If you think you know all about the birds and the bees, think again.
Bumblebees can intimidate birds into abandoning their nests and even to abandoning their eggs, researchers in South Korea have shown.
The experiments, conducted by Seoul National University’s laboratory of behavioural ecology and evolution, studied the interactions between bees and Oriental and Varied tits on the slopes of the Gwanak mountain. They found the bees’ warning buzz, coupled with their conspicuous colouring, enabled the diminutive insects to steal the freshly built nests from their much larger predators. The study observed bumblebees present in more than a fifth of the nest boxes they recorded.
The birds, natural hunters of the bees, were found to be significantly distressed if they came upon a bumblebee in their freshly built nest boxes.
Bumblebees are known to require cavities for nesting, and can use abandoned nests of other animals. However, bumblebees invading freshly built nests are a relatively modern finding, the scientists said.
The research, lead by Piotr Jablonski, showed that when a small speaker emitting a bee buzzing noise was placed in the tits’ nest, alongside a dead bumblebee glued to an upright toothpick, the birds often abandoned their nests.
These findings are novel as there has been very little research done on understanding this type of competition between prey and predator, the authors write. They believe it is possible that “the warning auditory signals not only help bumblebees in competition with their avian predators but also in competition for cavities with [a] variety of other animals”.
The research is published online in Behavioral Ecology & Sociobiology.