Contents:
It has four toes on each foot of which two are in rear and two in front; the nails are much curved long and remarkably keen or sharply pointed. It feeds on bugs worms and a variety of insects. From Wilson's American OrnithologyI 1. L ewis carried the specimens home and gave one to Charles Willson Peale for his museum in Philadelphia. There it was studied by the pioneer American ornithologist, Alexander Wilson , who made a drawing from it, and gave the bird its common name and its first scientific name, Picus torquatus PIE-kus tor-KWA-tus , Latin for "woodpecker with a necklace.
T o look at this bird is to open a window in time: The scene remains as elemental as ever, an earth-bound human, a sky-free bird, yet much has changed. Lewis's examination of the "black woodpecker" reveals the temperament of discovery he embodied for his time.
His description rings with a sensual curiosity toward nature, disciplined by an undistilled impulse to classify and measure.
His was a science of the five senses, grounded in the confidence that every natural mystery could be solved. Back in the mystery of here and now, it's early morning. Moisture tips tall grass; sunlight inches down a ruddy ponderosa pine tree; Lewis's woodpecker glides through latticed light.
It snatches an insect in midair, pirouettes, carries it back to a snag whose shattered crown is split by the morning shadow line, and disappears into a two-inch hole. In a nest hollowed from half-rotted wood, a foot or more inside the tree, young woodpeckers await their breakfast. In semidarkness they feed and grow.
Perhaps tomorrow a first flight, a first glimpse of full sun. But today the woodpecker reappears alone and wings away. Did it see me? Did its ancestors, so many bird generations ago, see Lewis? A number of species are adapted to spending a portion of their time feeding on the ground, and a very small minority have abandoned trees entirely and nest in holes in the ground.
The ground woodpecker is one such species, inhabiting the rocky and grassy hills of South Africa , [16] and the Andean flicker is another. The Swiss Ornithological Institute has set up a monitoring program to record breeding populations of woodland birds. This has shown that deadwood is an important habitat requirement for the black woodpecker , great spotted woodpecker , middle spotted woodpecker , lesser spotted woodpecker , European green woodpecker and Eurasian three-toed woodpecker.
Populations of all these species increased by varying amounts in the period to During this period, the amount of deadwood in the forest increased and the range of the white-backed woodpecker enlarged as it extended eastwards. With the exception of the green and middle spotted woodpeckers , the increase in the amount of deadwood is likely to be the major factor explaining the population increase of these species.
The majority of woodpeckers live solitary lives, but the spectrum of behaviour ranges from highly antisocial species that are aggressive towards their own kind, to species that live in groups. Solitary species will defend such feeding resources as a termite colony or fruit laden tree, driving away other conspecifics and returning frequently until the resource is exhausted. Aggressive behaviours include bill-pointing and jabbing, head shaking, wing flicking, chasing, drumming and vocalisations. Ritual actions do not usually result in contact and birds may "freeze" for a while before they resume their dispute.
The Discovery of Woodpecker Pithecus - Kindle edition by Norman L. Kincaide. Download it once and read it on your Kindle device, PC, phones or tablets. Long ago, even before Louis Leaky's famous find in Olduvai Gorge, there was a discovery, long suppressed by the scientific community, because of the.
The coloured patches may be flouted, and in some instances, these antagonistic behaviours resemble courtship rituals. Group-living species tend to be communal group breeders. Joining these flocks allows woodpeckers to decrease their anti-predator vigilance and increase their feeding rate. In many species the roost will become the nest-site during the breeding season, but in some species they have separate functions; the grey-and-buff woodpecker makes several shallow holes for roosting which are quite distinct from its nesting site.
Most birds roost alone and will oust intruders from their chosen site, but the Magellanic woodpecker and acorn woodpecker are cooperative roosters. Drumming is a form of non-vocal communication used by most species of woodpecker and involves the bill being repeatedly struck on a hard surface with great rapidity. After a pause, the drum roll is repeated, each species having a pattern which is unique in the number of beats in the roll, the length of the roll, the length of the gap between rolls and the cadence.
The drumming is mainly a territorial call, equivalent to the song of a passerine , with male birds drumming more frequently than females. Individual birds are thought to be able to distinguish the drumming of their mates and that of their neighbours. Woodpeckers do not have such a wide range of songs and calls as do passerine birds, and the sounds they make tend to be simpler in structure. Calls produced include brief high-pitched notes, trills, rattles, twittering, whistling, chattering, nasal churrs, screams and wails.
