The Great Spotted Woodpecker: Both A Hero And A Villain

A visit by a great spotted woodpecker to a bird table or hanging feeder is always something of an event, especially in June when the red capped youngsters may come along too. Woodpeckers are dramatic birds, bold black and white and red, and their entrance inevitably has a sense of drama about it. When the woodpeckers land, the smaller birds often hang back, or even scatters, seemingly nervous of that mighty bill.

Earlier in spring, that same long, chisel like beak is put to other uses. From January onwards it is hammered very rapidly into a sonorous piece of wood to make a pleasing 'drumming' sound, the equivalent of a song. And it is also used throughout the year as a heavy tool for excavating holes. This is the woodpecker's great talent: it makes holes in the trees from scratch, making new homes, where before there were none. It makes them for a nest cavity, and for a roosting hideaway, adding new models again and again.

The woodpecker often chooses to work on wood that is slightly rotten. It will hack away steadily, like a labourer might use a pickaxe. It's heavy work. After a week or two of intermittent effort the woodpecker will have made a substantial cavity, and so it starts working from the inside rather than the outside. By the end of the excavation the wood chips are gathered in the bill and tossed dismissively out of the new home.

It takes a very special bill to wreak this kind of destruction upon rotten, or sometimes even upon live wood. That bill is also used for chipping wood-boring insects into view, or for ripping off bark, whatever it takes to provide a diet of arboreal invertebrates. A woodpecker would hardly be a woodpecker without it.

And, if you think about it, a wood would hardly be a wood without a woodpecker either, at least in ornithological terms. Where, for example, would the tits breed, and the flycatchers? Many other birds besides woodpeckers rely on tree holes for their nesting sites, and the rest cannot excavate them for themselves. They depend on the woodpeckers to do it for them. If it were not for the activities of the carpenters of the bird world, all these species would be hard pressed to find breeding sites at all.

In view of this, one might think that woodpeckers would be among the most welcome of all birds around the woodland or garden scene. And yet, when birds such as tits come across great spotted woodpeckers in the breeding season, they repeatedly mob them aggressively. They fly towards the woodpecker, call loudly and try to drive the unwanted visitor away- perhaps away from a hole that, ironically, the source of their rage initially created itself.

One wouldn't expect a bird such as a tit to be clever enough to recognise the woodpecker and thank it politely for constructing its nest site, but such a reaction does seem puzzling. Until, that is, you realise that the great spotted woodpecker, despite its positive effect on bird populations, also has a dark side.

It's too easy, you see: a bill adapted for ramming through wood to find invertebrates can very easily be put to a different investigative use. Should a woodpecker develop a taste for bird meat, it would have no trouble at all in finding some. In the average wood or garden there are plenty of occupied holes with nestlings in them in spring, just waiting there ready to be eaten, uniquely accessible to a hunter with a pickaxe. And this is exactly what happens.

A great spotted woodpecker is an adaptable bird, and may be seen to hunt nestlings in several ways. The commonest technique is the logical progression from its usual feeding routine. It detects nestlings by ear as they call from their chamber at the bottom of the hole, and then it simply drills straight through to them. Within minutes the small bodies can be dragged through the newly created gap, one by one. In the second technique, a woodpecker lands close to the nest hole and the nestlings. The nestlings then, upon hearing the arrival of a bird outside, eagerly jump to the entrance as they always do, hoping to be the first to reach the expected parental food delivery. But they are met at the entrance by the woodpecker, and ironically become a food delivery themselves.

In many areas, including gardens, great spotted woodpeckers have also quickly recognised that nest boxes are also excellent and reliable sources of nestling meat. They are easier to get into than tree holes too, with thin sides and a vulnerable entrance holes that can be quickly enlarged for forced entry. Predation by woodpeckers appears to have increased in Britain as more and more of these intelligent birds have cottoned on. You could almost say that great spotted woodpeckers are the new magpies, with disturbingly similar plumages and tastes.

There are, however, more concrete solutions to this problem than offered by the magpie controversy. Well, not quite concrete I suppose in a literal sense, but instead 'woodcrete'. This tough substance, a mix of wood chippings and concrete, is the basic constituent of many new (and inevitably expensive) nesting boxes and provides a safe haven for younger chicks. An older method, that of placing a metal plate around the nest entrance, was effective for deterring the woodpeckers from forcing their way in from the entrance, but never prevented their more determined operations to drill through the side. Now, perhaps, nest boxes made of less penetrable material will eventually cause the box raiding habit to decline.

And if it does, great spotted woodpeckers will be raised to home grown hero status again, at least in the garden environment.