Dominic Couzens reveals the truth behind the 'aggressive' robin.
There's a truly wild bird behind the "friendly" façade of a robin. I'm not referring to its famous aggressive nature, I'm referring to the fact that your garden robin isn't a pet living on handouts. It needs to make a living and the way it has evolved to do this, away from human eyes, is what has made the robin the bird it is.
Robins eat invertebrates such as beetles, earwigs and ants, found on the ground and on the woodland floor. They don’t dig for these or turn over leaf-litter, instead they must wait until the creepy-crawlies show themselves on the surface – in other words, until the prey makes a mistake. When robins perch on spades they are watching the ground below for food to break cover, and then they pounce upon it.
They also feed by hopping along the ground, hoping to cross paths with moving prey. For this sort of patient feeding to work, robins need privacy and a lack of disturbance. And for this they need a territory. If they don’t defend their territory vigorously, their foraging will keep being disrupted and they will starve.
So, robins cannot tolerate intrusive competitors and must sometimes fight them to the death. Dunnocks often feed in similar shady corners to robins and are summarily evicted.
Even wood mice have been attacked by robins trying to forage. People, though, present opportunity for robins. By tilling the soil while gardening, human beings unearth an army of invertebrates into the open. That’s robin heaven; no wonder they are tame!
Robins might be aggressive but they prefer to avoid conflict if they can. It can be costly, in energy and potentially dangerous injury, so they fill the autumn and winter air with songs, their voices flagging up ownership of the territory.
The song might sound pleasing to us, but its message to other robins, male and female, is simply "keep out". If a stranger ignores the vocal warning, the red breast is also a permanent "keep out" visual signal.
The song message does change, however, between December and March.
The males start singing from more elevated perches and may use shorter phrases, now with the primary intention of attracting a mate.
If a female is interested she must trespass into the male's territory, running the gauntlet of a male's natural aggression, and the male may go on the attack before he realises that it's a welcome incursion.
If the misunderstanding is sorted out, pairing may occur, but even if it does, the two birds won't start breeding until March or April.
