Shrikes (Laniidae)

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Shrikes

(Laniidae)

Class Aves

Order Passeriformes

Suborder Passeri (Oscines)

Family Laniidae


Thumbnail description
Small to relatively large birds with a more or less sharply hooked bill and strong legs; feet and claws adapted for catching prey

Size
5.7–19.6 in (14.5–50 cm); 0.63–3.52 oz (18–100 g)

Number of genera, species
12 genera; 74 species

Habitat
Forest, woodlands, savannas, cultivated areas

Conservation status
Critically Endangered: 2 species; Endangered: 5 species; Vulnerable: 2 species; Near Threatened: 5 species

Distribution
Africa, Europe, Russia, Asia, Indonesia, New Guinea, North America

Evolution and systematics

The origin of shrikes is not known for certain. A fossil of a shrike-like bird (Lanius miocaenus) found in Lower Miocene deposits in France, indicates that the genus Lanius existed in Europe 25–30 million years ago. African origins have been suggested by various authors who consider that, out of the 74 species classically retained in the shrike family, only 10 have no link with Africa. These birds all belong to the genus Lanius, which still has nine endemic species on the African continent and may well have invaded Eurasia, where it also radiated.

The theory of African shrike origins, however, has recently been questioned, as molecular studies suggest that shrike ancestors originated in the Australasian region. From there, as Australia drifted northwards some 20–30 million years ago in the Tertiary period, shrikes might have emigrated to Asia.

Shrikes probably arrived much later in North America, where the loggerhead shrike (L. ludovicianus) may represent a first wave of shrike immigrants to the New World. L. ludovicianus may have been pushed south by a glacial epoch and was later followed by another wave of birds in the northern parts of the continent. It may be these birds that are now regarded as a race of the northern shrike (L. excubitor), which has a large holarctic distribution. The more common and widespread west-palearctic red-backed shrike (L. collurio) may be a much more recent invader, or re-invader, of northern latitudes after the retreat of the last glaciers about 12,000 years ago. Its typical migration pattern may reflect the route of its progressive northward spread. Its resident ancestor in Africa could be the very similar Emin's shrike (L. gubernator), known today from a belt spreading from central-west Africa to central-east Africa.

The most widely accepted standard sequence for recent birds dates back to the 1960s. It recognizes four subfamilies in the Laniidae, with 74 species in all. The subfamilies and the genera concerned are the following:

  • Prionopinae (helmet-shrikes): Eurocephalus (two species); Prionops (seven species)
  • Malaconotinae (bush-shrikes): Lanioturdus and Nilaus (monotypic); Dryoscopus (six species); Tchagra (six species); Laniarius (10 species); Telophorus (10 species); Malaconotus (five species)
  • Laniinae ("true" shrikes): Corvinella (two species); Lanius (23 species)
  • Pityriasinae (Bornean bristlehead): Pityriasis (one species)

Recent studies of genetic material and behavior, as well as observations of morphological and plumage characteristics, however, suggest that the above classifications may not reflect the true relationships among shrikes. Lefranc (1997) and Harris (2000) have suggested alternate taxonomies.

Physical characteristics

Bush-shrikes are a mixed group with at least seven genera. Malaconotus bush-shrikes are large birds (9.1–9.8 in [23–25 cm]) with a strong bill and beautiful, bright colors. Their upper-parts are mainly olive-green and their underparts may be green or, more often, yellow with red or orange. A marked polymorphism occurs in the fiery-breasted bush-shrike (M. cruentus). Some species of the genus Telophorus are very similar,

but are smaller and have a weaker bills. The many-colored bush-shrike (T. multicolor) shows yellow, orange, red, buff, and even black morphs; the very rare Mount Kupé bush-shrike (T. kupeensis) measures about 8.7 in (22 cm), is mainly gray with a distinct black face-mask, a white throat, and a yellow vent. The birds of the genus Laniarius are robust, medium to large (6.7–9.8 in [17–25 cm]), with black or mainly black upper-parts; their underparts may be black, white, red, orange, or yellow. Dryoscopus species are somewhat similar, often with a pied coloration; contrary to all the species mentioned above, they show a more or less strong sexual dimorphism. Their English name, puffback, is due to the fact that they can erect the thick, fluffy feathers of their back and rump into a puff. Tchagras are medium to large in size (6.3–9.1 in [16–23 cm]) with gray or gray-brown upper-parts, chestnut wings, black-streaked head, and a rather long, graduated tail; the sexes are similar, except in the marsh tchagra (Tchagra minuta), which is sometimes placed in its own genus. The brubru (Nilaus afer) is small (about 5.5 in [14 cm]) with a pied plumage; its white eyebrow is characteristic, and most races show rufous flanks. The strange white-tailed shrike (Lanioturdus torquatus) (5.9 in [15 cm]) is also pied with long legs and a very short, white tail.