These calls are used by both sexes in communication and are related to the circumstances of the occasion; these include courtship, territorial disputes and alarm calls. Each species has its own range of calls, which tend to be in the 1 to 2.
Mated couples may exchange muted, low-pitched calls, and nestlings often issue noisy begging-calls from inside their nest cavity. The majority of woodpecker species live up to their name and feed on insects and other invertebrates living under bark and in wood, but overall the family is characterized by its dietary flexibility, with many species being both highly omnivorous and opportunistic. The diet includes ants, termites, beetles and their larvae, caterpillars, spiders, other arthropods, bird eggs, nestlings, small rodents, lizards, fruit, nuts and sap.
Many insects and their grubs are taken from living and dead trees by excavation. The bird may hear sounds from inside the timber indicating where it will be productive to create a hole. Other means are also used to garner prey. Some species such as the red-naped sapsucker sally into the air to catch flying insects, and many species probe into crevices and under bark, or glean prey from leaves and twigs.
The rufous woodpecker specialises in attacking the nests of arboreal ants and the buff-spotted woodpecker feeds on and nests in termite mounds. Other species such as the wrynecks and the Andean flicker feed wholly or partly on the ground. Ecologically, woodpeckers help to keep trees healthy by keeping them from suffering mass infestations. The family is noted for its ability to acquire wood-boring grubs from the trunks and branches, whether the timber is alive or dead.
Having hammered a hole into the wood, the prey is extracted by use of a long, barbed tongue. Woodpeckers consume beetles that burrow into trees, removing as many as 85 percent of emerald ash borer larvae from individual ash trees. The ability to excavate allows woodpeckers to obtain tree sap , an important source of food for some species. Most famously, the sapsuckers genus Sphyrapicus feed in this fashion, but the technique is not restricted to these, and others such as the acorn woodpecker and white-headed woodpecker also feed on sap. It was once thought that the technique was restricted to the New World , but Old World species, such as the Arabian woodpecker and great spotted woodpecker, also feed in this way.
All members of the family Picidae nest in cavities, nearly always in the trunks and branches of trees, well away from the foliage. Where possible, an area of rotten wood surrounded by sound timber is used. Where trees are in short supply, the gilded flicker and ladder-backed woodpecker excavate holes in cactus and the Andean flicker and ground woodpecker dig holes in earth banks. The campo flicker sometimes chooses termite mounds, the rufous woodpecker prefers to use ants nests in trees and the bamboo woodpecker specialises in bamboos.
Woodpeckers and piculets will excavate their own nests, but wrynecks will not, and need to find pre-existing cavities. A typical nest has a round entrance hole that just fits the bird, leading to an enlarged vertical chamber below. No nesting material is used, apart from some wood chips produced during the excavation; other wood chips are liberally scattered on the ground providing visual evidence of the site of the nest.
It takes around a month to finish the job and abandoned holes are used by other birds and mammals that are cavity nesters unable to excavate their own holes. Cavities are in great demand for nesting by other cavity nesters, so woodpeckers face competition for the nesting sites they excavate from the moment the hole becomes usable. This may come from other species of woodpecker, or other cavity nesting birds like swallows and starlings. Woodpeckers may aggressively harass potential competitors, and also use other strategies to reduce the chance of being usurped from their nesting site; for example the red-crowned woodpecker digs its nest in the underside of a small branch, which reduces the chance that a larger species will take it over and expand it.
Members of Picidae are typically monogamous , with a few species breeding cooperatively and some polygamy reported in a few species. Birds may be forced to remain in groups due to a lack of habitat to disperse to. A pair will work together to help build the nest, incubate the eggs and raise their altricial young. However, in most species the male does most of the nest excavation and takes the night shift while incubating the eggs. A clutch will usually consist of two to five round white eggs.
Since these birds are cavity nesters, their eggs do not need to be camouflaged and the white color helps the parents to see them in dim light. The eggs are incubated for about 11—14 days before they hatch. It then takes about 18—30 days before the chicks are fully fledged and ready to leave the nest. In most species, soon after this the young are left to fend for themselves, exceptions being the various social species, and the Hispaniolan woodpecker , where adults continue to feed their young for several months.
In general, cavity nesting is a successful strategy and a higher proportion of young are reared than is the case with birds that nest in the open. In Africa, several species of honeyguide are brood parasites of woodpeckers. The Picidae are just one of eight living families in the order Piciformes. Other members of this group, such as the jacamars , puffbirds , barbets , toucans , and honeyguides , have traditionally been thought to be closely related to the woodpecker family true woodpeckers , piculets , wrynecks and sapsuckers.
