The Afrikaaners named it Spookvoël, and so it is. Seldom seen even by 'the African rustic' its three mournful, ventriloquial and tremulous whistles, each lasting almost a second: "hoawwww ... hoawwww ... hawwwwip", repeated every minute or so, have been the ornithological highlights, these past two weeks, in our 'wildness garden' on the western edge of little Arusha - the safari city.
This ghostly whistler arrives, at more or less the same time each day, mid-morning. First it calls out to us its version of "trick or treat" from somewhere above the big red gate at the southeast corner of the driveway. Then the spook enters and proceeds to haunt the garden for about an hour moving, virtually unseen, from one Silver Oak to another. Each tree is festooned with wild creepers, a variety of yellow-flowering african cucumbers for the most part, which have sneaked-up this past wet season into the very topmost branches. The sorrowful whistling follows a fairly fixed circuit of the property each day, so an ambush is possible.
A long, leaf green bird shape, owner of the ghoulish voice, is best observed during the midday lull in its garden tour, an intermission, when he or she comes to the lowest branches of the Cardinal´s Hat, our biggest and most glorious red flowering Malva (hibiscus), that flourishes right outside the window of my wife Elsie´s consultation and reiki room. Here it joins the smaller birds gathered there, and after preening for a short while, hops down to the ground, apparently without causing too much of a fuss among the bulbuls and sunbirds, firefinches and sparrows.
On the ground, in the shade of the bush, the 25cm length of this grey, gold and green Gladiateur de Blanchot (the man was governor of Senegal at the turn of the eighteenth century) is a seriously hefty representative of the gimlet-eyed, yet soft plumed of back, Malaconotidae.
This is an extremely good-looking, largely carnivorous family within the great Corvoidea, the second largest radiation of the passerines, the greatest single bird order. A spectacular endemic family with equally splendid names, evoking the lands and islands of the greater Africa: Bush-Shrikes, Puffbacks, Tchagras, Boubous (Gonoleks), Helmet-Shrikes, Batises, Wattle-Eyes and the wonderful Vangas of Madagascar.
At close range, through the open window, the golden staring eye of Malaconotus blanchoti quickly catches one's own. Until with growing respect, one appreciates some detail in that fearsome beak, large and heavy-looking, black, robust, strongly-hooked and bluntly notched with six bristles each side (two nasal, four rictal); clearly this is a predator to be reckoned with. A terrifying adversary were you suddenly miniaturised into some small bush dwelling creature.
Although insects and invertebrates usually make up the majority of its diet, this Bush-Shrike will catch and eat anything which it can subdue. Snakes of up to 75 cm have been seen to be attacked; one bush-shrike was watched dragging a snake for over six metres, and over a twenty minute period, before finally abandoning it uneaten.
The Grey-headed Bush-Shrike is typically a bird of well-wooded bush land, occurring at low densities (maybe one pair per 200 or 300 hectares), that only infrequently occupies gardens. We hope that its daily appearance in our garden, and its appearance in that of our friends, Anabel and Geoff Harries, who live three kilometres distant, beyond the Nairobi road and across Burkha coffee farm, might be a normal cold-season phenomenon around Arusha. Doubtless the birds are venturing here (and there) in search of food, at this the leanest time of the year, when accessible invertebrates are in their least active period. Perhaps in this season the bush-shrikes maintain a larger non-breeding range adjacent to and more extensive than their nesting territory. In which case might it be possible that these two birds are members of a pair, or of a breeding group, for cooperative brood-raising is more than likely in this bird?
Or perhaps these birds are being driven to spend an hour or more in the somewhat contrived and artificial 'wildness' of our garden by the relentless incremental degradation of the landscape all around us. The travel-driven economy booms, and the human population of Arusha increases day by day, so that the little city is bursting at the seams. Individuals of other bush land birds are appearing around the garden now and then, they reside near us a while, yet many disappear after only a few days or weeks, presumably either dying or moving-on; our garden nature reserve being simply too small, or too isolated, to provide them with the food resources they require. If one is a birder-naturalist, as I am, one has to salvage some interest, granted it is often bittersweet, from the increasingly degraded ecology of the excessively humanised landscapes of our times.
Today I watched with interest 'our bird' hopping on the ground, wrestling a cigar shaped stick in bill, a thick indigenous stick no less, one that arrived in a seed-filled sack of moist earth, gathered under a grove of lofty native trees. Trees that protect the fresh water springs of Burkha, our nearest coffee farm, and protect the non-breeding resort of two rare migrants - Malagasy Pond Herons. The stick had been placed with the earth beneath that Cardinal´s Hat to encourage a more natural ground flora in our garden. Eventually the bush-shrike hopped out of view, beyond the dry and weeded earth, stabbing at an exposed rootlet, briefly examining a little tangle of alien-herb-allowed, searching, always searching, for anything edible.
Some ten minutes later it reappeared, up in the tree tops, trying to rip open the tightly-woven dome of one of two active Baglafecht Weaver nests, which hang from an end branch of the biggest, most creeper-draped Grevilea in the northern hedgerow, not 20m from our bedroom window. It might have already eaten something on that branch, since before I could grab my binoculars, I saw it holding something down, a nestling-sized item, holding it with a strong left foot, tearing it apart. Moments later it was leaning out, and hanging head-down, from the same branch in an attempt to reach into the entrance of the outermost weaver nest; but it was skillfully and quickly driven-off by a very accurate swooping aerial attack, hitting the centre of its back, by one of the female 'Baglafechts'.
A not very distant relative of blanchoti was named the Bulo Burti Boubou (Laniarius liberatus). Known form only a single individual who was discovered in October 1988 hiding in the acacia trees and bushes, in the garden of a Somali district hospital, a garden overgrown with creepers and climbers, which sounds not unlike ours. Liberatus was so-named because it was never killed for science. No type specimen was taken. Instead it was captured in January 1989 and flown to Europe, for questioning, in a mitochondrial DNA manner of speaking! Eventually it was returned to Africa, yet not released until March 1990, in Balcad nature reserve further south in central Somalia, and a long way from the erstwhile hospital in Buulo-barde.
It seems that the hospital gardens in which it was discovered, surrounded by ever more degraded land, had become the only sanctuary for this little liberatus, and these were no longer tenable. Previously this had been a temple or sacred grove by virtue of the humanity being manifest there; the few trees being spared the fuel cutter's axe, which was laying waste to all the lands beyond the fence.
Destruction of the fabric of the living land was a prelude to the collapse of humane society, in late twentieth century Somalia, as surely as it has been elsewhere. The ecological message is perfectly clear. Just as liberatus was no sooner found than lost, amidst the destruction of the riparian woodlands of Somalia, and the ensuing chaos there, so our liberty and freedoms will ebb away should we become any less capable of recognizing, cherishing and defending these our sacred groves.