Finches stressed by poor quality mates

Like many long-suffering wives, exasperated female finches feel the stress of being saddled with a poor quality mate, research has shown.

Monogamous Gouldian finches mate for life, but do not always end up with the most compatible partner.

Scientists observed how some females were forced to take what they could get after all the high quality males had been snapped up.

Tests showed these birds had stress hormone levels three to four times higher than the luckier females with good quality partners.

The response was rapid, occurring within 12 hours of initial contact, and lasted many weeks.

Being paired with a poor quality partner also had an effect on reproduction. Dissatisfied finches took significantly longer to lay their first eggs than those that were happier.

The Australian researchers, led by Simon Griffith, from Macquarie University, Sydney, wrote in the journal Proceedings of the Royal Society B: Biological Sciences: “Females that pair with poor quality partners do so on their own choosing, but the stress response we have demonstrated here reflects the internal conflict that underlies their decision – these females are making the best of a bad situation and are dissatisfied with their partner although he does represent a better option than not breeding at all.”

The researchers set up two experimental situations in which finches were either allowed to pair up naturally, or placed in “arranged marriages”.

In both cases, females finding themselves with mates they considered to be of poor quality experienced a rise in stress hormone levels.

Gouldian finches come in two varieties, with easily identifiable red and black heads.