Helmet shrikes (Prionops) are small to relatively large (7.5–9.8 in [19–25 cm]) with a fairly stout bill. Their plumage is generally contrasted, and white, black, and gray are often the dominant colors. The bill is most often white, but can be red in some species. The group is characterized by the presence of stiff, bristle-like feathers on the forehead and, in most species, by a colored wattle around the eye. The two very similar Eurocephalus species are plump and relatively large (7.5–9.8 in [19–25 cm]); their plumage is pied and buffy, and their snow-white crown has given them their English name of white-crowned shrikes.

In the true shrikes, the two Corvinella species are large and long-tailed. The yellow-billed shrike (C. corvina) (12 in [30 cm] including tail, or 7 in [18 cm]) has a brown, vermiculated plumage and resembles a giant, juvenile Lanius shrike. The magpie-shrike (C. melanoleuca) (18 in [45 cm] including tail, or about 12 in [30 cm]) is almost completely black with white scapulars and wing patches. Lanius shrikes are small to relatively large birds (5.9–11.8 in [15–30 cm]). The smallest is the central African Emin's shrike; the largest is the high-elevation race giganteus of the Chinese gray shrike (L. sphenocercus). All Lanius bear the "highwayman's mask," which can extend well over the bill. The most common colors in the plumages are black, white, and various shades of gray and brown; however, deep chestnut, yellow, or even orange, can occur. One of the most brightly colored Lanius is the race tricolor of the Asian long-tailed shrike (L. schach). Males and females are often quite similar; sexual dimorphism is only very obvious in a few species and particularly in the red-backed shrike. Young birds are typically brown and heavily vermiculated.

Distribution

Almost all the bush-shrikes are found in Africa, south of the Sahara. The only exception is the black-crowned tchagra (Tchagra senegala), which is widespread on the African continent and has two isolated races, one in north Africa and the other on the southwest Arabian peninsula, in Yemen and Oman. Among the most widespread species are the gray-headed bush-shrike (Malaconotus blanchoti) and its smaller replica, the orange-breasted bush-shrike (Telophorus sulfureopectus); the two species have almost the same vast breeding range in sub-Saharan Africa. Among the very rare species are the Mount Kupé bush shrike, known only from two or three tiny areas in Cameroon, and the Bulo Berti boubou, known from only one individual in central Somalia.

Helmet-shrikes are confined to sub-Saharan Africa. The most widespread species found in west, east, and southern Africa is the white-crested helmet-shrike (Prionops plumata).

True shrikes are also well represented in sub-Saharan Africa. The genus Corvinella occurs only there, but the most widespread species is the common fiscal (Lanius collaris); with about 10 races, it can be seen almost everywhere in adequate habitats. The rarest species is the rather similar Sao Tomé fiscal (L. newtoni), confined to an island in the gulf of Guinea. Two Lanius species breed both in north Africa and Eurasia: the southern gray shrike (L. meridionalis) and the woodchat (L. senator). Populations of the latter also migrate from Eurasia to Africa, as populations of three other Lanius do. Other shrikes of the same genus are common in Asia; a race of the long-tailed shrike breeds in New Guinea. Only two species have reached North America: the holarctic northern shrike, which has some breeding populations beyond the Arctic circle and breeds in Alaska and northern Canada, and the very similar endemic loggerhead shrike (L. ludovicianus).

Habitat

The large bush-shrikes of the genus Malaconotus and the generally smaller species of the genus Telophorus are birds of the forest, occurring in lowland and montane woodland up to 9,800 ft (3,000 m); they are arboreal, often skulking in canopies and sometimes in undergrowth. The puffbacks (Dryoscopus) most often inhabit canopies of forest or other habitats rich in high trees, including suburban gardens. Gonoleks and boubous (Laniarius) occur in all kinds of thickets and dense shrub; they generally live rather low in the vegetation and spend much of the time foraging on the ground. The tchagras are more terrestrial and inhabit a variety of semi-open habitats, generally arid and dominated by dense shrub; the marsh tchagra, however, lives in humid areas dominated by reeds or papyrus. The white-tailed shrike is also a terrestrial bird, typically found in the semi-arid scrub savanna extending from Namibia to southwestern Angola.

