Albatrosses are famous for their long-lasting relationships. Many species form pairs that stay together for years—sometimes for life. So why would such faithful birds ever “divorce”?
In this episode, we explore a long-term study of black-browed albatrosses living in the Falkland Islands that reveals a surprising answer: the environment itself can push even the most loyal birds to split up.
Researchers followed hundreds of albatross pairs over 16 breeding seasons, tracking who stayed together, who separated, and what was happening in the ocean each year. They found that divorce was generally rare—about 3–4% of pairs per year—but it varied a lot depending on environmental conditions (see the yearly trends shown in Figure 2 on page 5).
As expected, birds were more likely to separate after a failed breeding attempt, especially if the failure happened early, before the egg hatched. But the biggest surprise was this: even pairs that had been successful were more likely to divorce during years when ocean conditions were poor.
In warmer years—measured by unusually high sea surface temperatures—the birds struggled to find food. These harsh conditions increased stress, raised the cost of reproduction, and made it more likely that females in otherwise successful partnerships would switch mates (illustrated in Figure 3 on page 6).
The takeaway is powerful: divorce in these birds isn’t just about picking a “better” partner. Sometimes, environmental stress disrupts relationships that would normally last, even when both partners are doing everything right. The study suggests that climate change may be quietly reshaping animal social systems in ways we rarely consider.
