humans, birds can see ultra-violet (UV) light. While the crown of a blue tit looks just blue to us, to another bird it has the added dimension of appearing UV-reflectant.

The three-year study of blue tits, which also involved researchers from the University of California Davis, USA and the University of Glasgow, showed that mothers with more UV-reflectant crown feathers did not lay more eggs, but did fledge more offspring than duller females. These brightly coloured mothers also experienced relatively lower levels of during arduous periods of chick rearing.

The results of the study are published in the journal Behavioral Ecology.

Author Dr Kathryn Arnold, from the University of York's Environment Department, said: "Previous studies have shown that male blue tits prefer mates that exhibit highly UV-reflectant crown feathers. Our work shows that this is a wise choice. UV plumage can signal maternal quality in blue tits, so a male choosing a brightly coloured female will gain a good mother for his chicks and a less stressed partner."

Funded by the Royal Society and the Natural Environment Research Council (NERC), the project was based in woodlands on the shores of Loch Lomond, Scotland and investigated the factors that affect breeding success in .

In blue tits (Cyanistes Caeruleus) both sexes exhibit bright UV-reflectant crown feathers. The birds are socially monogamous, with the female solely incubating the eggs and both parents feeding the chicks.

The researchers looked at the relative UV reflectance of the crown feathers of female and related this to indices of - lay date, clutch size, and number of chicks fledged - as well as the ' maternal state.

Dr Arnold said: "With up to 14 chicks to care for, blue tit mothers in our study were feeding their broods every couple of minutes. We showed that dowdy coloured females found this level of hard work twice as stressful compared with brighter mothers. Also, the mothers with more UV-reflectant crowns were highly successful, fledging up to eight more chicks than females with drabber feathers."

Explore further: Research shows impact of BMR on brain size in fish

Related Stories

Why are so many fairy-wrens blue?

Nov 01, 2012

(Phys.org)—Researchers have long tried to explain the enormous diversity in colour of birds, and a new study is giving insights into why the humble fairy-wren, a colourful Australian bird, is radiantly ...

Recommended for you

Bumblebees use nicotine to fight off parasites

1 hour ago

Researchers from Queen Mary University of London (QMUL) and Royal Holloway, University of London (RHUL), gave bumblebees the option to choose between a sugar solution with nicotine in it and one without. ...

ANZAC grevillea hybrid marks centenary celebrations

2 hours ago

Through an intense breeding program of native flora, Kings Park botanists have provided the Western Australian RSL with a commemorative grevillea (Proteaceae) in time for the Anzac Centenary.

Secret life of penguins revealed

5 hours ago

To mark World Penguin Day (25 April 2015) citizen science project Penguin Watch will release 500,000 new images of penguins and reveal secrets from a year of spying on penguins. ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.