Helmet shrikes are found in a wide range of open wooded savannas or woodlands. Highly gregarious groups fly from one tree to another in the search of insects. The most common species, the white-crested helmet shrike, may occur in suburban gardens outside the breeding season.

True shrikes are typical birds of semi-open habitats; they need perches of some kind with a good view on the ground, where most of their prey is taken. Most species have benefited from deforestation and have adapted well to low intensity types of farming. A few species are forest birds, however. The rarest, the São Tomé fiscal, is restricted to primary low-land

and mid-altitude forest; it has never been recorded in secondary forest or in cultivated areas.

Behavior

Bush-shrikes are generally seen singly or in pairs, but small parties, probably family groups, have been recorded. They appear to be monogamous and territorial, but very little is known about the social organization of many species, as their tendency to keep to thick cover makes them difficult to observe. One of the easiest to spot is the beautiful, long-tailed, rosy-patched shrike (Tchagra cruentus), which lives in dry bush areas in eastern Africa. Its noisy family groups are constantly active, flying low or hopping on the ground. Members of a pair may be conspicuous in breeding time, when they project their melodious whistles from the top of a bush. Song is an important means of communication in tropical forests or dense shrub and often betrays the presence of bush-shrikes. Malaconotus species project many sounds, including distinctive, far-carrying whistles and bell-like phrases. Laniarius are well-known for their extraordinary duet-songs; what appears to be the call of a single bird is often a kind of whistle by the male immediately followed by generally harsher notes by the female. The brubru bears its name well; its call is onomatopoeic and recalls the trilling song of the male. Some tchagras produce clear lilting, melodious, almost human-sounding

phrases that may accompany typical display flights. These displays start with a steep climb, during which the wings are extended and the tail is fanned out, and they end with a gliding descent. The puffbacks may be seen for a few seconds during their short butterfly flights, made with their puff expanded. Most bush-shrikes are apparently sedentary, although local movements are obvious in a few species. Altitudinal movements have been recorded in the olive bush-shrike (Telophorus olivaceus) in Malawi and Zimbabwe.

Helmet-shrikes are easier to observe; they are highly sociable with up to 30 birds in a single group; they forage and roost communally and breed cooperatively, with each group under the dominance of the only breeding female. Most species have local or altitudinal movements.

Two African true shrikes are gregarious: the long-tailed fiscal (L. cabanisi) and the gray-backed fiscal (L. excubitoroides). The latter, and possibly also the former, breed cooperatively, with only one breeding pair that benefits from the presence of a varying number of helpers. All the other species are found singly or in solitary pairs. However, loose colonies are known, particularly in the case of the lesser gray shrike (L. minor), and concentrations may also occur during migration. All Lanius are normally monogamous; that, however, does not exclude extra pair paternity, which has been proven in at least three species. They are also highly territorial, with territories covering on average 3.7 acres (1.5 ha) in the small red-backed shrike and up to 250 acres (100 ha) or more in the much larger northern shrike. In many Lanius species, songs are relatively rare and not far-carrying, although territorial calls are important. Almost all or all Lanius shrikes impale their prey, but the regularity of this behavior varies between and even within species. Pair formation takes place inside the territory, displayflights are known in some species, and curious group meetings have been recorded in the northern shrike and in the loggerhead shrike. Courtship feeding is regular. Depending on latitude and feeding habits, Lanius species can be resident; or partial, altitudinal, or long-distance migrants. African species are probably sedentary, while some populations of the Eurasian red-backed and lesser gray shrikes may travel 6,200 mi (10,000 km) or more.

Feeding ecology and diet

All types of shrikes feed on a large variety of arthropods and are largely insectivorous. Small vertebrates and birds' eggs are also on the menu for the larger Malaconotus species and the true shrikes. At least some of the true shrikes occasionally indulge in small fruits and berries.

Bush-shrikes most often feed by gleaning the vegetation inside branches, trunks, and foliage, and have been compared to oversized warblers. Prey is taken at various forest levels according to the species. Some, like the rare Uluguru bush-shrike (Malaconotus alius), appear to be confined to the canopy; while others, like the gray-headed bush-shrike, forage at all levels. Where two related species come into contact, there might be an ecological segregation, and each shrike keeps to its preferred level. Some species, like the tchagras, some boubous, gonoleks, and the white-tailed shrike, pick much of their captures off the ground, where they hop about in the vegetation.

