Babysitting birds help elderly warbler parents raise their young

Jan. 19 (UPI) -- These days, most parents could use a little babysitting help. Elderly Seychelles warblers may not have pandemic fatigue, but they too require a bit of help raising their young.

According to a new study published Tuesday in the journal Evolutionary Letters, cooperation among group of Seychelles warblers ensures older parents get plenty of assistance.

The newly published data showed warbler young born to aging parents fare better when parental duties are shared.

For 30 years, scientists kept tabs on the health of groups of warblers living on a small island called Cousins Island in the Seychelles, located off the east coast of Africa in the Indian Ocean.

Researchers observed how parental duties were shared in different groups of Seychelles warblers, while also tracking the survival rates of offspring.

"In many animal species, offspring from aging parents do not survive as well as offspring from younger parents," study co-author David Richardson, said in a news release.

"The cooperative nature of Seychelles warblers means care for offspring is often shared between the dominant breeding pair and a variable number of adult subordinate helpers that help with various aspects of rearing, including providing food for the offspring," said Richardson, a professor of biological sciences at the University of East Anglia.

Researchers found warbler young aren't the only ones that benefit from such an arrangement.

When younger warblers help older parents, mom and dad aren't quite so taxed with the physical demands of parenthood.

"Lower parental investment can improve the parents own survival and future reproductive output," Richardson said.

Mortality rates among young increase with the age of the mother bird, but the latest research found assistance from younger adult birds helped to mitigate this effect.

Researchers found female moms who had recruited more help over the course of their lifetime fared better than aging moms with less help. Cultivating a larger cooperative group pays dividends.

"Such late-life fitness benefits of breeding cooperatively lead to the prediction that older parents should be more inclined to recruit helpers to improve their both their own survival and that of their offspring," said lead study author Martijn Hammers, lecturer of ecology and evolution at the University of Groningen in the Netherlands.

The researchers suggest their findings provide further proof that all kinds of species, including humans, benefit from living in groups and sharing parental duties.