Woodpeckers - Knock Knock, who's There?

As their names suggests, woodpeckers are birds which specialise in pecking into wood. This they do to extract food (most species are insectivorous) and also to excavate nesting chambers. There are 221 recognised species in 28 genera and they occur throughout the world except in Australasia. Although all members of the family confirm to a rather standard body shape, there is considerable variation in size with the tiny piculets measuring less that 10cm and the huge Imperial Woodpecker (sadly thought to be extinct) up to 60cm. Southeast Asia's Great Slaty Woodpecker measures 50cm from the tip of its pointed bill to its hooked toes. In temperate regions and in Africa, woodpeckers are rather drably coloured, with olive green, brown and black being dominant colours; although males typically have vivid scarlet crests or malar stripes. In tropical America and Asia, woodpeckers are much more glamorous with brilliant yellows, greens, and reds commonplace.

Anatomical Features

Woodpeckers have several unique anatomical features which allow them to live the way they do. Most remarkable, is the long tongue which is extended into holes made in the trunks and branches of trees. This muscular tongue may be almost as long as the bird itself and encircle the eye orbit and nostril when retracted. The tongues of ant-feeding woodpeckers are generally longer and coated with sticky saliva, while other woodpeckers have barb-tipped tongues for spearing beetle larvae hidden in dry timber. The so-called sapsuckers of North and Central America feed on sweet sap which pours from holes they bore into trees. Other woodpecker adaptations include skull modifications which reduce compression caused when the bird strikes hard wood; powerful neck muscles; toes arranged to enable gripping on vertical trunks; and stiffened tail feathers which serve to brace the bird when it is hammering for food or tunnelling.

Diversity

There are 23 woodpecker species in Africa. The Bearded, Golden-tailed, Nubian, Bennett's and Cardinal are familiar birds of open woodland and savanna, while the Olive and Knysna woodpeckers are at home in temperate forests. The large Ground Woodpecker is confined to the mountains of the Drakensberg and the southern Cape. The tiny African Piculet is found in tropical rainforest from West Africa to Uganda.
The related Red-throated Wryneck is found in open wooded grassland and is particularly common on the Highveld around Johannesburg.

Breeding

Woodpeckers are strongly territorial and call regularly throughout the day, and throughout the year, to defend their breeding (or feeding) range. Many of the larger species, such as the Bearded Woodpecker knock their bills against wood at high speed to create a loud drumming sound which may carry for several kilometres. The Nubian Woodpecker is a raucous and seemingly sociable species which goes about in noisy family groups which may breed co-operatively. All woodpeckers lay white eggs in cavities which they have created themselves; although the majority nest in tree trunks, others bore into termite nests or earthen banks.

CC Africa's Woodpecker Hotspots

A variety of woodpecker species can be seen at virtually all CC Africa properties. Many are quite inconspicuous but patient birdwatchers are often rewarded. The Knysna Woodpecker (endemic to south Africa) may be seen in riverine scrub at Kwandwe, while the ground-feeding Bennett's Woodpecker is common at Matetsi, Sandibe, Nxabega and Ngala. In the Serengeti, the Grey Woodpecker and Nubian are the most conspicuous species and are regularly encountered in the vicinity of Grumeti and Klein's Camp.

-Duncan Butchart -

Posted: Birds by CC Africa, Date: 21 November 2006