Helmet-shrikes search for food in noisy, sometimes mixed, groups. They may forage from ground to canopy, but seem to prefer middle or lower levels; at least some Prionops, when perched on a branch and looking for prey, tilt their heads on one side as if they were listening to their future victims.

True shrikes are "sit and wait" predators that spend a lot of time on a variety of perches. Prey is mainly caught on the ground, but in fair weather a lot of insects are hawked in the air. Impaling or wedging of prey is regular in Lanius, but has not been recorded in all species. It is regular in larger species like the northern shrike, which must anchor its small vertebrate victims in order to dismember and eat them. Impaled prey can serve as a larder available in bad weather, when insects are not very active. The habit of impaling for a few days may enable species like the loggerhead shrike to consume toxic prey once it has degraded. Impaling may also serve as mate attraction. The more prey that is impaled in a territory, the better the male may appear to a female, but this point needs further research. Impaling or wedging is not entirely confined to Lanius; it is regularly recorded in the gray-headed bush-shrike and may occur in other Malaconotus; it has occasionally been recorded in Laniarius, but so far only in captivity.

Reproductive biology

All bush-shrikes appear to be monogamous and territorial. The most remarkable aspects of courtship behavior are dueting, mainly found in Laniarius; the "puffback" displays of Dryoscopus; and the flight songs of Tchagra. Courtship feeding is known in the gray-headed bush-shrike; it may occur in the brubru. Nests, built in trees or bushes, are tidy cups made up of fine rootlets, twigs, and grass. Some species like to incorporate spider web, but the medal of originality goes to the marsh tchagra, which often decorates its nest with snake skin. A few nests, like those built by the rosy-patched shrike, are flimsy, almost transparent, and recall those of doves. Bush-shrikes lay few eggs, most often only two or three. The breeding season appears to be favored by the start of a rainy season.

Helmet-shrikes are cooperative breeders, with a dominant breeding pair assisted by helpers. The nest is a compact cup, generally built on a horizontal branch, often made of bark and decorated with spider web. Prionops lay two to five eggs, often four. The breeding biology of five of seven Prionops helmet-shrike species remains virtually unknown.

Cooperative breeding also occurs in true shrikes, in the two species of Corvinella, and in at least one species of African Lanius, the gray-backed fiscal. Lanius nests are of the classical cup-shaped type, generally well structured, but not always neatly made. Eggs number between three and eight; clutch-size varies with latitude, both within the genus and within populations of the same species. The African Lanius lay generally few eggs, for instance, apparently never more than three in Sousa's shrike (L. souzae). However, in Alaska the modal clutch-size of the northern shrike is eight eggs. Young Lanius stay in the nest for two to three weeks, depending on the species, weather conditions, and availability of food.

Conservation status

Nine species of shrikes have the unhappy privilege of being on the list of the globally threatened species, including six bush-shrikes, two helmet-shrikes, and one true shrike. They all live in sub-Saharan Africa, where they are still poorly known and have a very small range. Another common characteristic is that they almost all, including the Lanius shrike, live in forest habitats. The possible exception is the recently discovered Bulo Berti boubou; the only known individual was trapped in acacia shrub. All these birds have habitats that face deforestation for the benefit of various types of agriculture.

Population estimates must be taken with extreme caution. It is assumed that the Bulo Berti boubou population totals fewer than 50 pairs in the only area where it is known in Somalia. The Gabela bush-shrike (Laniarius amboimensis) and the orange-breasted bush-shrike (L. brauni) both live in tiny areas in western Angola and have populations that are thought to be between 250 and 1,000 pairs. The Mt. Kupé bush-shrike and the green-breasted bush-shrike (Malaconotus gladiator) are mainly confined to western Cameroon; the latter species also has a tiny population in eastern Nigeria. They are respectively thought to have populations numbering between 50 and 250 pairs and between 2,500 and 10,000 pairs. The population of the Uluguru bush-shrike (Malaconotus alius), endemic to the mountains of the same name in eastern Tanzania, benefited from a detailed survey in 2000. The results were rather encouraging, as about 1,200 pairs were located, thus doubling previous estimates. The two helmet-shrikes on the Red List are the Endangered Gabela helmet-shrike (Prionops gabela) with 1,000–2,500 pairs in western Angola, and the Vulnerable yellow-crested helmet-shrike (Prionops alberti) with 2,500– 10,000 pairs in the east of the Democratic Republic of Congo. The São Tomé fiscal is endemic to the island of the same name, which lies in the gulf of Guinea, 160 mi (255 km) off the coast of Gabon. It is the only true shrike on the IUCN

Red List. It is judged to be Critically Endangered with perhaps fewer than 50 pairs; other estimates, however, give a few hundred pairs.