The clade Pici woodpeckers, barbets, toucans, and honeyguides is well supported and shares a zygodactyl foot with the Galbuli puffbirds and jacamars. The family Picidae was introduced by the English zoologist William Elford Leach in a guide to the contents of the British Museum published in Genetic analysis supports the monophyly of Picidae, which seems to have originated in the Old World , but the geographic origins of the Picinae is unclear. The Picumninae is returned as paraphyletic.
The evolutionary history of this group is not well documented, but the known fossils allow some preliminary conclusions: By that time, however, the group was already present in the Americas and Europe, and it is hypothesized that they actually evolved much earlier, maybe as early as the Early Eocene 50 mya. The modern subfamilies appear to be rather young by comparison; until the mid- Miocene 10—15 mya , all picids seem to have been small or mid-sized birds similar to a mixture between a piculet and a wryneck. On the other hand, there exists a feather enclosed in fossil amber from the Dominican Republic , dated to about 25 mya, which seems to indicate that the Nesoctitinae were already a distinct lineage by then.
Stepwise adaptations for drilling, tapping and climbing head first on vertical surfaces have been suggested. The first adaptations for drilling including reinforced rhamphotheca , frontal overhang and processus dorsalis pterygoidei evolved in the ancestral lineage of piculets and true woodpeckers.
Additional adaptations for drilling and tapping enlarged condylus lateralis of the quadrate and fused lower mandible have evolved in the ancestral lineage of true woodpeckers Hemicircus excepting. The inner rectrix pairs became stiffened, and the pygostyle lamina was enlarged in the ancestral lineage of true woodpeckers Hemicircus included , which facilitated climbing head first up tree limbs. Genus Hemicircus excepting, the tail feathers were further transformed for specialized support, the pygostyle disc became greatly enlarged, and the ectropodactyl toe arrangement evolved.
These latter characters may have facilitated enormous increases in body size in some lineages. Prehistoric representatives of the extant Picidae genera are treated in the genus articles.
An enigmatic form based on a coracoid found in Pliocene deposits of New Providence in the Bahamas , has been described as Bathoceleus hyphalus and probably also is a woodpecker. The phylogeny of woodpeckers is still being refined and the positions of some genera continue to be unclear and there are conflicting findings from analyses as of In general, humans consider woodpeckers in a favourable light; they are viewed as interesting birds and fascinating to watch as they drum or forage.
However, their activities are not universally appreciated. Such activity is very difficult to discourage and can be costly to repair. Woodpeckers also drum on various reverberatory structures on buildings such as gutters, downspouts, chimneys, vents and aluminium sheeting. Several exploratory holes may be made, especially at the junctions of vertical boards or at the corners of tongue-and-groove boarding.
The birds may also drill holes in houses as they forage for insect larvae and pupae hidden behind the woodwork. Woodpeckers sometimes cause problems when they raid fruit crops, but their foraging activities are mostly beneficial as they control forest insect pests such as the woodboring beetles that create galleries behind the bark and can kill trees. They also eat ants, which may be tending sap-sucking pests such as mealybugs , as is the case with the rufous woodpecker in coffee plantations in India. Their hole-making abilities make their presence in an area an important part of the ecosystem, because these cavities are used for breeding and roosting by many bird species that are unable to excavate their own holes, as well as being used by various mammals and invertebrates.
The spongy bones of the woodpecker's skull and the flexibility of its beak, both of which provide protection for the brain when drumming, have provided inspiration to engineers; a black box needs to survive intact when a plane falls from the sky, and modelling the black box with regard to a woodpecker's anatomy has increased the resistance of this device to damage sixty-fold. One of the accounts of the Founding of Rome , preserved in the work known as Origo Gentis Romanae , refers to a legend of a woodpecker bringing food to the boys Romulus and Remus during the time they were abandoned in the wild - thus enabling them to survive and play their part in history.
In a global survey of the risk of extinction faced by the various bird families, woodpeckers were the only bird family to have significantly fewer species at risk than would be expected. Being woodland birds, deforestation and clearance of land for agriculture and other purposes can reduce populations dramatically. Some species adapt to living in plantations and secondary growth, or to open countryside with forest remnants and scattered trees, but some do not.
A few species have even flourished when they have adapted to man-made habitats. There are few conservation projects directed primarily at woodpeckers, but they benefit whenever their habitat is conserved.