Newly Poly Plover Dad Still Figuring Out His Time Management | Defector

"An estimated 90 percent of birds are socially monogamous, meaning they choose partners with whom they cohabitate and raise young, albeit usually without the bounds of sexual exclusivity. For many birds, monogamy just makes sense. Their tiny, naked chicks are essentially helpless, and the round-the-clock care they require is an easier job for two."

"The small and skittish white-faced plover is one such monogamous bird. Pairs of white-faced plovers switch off the incubation of their nests. The females sit on the nest by day, and the males take over at night. Around noon, when temperatures are hot, both parents will pitch in to cool the eggs."

"In 2024, for reasons that remain unknown to anyone but him, he found another female plover with whom he felt an instant connection. But in this case, both female plovers knew about each other. Early that spring, they each laid three eggs into the same nest. All the eggs were fertilized by the male."

While approximately 90 percent of bird species are socially monogamous, most other animals practice multiple partnerships. Birds typically adopt monogamy because their helpless chicks require round-the-clock care from two parents. White-faced plovers exemplify this pattern, with females incubating eggs during the day and males at night, switching duties during hot afternoons. This system has sustained the species for thousands of years across eastern Asian shores. However, in 2024, a male plover on a Chinese island deviated from this norm by simultaneously maintaining relationships with two females. Remarkably, both females were aware of each other and laid three eggs each into the same nest, with all eggs fertilized by the same male.

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