Another five species are classified as Near Threatened. Three are in Africa: two bush-shrikes and one helmet-shrike; two are in Asia: one Lanius shrike and the Bornean bristle-head.

Almost all the species mentioned above are confronted with a major problem: deforestation. That is, however, not the general cause explaining the present worrying decline of Lanius shrikes in North America and Europe; on the contrary, these semi-open habitat species have certainly benefited from the clearance of forests. They have adapted extremely well to "untidy" open landscapes associated with low-intensity farming. A strong association exists between them and the lifestyle based around cultivation and domestic stock. The golden age for many such shrikes has, however, come to an end with the industrialization of agriculture. Large-scale production techniques have involved a high level of mechanization and an increase in field size. This has led to the disappearance of large areas of non-productive habitats, such as hedgerows, bushes, isolated trees, ponds, marshes, banks, ditches and even of grassy paths, which are favored by shrikes. Widespread use of pesticides has reduced their food resources.

Significance to humans

True shrikes are miniature birds of prey and were generally regarded as harmful up to about the middle of the twentieth century, both in Europe and in North America. This negative reputation was reflected in the writings of hunters and gamekeepers, but also in those of some ornithologists. Shrikes are still hunted by humans in many parts of the world, particularly when they migrate. Many are killed in the Middle East and Greece. In Turkey, numerous red-backed shrikes are caught, blindfolded, and used as decoys to attract and net sparrowhawks (Accipiter nisus); the raptors are then trained and used to catch common quail (Coturnix coturnix). In Taiwan, the brown shrike (Lanius cristatus) is caught with bamboo foot traps, killed, sold, and barbecued for tourists visiting a national park.

In the western world, shrikes have gained a better reputation; but the birds are confronted with drastic habitat changes. The decline of shrikes, their beauty, and the fact that they are generally conspicuous and easy to study, has prompted the creation of an International Shrike Working Group. It met for the first time in Florida in 1991 and organizes regular meetings that are followed by the publication of proceedings. So far it has only taken a strong interest in true shrikes, but the other shrike-like birds should not be forgotten. Very little is known about them, but it is obvious that a few species are already endangered. Much of their future will depend on the development of ornithology and conservation measures in Africa.

Species accounts

List of Species

White helmet-shrike
Northern puffback
Black-crowned tchagra
Yellow-crowned gonolek
Gray-headed bush-shrike
Red-backed shrike
Long-tailed shrike
Loggerhead shrike

White helmet-shrike

Prionops plumatus

subfamily

Prionopinae

taxonomy

Prionops plumata Shaw, 1809, Senegal. Up to nine races described. Variation affects size, amount of white in wings, and characteristics of frontal feathers and crest.

other common names

English: White-crested helmet-shrike, curly-crested helmet-shrike; French: Bagadais casqué German: Brillenwürger; Spanish: Alcaudón de Copete Yelcobé.

physical characteristics

7.4–9.8 in (19–25 cm); 0.88–1.3 oz (25–37 g). A relatively large species; sexes similar. Mainly black on upperparts, but with white wing-stripe; wholly white on underparts; head whitish with stiff frontal feathers and long, straight crest; eyes yellow surrounded by yellow wattle. In flight, obvious white patch in wings and white outer feathers in tail. Juveniles are similar, but duller, with no crest and no wattle. Race cristatus (Ethiopia) has no white in the wings and its long crest curls forward. Race talacoma (parts of eastern and southern Africa) shows a grayish head and has no long crest.

distribution

Most common and widespread helmet-shrike, exclusively in sub-Saharan Africa. Absent from some parts of south, central-western and eastern Africa.

habitat

Woodlands and wooded savannas, sometimes in suburban gardens outside breeding season. Occurs up to 5,900 ft (1,800 m) in Kenya.

