Stuart Bullen: A diverse array of wildlife in parks

A nest in a tree
A nest in a tree

It’s the last days of April in the park.

An egg yolk yellow sun warms the relaxing families and couples; a delicate breeze refreshes pleasantly like an invigorating drink. All is peace and calm.

A shout disrupts the tranquillity. Everybody looks up or round. A group of homebound schoolgirls are running.

“It’s snowing!” they scream excitedly.

We look around and it’s true. The grass where these girls are running is covered in white. The girls themselves blurred to the vision in a blizzard of snowflakes.

We double take. Then the truth is revealed. It’s a spindrift of pure white blossom from the trees lining the path. The trees gently bough in the wind, throwing off their flowers to the ground like a snowfall. It makes for a surreal but beautiful interlude. But we get back to the job at hand.

For the past few weeks or so we have been following a family of treecreepers. These tiny birds with their white chests and speckled buff upper parts are very easy to overlook, being quite camouflaged. Some people have mistaken them for mice running up a tree trunk because of their quirky movements. As their name indicates, they can be seen scurrying up tree bark and scuttling around the branches. They creep up trees in a spiralling movement, using their stiff tail feathers as a support. They hang upside down off branches and can walk that way too. Treecreepers are quite addictive to watch, as they are one of the most gymnastic of our birds. They are not shy; more quiet and modest in habits, not brash or noisy like, say, a rook. At the same time, treecreepers are quite open in their habits and don’t seem to mind allowing human intrusion into their lives. In fact we got literally inches away from one pair’s nest on many occasions and seen them feed the chicks at almost eye height and it didn’t bother them.

This particular pair of treecreepers has a nest in an unbelievably small fissure in the bark of a lime. The entrance must be the size of a two pound coin, masked by soft bark and then hidden beneath the exoskeleton of ivy grasping the lime in a bear hug. It’s quite a feat of dexterity to watch as one quickly flies to within a centimetre or so of the entrance and then vanishes inside. Usually their nests have an exit hole as well as an entrance, but these two have just the one, which made viewing easier for us. Inside is a bed of tiny twigs and moss lining the cavity. They can produce a clutch of up to six eggs; when they hatch it must be quite claustrophobic in a treecreeper nest.

We watched as the male bird scurried up the tree in small hops, using his large scimitar shaped beak to forage for caterpillars, which he then passed on to the waiting female who, in turn vanished inside the nest to reappear seconds later to repeat the whole exercise again. Every now and again he would feed her the grubs, which she devoured hanging upside down. It’s interesting that a study carried out found that the males forage on the lower half of the trunk while the female uses the upper half of the tree. No one has yet been able to explain why. Whatever the reason, it helps to distinguish between the sexes, as they both look alike.

A liquid like laugh comes from up in the canopy of a horse chestnut tree behind us across the park.

Turning round we see a bolt of green shoot over our heads. A green woodpecker. Compared to our drab coloured treecreepers and other birds in the park, its bright red, yellow and green plumage makes it seem strangely exotic and out of place. The English parrot, a name given to it in one ornithological book, is quite apt. They are reasonably shy, more heard than seen. Seeing it bounce around on the grass, stopping occasionally to feed on ants, explains why this is unique among our other woodpeckers. The green woodpecker does all the other woodpeckery things as the other two breeds – drilling into trees and drumming with its beak, also breeding in holes in trees – but this one feeds primarily on the ground.

As its diet consists of ants, short and manicured grass areas are preferred hence their preference for parks. Using its 10cm long tongue, a third of the bird’s size which wraps in a coil around its skull, it probes the soil for ants. It can feed literally on a thousand or so ants at one sitting. In fact one Romanian study showed that woodpecker chicks ate an estimated 1.5 million ants each before fledging the nest!

It’s very easy to miss these birds when out walking the dog or crossing through the park as short cut back home or to the shops. But when you do see them it helps you to realise what a diverse array of wildlife can be found even in our local parks.

Stuart Bullen, of Bourne, trained as a biologist at the University of Sheffield and has worked in the media. He is passionate about nature and the environment and he has worked on various conservation projects with Natural England and other organisations.

When possible he likes to tramp around the local nature reserves and woods doing a spot of botany. He has recently qualified as a master gardener with Garden Organic.