For many people, rain is not very pleasant. But for some birds, rain has far more catastrophic consequences than having to cancel a picnic. This is the case for a small species known as the “Seychelles warbler” or “Seychelles warbler”, which is much more likely to divorce after periods of excessively low or high rainfall, according to one new study published on November 11, 2024 in the Journal of Animal Ecology.
Thus, these upheavals could well transform their tropical paradise into matrimonial hell. If, said like that, this discovery may make you smile, in reality, it above all indicates that climate change could have considerable repercussions on the reproduction of a certain number of species throughout the world, as Newsweek explains.
Seychelles reed warblers are socially monogamous, meaning that a male and female form a long-term pair over a long period of time – usually several breeding seasons, or even a lifetime. Social monogamy is observed in around 90% of bird species, and when this bond is broken without one of the partners dying, it is called divorce.
During the study, researchers analyzed sixteen years of mating behavior of Seychelles reed warblers on Cousin Island, and compared it to weather conditions during that same period. They found a striking correlation between this species’ divorce rate and fluctuations in precipitation, with more divorces in years when precipitation was abnormally low or high compared to years when precipitation was moderate.
Rainfall is associated with divorce in the socially monogamous Seychelles warbler..
Read the full paper here: @AgusBentlage @Frigg_Speelman pic.twitter.com/M4FF8gajaT— Journal of Animal Ecology (@AnimalEcology) November 21, 2024
How to explain it? “This result could result from the impact of rain on reproductive success, as it affects food availability and parental trade-offs between investment in current and future reproductive success”write the scientists. In other words, extreme weather conditions, whether flood or drought, have a major impact on the species. Nests destroyed, habitats damaged, thermal regulation undermined… All this physiological stress seems to compromise the stability of the links.
A wider problem
That said, researchers found no direct link between the likelihood of divorce and reproductive success or the number of offspring produced, meaning there are likely other factors at play influencing the divorce rate. But in the face of a rapidly changing climate, these results are very worrying for the Seychelles warbler, a species already facing conservation challenges.
The researchers call for considering these results in a broader context: as climate change only intensifies, other socially monogamous bird species could also be affected. “This research not only improves our understanding of animal behavior in the face of climate variability, but also provides valuable information that could inform conservation efforts for species vulnerable to the effects of climate change,” concludes Frigg Speelman, co-author of the study and doctoral student in behavioral ecology at Macquarie University, Australia.
Source: www.slate.fr
