The hoopoe (Upupa africana) is a colourful bird found across Afro-Eurasia, notable for its distinctive `crown` of feathers. The hoopoe is a medium sized bird, 25-32 cm (9.8-12.6 in) long, with a 44-48 cm (17-19 in) wingspan. It weighs 46-89 g (1.6-3.1 oz). The species is highly distinctive, with a long, thin tapering bill that is black with a fawn base. The strengthened musculature of the head allows the bill to be opened when probing inside the soil. The hoopoe has broad and rounded wings capable of strong flight; these are larger in the northern migratory subspecies. The hoopoe has a characteristic undulating flight, which is like that of a giant butterfly, caused by the wings half closing at the end of each beat or short sequence of beats. In what was long thought to be a defensive posture, hoopoes sunbathe by spreading out their wings and tail low against the ground and tilting their head up; they often fold their wings and preen halfway through. They also enjoy taking dust and sand baths.
Habitat and Distribution
The hoopoe is widespread in Europe, Asia, and North Africa, Sub-Saharan Africa and Madagascar. Most European and north Asian birds migrate to the tropics in winter. In contrast, the African populations are sedentary all year. The species has been a vagrant in Alaska. Hoopoes have been known to breed north of their European range, and in southern England during warm, dry summers that provide plenty of grasshoppers and similar insects, although as of the early 1980s northern European populations were reported to be in the decline, possibly due to changes in climate. The hoopoe has two basic requirements of its habitat: bare or lightly vegetated ground on which to forage and vertical surfaces with cavities (such as trees, cliffs or even walls, nestboxes, haystacks, and abandoned burrows) in which to nest. These requirements can be provided in a wide range of ecosystems, and as a consequence the hoopoe inhabits a wide range of habitats such as heathland, wooded steppes, savannas and grasslands, as well as forest glades. The Madagascar subspecies also makes use of more dense primary forest. The modification of natural habitats by humans for various agricultural purposes has led to hoopoes becoming common in olive groves, orchards, vineyards, parkland and farmland, although they are less common and are declining in intensively farmed areas. Hunting is of concern in southern Europe and Asia. Hoopoes make seasonal movements in response to rain in some regions such as in Ceylon and in the Western Ghats. Birds have been seen at high altitudes during migration across the Himalayas. One was recorded at about 6,400 m (21,000 ft) by the first Mount Everest expedition.
The diet of the hoopoe is mostly composed of insects, although small reptiles, frogs and plant matter such as seeds and berries are sometimes taken as well. It is a solitary forager which typically feeds on the ground. More rarely they will feed in the air, where their strong and rounded wings make them fast and manoeuvrable, in pursuit of numerous swarming insects. More commonly their foraging style is to stride over relatively open ground and periodically pause to probe the ground with the full length of their bill. Insect larvae, pupae and mole crickets are detected by the bill and either extracted or dug out with the strong feet. Hoopoes will also feed on insects on the surface, probe into piles of leaves, and even use the bill to lever large stones and flake off bark. Common diet items include crickets, locusts, beetles, earwigs, cicadas, ant lions, bugs and ants. These can range from 10 to 150 mm in length, with a preferred prey size of around 20-30 mm. Larger prey items are beaten against the ground or a preferred stone to kill them and remove indigestible body parts such as wings and legs
Hoopoes are monogamous, although the pair bond apparently only lasts for a single season, and territorial. The male calls frequently to advertise his ownership of the territory. Chases and fights between rival males (and sometimes females) are common and can be brutal. Birds will try to stab rivals with their bills, and individuals are occasionally blinded in fights. The nest is in a hole in a tree or wall, and has a narrow entrance. It may be unlined, or various scraps may be collected. The female alone is responsible for incubating the eggs. Clutch size varies with location: northern hemisphere birds lay more eggs than those in the southern hemisphere, and birds at higher latitudes have larger clutches than those closer to the equator. In central and northern Europe and Asia the clutch size is around 12, whereas it is around four in the tropics and seven in the subtropics. The eggs are round and milky blue when laid, but quickly discolour in the increasingly dirty nest. They weigh 4.5 grams. A replacement clutch is possible. Hoopoes have well-developed anti-predator defences in the nest. The uropygial gland of the incubating and brooding female is quickly modified to produce a foul-smelling liquid, and the glands of nestlings do so as well. These secretions are rubbed into the plumage. The secretion, which smells like rotting meat, is thought to help deter predators, as well as deter parasites and possibly act as an antibacterial agent. The secretions stop soon before the young leave the nest. From the age of six days, nestlings can also direct streams of faeces at intruders, and will hiss at them in a snake-like fashion. The young also strike with their bill or with one wing. The incubation period for the species is between 15 and 18 days, during which time the male feeds the female. Incubation begins as soon as the first egg is laid, so the chicks are born asynchronously. The chicks hatch with a covering of downy feathers. By around day three to five, feather quills emerge which will become the adult feathers. The chicks are brooded by the female for between 9 to 14 days. The female later joins the male in the task of bringing food. The young fledge in 26 to 29 days and remain with the parents for about a week more
Calls and Songs
The call is typically a trisyllabic oop-oop-oop, which gives rise to its English and scientific names, although two and four syllables are also common. In the Himalayas, the calls can be confused with that of the Himalayan cuckoo (Cuculus saturatus), although the cuckoo typically produces four notes. Other calls include rasping croaks, when alarmed, and hisses. Females produce a wheezy note during courtship feeding by the male. Both genders, when disturbed, call a rough charrrrrr, strongly reminiscent of the warning cry of the Eurasian jay. The food begging call of the nestlings is similar to that of a common swift: tiiii.