Great tits show early signs of splitting up, providing social clues to bird ‘divorce’

In a discovery that deepens our understanding of animal social ties, a study led by researchers from the University of Oxford in collaboration with the University of Leeds has shown that large wild breasts have clear behaviors signaling the “divorce” well before the breeding season. The results, published in Acts of the Royal Society BProvide new valuable information on how animals are sailing complex social decisions.

For monogamous birds which only bind with a partner at the same time, the choice of a companion has a critical impact on the success of reproduction. Previous studies have examined why certain monogamous birds remain with the same partner while others “divorce” before the next breeding season. What remained clear, however, is how their daily social ties during the non-reproduction season indicate a future fraction.

Finding the first divorce clues would be very difficult to explore for most birds of birds. However, the new study took advantage of the data from the Wytham Woods Great Tit Project, one of the most studied wild bird populations in the world, which has been taking place for more than 75 years. This allowed researchers to generate robust quantitative data on social interactions between individual birds.

In a fascinating way, the data showed that the first signs of divorce could be identified in winter, months before couples reproduce with different partners the following spring. This suggests that winter socialization during the non-reproduction season is indicative of what will be seen in the next mating period.

Key results:

• Winter behavior can predict spring divorce. Pairs that separated later spent much less time together during the winter than those who remained faithful.
• The faithful pairs are increasingly linked over time, while the divorce pairs have become more distant – even on visiting feeders at different times.
• Birds heading towards a split rarely preferred to socialize with their reproductive partner – unlike the faithful birds, the link of which was reinforced over time.

Senior researcher, Ph.D. The candidate Adelaide Daisy Abraham (Department of Biology, University of Oxford), said: “Our results show that bird relations are far from static. We have found a clear behavioral signature during the winter months which can predict the probability of a pair of divorce in the spring. The divorce seems to be a socially motivated process, routing over time.”

To assess the social associations of birds, the researchers recorded how they behaved around the food stations equipped with the advanced RFID technology (radiofrequency identification). These feeders have automatically detected tiny electronic labels transported by birds in the study, recording their presence. This allowed researchers to generate high -resolution data sets for each individual, map the birds with which they have associated with feeders.

This data was compared to the information on which the birds had formed pairs together during the previous and following reproductive seasons. The results have clearly shown that the faithful of large wild breasts visited the feeders with their reproductive partners much more often than the pairs that have divorced.

Professor Ben Sheldon (Department of Biology, University of Oxford), Wytham study chief, noted: “This work is an important step towards the discovery of social mechanics behind the bond and loyalty of pairs in nature. Our study revealed that it is possible to use behavioral dynamics in pairs of wild animals to predict future social states, such as divorce.”

Following the same birds over several years, the study links the way in which partnerships are formed, persist and break away during the seasons. This offers rare information on the life cycle of social relationships in a wild animal and linked to the pair, and could now guide future work in other species. In addition, as the revealing signs of divorce are now identified, researchers can use it to investigate the causes and consequences of divorce as they take place.

The main author, Dr. Josh Firth (University of Leeds), said: “Following these individual birds through the seasons and for many years allow us to see how relationships are formed and decompose in nature in a way that short -term studies would not do so. In the future, carrying out new experiences in nature will offer even more possibilities of understanding the dynamics of the obligation and separation in time.”