At the top of the food chain sit predators like us. But we’re not keen on competition when it comes to securing our food supply. The same is true of other predators and a common solution is to eat your way out of the problem. It is always good to have a theoretical hook to hang the observed behavior on, though.
There is even a handy dandy term for eating your fellow predators. It is termed intraguild predation. The current theory hooks used by the predatory bird cognoscenti are that the predators are trying to remove competitors, they are feeling pressure on their food supply and the one that is of interest today is that they are simply trying to remove predators so that in future they can go about their normal business and not come back to find the bones of their babies scattered to the four winds.
Lourenço et al in the current issue of Behavioral Ecology and Sociobiology tried to check the theories out with a set of raptors. There was sufficient food, so we can put food stress on the back burner for special occasions. They arranged realistic, but stuffed, eagle owls (predator/competitor) and a stuffed tawny owl (competitor) out by their nests.
Nobody cared about the tawnies but the eagle owls were severely harassed, so we are left with eat your predator before he/she eats you. This is clearly a case of super mob rule. We see crows mobbing buzzards and the like, but it must be more satisfying to feed juicy tidbits of someone who was trying to eat you to your brood. It sounds like the plot line of many of our movies!
