Wandering albatrosses (Diomedea exulans) are known to some as the most romantic birds on Earth. A recent study published in the journal Royal Society Biology Letters has revealed that bolder males of this species are likely to get and keep mates. This paper is notable because it’s the first to show a link between personality and divorce in the species.
Researchers with the Woods Hole Oceanographic Institution (WHOI) utilized data from long-term studies conducted on Possession Island in the Southern Indian Ocean. They found that bolder males were more able to keep their mates when other males attempted to usurp them.
These love birds are known to mate for life, but sometimes “forced divorces” occur because of Possession Island’s high female death rate, partially due to conflict with commercial fishing. Consequently, many male widowers are looking for a new mate; some of these males simply try to steal a female from another male.
“In instances of forced divorce, bolder individuals are more likely to guard their partner. Shyer individuals tend to avoid risks and engaging in antagonistic interactions with intruders,” explained lead author Ruijiao Sun, a Ph.D. candidate with the MIT-WHOI joint program. “Breeding is very costly to wandering albatross. So individuals have to make a trade-off between reproduction and their own survival.”
The researchers analyzed data from a 54-year monitoring program to carry out their study. They also conducted their own experiments, which included approaching albatrosses and observing their reaction to human or novel object presence. If the male birds were marked as bold if they called or stood up, they were deemed shy if they had little to no response.
Although fascinating, this phenomenon may not occur with albatross populations that have more breeding females since there would be less competition for partners.
“Divorce can sometimes be adaptive, to gain a better partner or offspring. But in the case of forced divorce, there is no benefit to future reproduction,” explained Stéphanie Jenouvrier, a WHOI biologist, Sun’s advisor, and senior author of the paper. “We were able to study the impact of personality on divorce only because we had access to incredible long-term data sets combining demography and personality for this population.”
By Erin Moody , Earth.com Staff Writer