behavior

Highly gregarious in all seasons. A given group generally numbers up to seven birds, but up to 22 have been recorded together outside the breeding season. The group defends a home range covering about 50 acres (20 ha) (10–75 acres [5–30 ha]). When searching food, birds fly from tree to tree and may be seen anywhere between ground and canopy. Local movements are known, but not yet fully understood; they appear to be favored by drought years.

feeding ecology and diet

All kinds of arthropods, mainly insects and particularly butterflies and moths, as well as their caterpillars. Small reptiles are sometimes taken.

reproductive biology

Monogamous cooperative breeder. Only one dominant pair breeds and is assisted by what are thought to be closely related birds. Over the vast breeding area, egg-laying may occur almost in any month. Lays two to five eggs, most often four, in a cup-shaped nest made of bark that is cemented and decorated with spider web. It is placed a few yards (meters) above the ground in a tree. Incubation done by all the birds, but probably mostly by the dominant pair, for about 18 days. Young stay in the nest about 20 days; they are still fed by the group when about two months old.

conservation status

Not threatened.

significance to humans

None known.


Northern puffback

Dryoscopus gambensis

subfamily

Malaconotinae

taxonomy

Lanius gambensis Lichtenstein, 1823, Senegambia. Taxonomy still unclear; up to five races described; variation relatively well marked, but only in color of underparts and upperparts of females. Appears to be very close both to Pringle's puffback (D. pringli), an uncommon resident in eastern Africa, and to the black-backed puffback (D. cubla), which is widespread south of the equator.

other common names

English: Gambian puffback-shrike; French: Cubla de Gambie; German: Gambia-Schneeballwürger; Spanish: Obispillo Común.

physical characteristics

7–7.5 in (18–19 cm); 0.95–1.37 oz (27–39 g). The red-eyed male has mainly glossy black upperparts, but scapulars, rump,

wing-coverts, and edges of wing-feathers are pale gray; underparts are creamy white. Female is duller with orange eyes, gray-brown upperparts, and mainly creamy reddish underparts; the intensity of these colors varies with races. Young birds are similar to the adult female, but have reddish tips on upperparts and brown eyes. In the eastern race erythrea, the female strongly resembles the male; her upperparts are, however, dark brown instead of black, and her underparts are generally creamier.

distribution

Most common puffback north of the equator; found in a broad belt stretching from Senegambia to Eritrea and Ethiopia; almost absent from the Horn. Nominate from Senegal to Cameroon; most distinct race, erythrea from eastern Sudan to northwestern Somalia.

habitat

All types of savanna woodland and areas with large trees, including gardens; avoids closed forests. In Eritrea occurs up to about 4,900 ft (1,500 m).

behavior

Generally solitary or occurring in pairs, keeping to the tree canopy. Only relatively easily spotted and seen for a few seconds in breeding season when very demonstrative. Males fly from tree to tree with back and rump feathers fluffed out. Thought to be sedentary, but local movements are possible.

feeding ecology and diet

Arthropods, mainly insects and particularly caterpillars gleaned from foliage.

reproductive biology

Territorial and probably monogamous. Little known. Few nests found; generally high up in trees; plastered with spider web. Appears to breed in any month of the year.

conservation status

Not threatened.

significance to humans

None known.


Black-crowned tchagra

Tchagra senegala

subfamily

Malaconotinae

taxonomy

Lanius senegala Linnaeus, 1776, Senegal. About 12 races described, but a few poorly differentiated. Variation concerns size, coloration of back and underparts, and coloration and shape of superciliary stripe.

other common names

French: Tchagra à tête noire; German: Senegaltschagra; Spanish: Chagra.

physical characteristics

7.8–9 in (20–23 cm); on average 1.9 oz (54 g). Relatively large with a long, graduated tail and a heavy black bill; sexes are similar. Characteristic black crown and black stripe through eye; white, prominent supercilium. In nominate, upperparts are gray brown; tail is dark fringed and tipped white; underparts are pale gray. Juveniles are similar to adult, but duller with a mottled crown, buff eyebrow, and paler bill. The Arabian race percivali is the darkest one, relatively similar to the North African race cucullata, also darker than nominate; on the contrary remigialis from Chad to Sudan is very pale with almost pure white underparts.

distribution

Rather a coastal species in northwestern Africa from Morocco to northern Libya (race cucullata). Nominate occurs from Senegambia to Sierra Leone. Other races widespread in sub-Saharan Africa, except in the Horn, the Congo basin, and the southwestern area of the continent.

