How the robin keeps its secrets
Nature: Robins are very familiar - but they are also good at hiding their secrets. Mike Toms explains.
A few wisps of coarse grass, caught on the side of one of our ornamental conifers, are just enough to give away the location of a robin’s nest. Tucked between the sweeping, upwardly-curved branches, with their rich mat of flat needles, is a neat little nest containing three eggs. The female is still laying up and it will be another couple of days before the clutch is complete and she starts incubating. Fortunately for us the nest entrance faces the house, so the comings and goings of these surprisingly secretive little birds can be followed without them noticing.
The robin is one of the most challenging birds for those studying breeding behaviour; their nests can be placed on the ground or high up in a piece of ivy, cloaking a thick tree trunk. The nest itself is well camouflaged and the birds take care not to draw attention to its location. If a robin thinks it is being watched then it may drop the food it is carrying or even take it elsewhere in attempt to lead a would-be predator away from the vulnerable chicks.
One of the main methods used to find the nests of small birds is to watch adult birds carrying food back to the nest. While some species, such as willow warbler, allow the observer to get fairly close to the nest, you have to be fifty metres or more away from a robin before it ceases to view you as a threat.
Even when you know there is a robin nest within a few feet of you, they can be surprisingly difficult to spot. I remember a student nest recorder of mine, who called me over because he had had a small bird fly up from under his feet in the middle of a wood. There wasn’t any obvious cover, just a thick layer of oak leaves on otherwise bare ground. By laying down and looking across the ground, I could just make out the nest, tucked under a fallen branch covered with leaves – from above it was invisible! With luck, our robin eggs will hatch at the end of the month, and we’ll be able to watch the adults feeding the resulting chicks.