habitat

Wide range of semi-open habitats dotted with bushes, thickets, and isolated trees; sometimes occurs in forested habitats, in Ethiopia, up to 9,800 ft (3,000 m); also in plantations, parks, and gardens.

behavior

The male defends a rather small territory covering about 10 acres (4 ha). Generally secretive; likes to keep to inside of bushes, but song of warbled whistles betrays its presence. Also conspicuous during display flights, when it can climb up to 50 ft (15 m) before gliding downward in full song toward another perch. Spends much of its time hopping on the ground where most prey is caught, particularly near bases of bushes and trees. Only local movements are known and only in a few areas.

feeding ecology and diet

Arthropods, mainly insects, particularly grasshoppers and beetles. Small reptiles and amphibians, as well as berries, are also taken.

reproductive biology

Monogamous, occurs singly or in pairs. The nest is a shallow cup, built in a bush or small tree generally between 1.6 and 6.5 ft (0.5 and 2 m) above the ground. A normal clutch contains two or three eggs (rarely four), which are apparently incubated by both sexes, but probably mainly by female, for about 14 days. Over the vast range, laying may begin in all months with local peaks, possibly favored by early rains. Normally only one clutch. Young leave the nest when they are about 16 days old.

conservation status

Not threatened. A few isolated races like percivali in the southwestern Arabian peninsula, might, however, deserve to attract the attention of conservationists.

significance to humans

None known.


Yellow-crowned gonolek

Laniarius barbarus

subfamily

Malaconotinae

taxonomy

Lanius barbarus Linnaeus, 1766, Senegal. Two races; slight differences mainly affecting coloration of crown and nape.

other common names

French: Gonolek de Barbarie; German: Goldscheitelwürger; Spanish: Gonolek Común.

physical characteristics

9.0–9.8 in (23–25 cm); on average 1.7 oz (49 g). A robust, relatively large, and brightly colored species. The similar sexes have black upperparts contrasting with a golden crown, brown

eyes, and vermilion red underparts. Juveniles are similar, but have duller upperparts and buffy underparts with heavy dark barring. Race helenae has a deeper reddish crown.

distribution

Western Africa from southern Mauritania to northern Cameroon. Helenae is confined to coastal areas in Cameroon.

habitat

Dense, woody undergrowth in savannas; the Sierra Leone race inhabits mangroves.

behavior

Occurs singly or in pairs. Spends much time in low vegetation and on the ground, but may also look for prey on small branches up to about 16 ft (5 m). Its flight is short and appears heavy. More often heard than seen; produces remarkable duets that sound as if they were produced by a single bird. Sedentary as far as known.

feeding ecology and diet

Arthropods, mainly insects and particularly caterpillars and grasshoppers. Said to predate on birds' nests.

reproductive biology

Monogamous and territorial. Few precise data available. The nest is hidden relatively low, between 4.9 and 14.8 ft (1.5–4.5m) in a dense bush or a small tree. It receives two, or more rarely three, eggs. Eggs may be laid at any time of the year.

conservation status

Not threatened. The precise status of the Sierra Leone race might require further investigations.

significance to humans

None known.


Gray-headed bush-shrike

Malaconotus blanchoti

subfamily

Malaconotinae

taxonomy

Malaconotus blanchoti Stephens, 1826, Senegal. Up to seven races described with regular intergradation at common boundaries. Main differences concern color of underparts.

other common names

French: Gladiateur de Blanchot; German: Graukopfwürger; Spanish: Gladiador de Cabeza Gris.

physical characteristics

9–10.2 in (23–26 cm) on average 2.7 oz (77 g). One of the largest is the Malaconotus shrike, which has a heavy bill. Sexes are similar. Head and nape is grayish; eyes are pale yellow and lores are white. Upperparts and wings are mainly olive green; wings show yellow spots to coverts. Underparts are yellow with a varying amount of orange on breast. Juveniles are similar, but duller and with brown eyes. Adult of nominate form, in West Africa, has no or little orange on its underparts, which are very dark in the eastern African race approximans. Race hypopyrrhus from Tanzania southwards has less intensively colored underparts.

distribution

Widespread in sub-Saharan Africa, but absent from the Horn, the Congo basin, and the southwestern area of the continent.

habitat

Various types of woodlands, including riverine woods; can also occur in large parks or suburban gardens.

behavior

Seen solitary, in pairs, or in family groups. Territory covers about 124 acres (50 ha) and is advertised by various sounds, particularly by mournful, far-carrying whistles. Generally elusive, it hides in dense thickets, but may be relatively conspicuous during courtship activities, which include a display flight. Looks for food at all levels of vegetation, also occasionally on ground. Remarkably, caches food like Lanius shrikes; small vertebrates can be wedged into forks. Local movements have been suspected; they might be related to the onset of rains.

feeding ecology and diet

Arthropods: scorpions, worms, centipedes, but mainly insects. Small birds and reptiles are also regularly taken.

reproductive biology

Monogamous, though little is known. The nest is an untidy cup, generally placed at about 13 ft (4 m) above the ground in a small, deciduous tree; it receives two to four, and most often three eggs. The laying season varies with the geographical area. Female alone appears to incubate for about 16 days. Nestling season is about 20 days.

conservation status

Not threatened.

significance to humans

None known.


Red-backed shrike

Lanius collurio

subfamily

Laniinae

taxonomy

Lanius collurio Linnaeus, 1758, Sweden. Up to five races described, but probably best considered monotypic as the supposed and slight differences between races also occur within given local populations all over the breeding range.

other common names

French: Pie-grièche écorcheur; German: Neuntöter; Spanish: Alcaudon Dorsirrojo.

physical characteristics

6.2–7 in (16–18 cm); on average 1.05–1.12 oz (30–32 g). One of the smallest Lanius shrikes; strong sexual dimorphism. The brightly colored male is unmistakable with his gray head, reddish brown upperparts, gray rump, black tail fringed white, and pinkish underside. Female is much duller, but her ground color is variable; brown and gray are dominant; her under-parts are generally heavily vermiculated. Juveniles are very similar to the female but with strong barring, (black crescents), also on upperparts.

distribution

Most widespread and common shrike in the western Palearctic, almost reaching the Arctic circle in the north. In some hot Mediterranean areas, like Spain and southern France, it is regarded as a bird of low mountains. This long-distance migrant winters in eastern and southern Africa, from southwestern Kenya southwards.

habitat

Semi-open habitats dotted with low perches and thorny bushes like hawthorn and blackthorn. Benefits from low-intensity farming, particularly traditional pastures; also found in young plantations, forest clearings, etc. Breeds up to about 6,600 ft (2,000 m) in the French Alps and even up to about 10,500 ft (3,200 m) on meadows in Caucasus. In Africa, it favors arid savannas and particularly dry Acacia thornveld.

behavior

In breeding season, it defends a rather small territory covering 3.7–7.4 acres (1.5–3 ha). At the end of April or beginning of May, when they have returned from Africa, perched males advertise their territories by typical, far-carrying, and somewhat nasal calls. It is a "sit and wait" predator that takes most of its prey on the ground; however, many insects are also caught in the air in fair weather. Larders are kept, but that habit varies among individuals and is less common in warmer climates, where insects are plentiful and easier to locate. Leaves its breeding sites from the beginning of July onward; October observations are rare in Europe. It is a long-distance and a loop migrant; in autumn, west European populations converge towards Greece and its islands before crossing the sea to Egypt, and then to Sudan and Ethiopia; in spring, these two last countries are almost completely avoided as the species passes more to the east, toward the Arabian peninsula.

feeding ecology and diet

Arthropods, mainly insects, particularly beetles and grasshoppers. Small vertebrates constitute about 5% of the captures, but may even be more important in certain years when moles are abundant.

reproductive biology

Monogamous. Densities can be locally high with up to seven pairs, almost loose colonies, per 25 acres (10 ha) in good habitats. Isolated pairs are not rare, however. Nests are built soon after arrival from wintering quarters at an average height of about 4.2 ft (1.3 m) above the ground, often in a thorny bush. In most areas, laying begins at the end of May and peaks in the first two weeks of June. Second broods are very rare, but replacement clutches are frequent. Female usually lays four to six eggs (range one through eight); incubation is 13–15 days exclusively by female, who is regularly fed by male. Nestling period is about 15 days. Young are completely independent when they are about six weeks old.

conservation status

Not threatened, but declining in many countries, particularly at lower altitudes where they have been eliminated by the intensification of agriculture. Climatic fluctuations may also play a role; has disappeared as a regular breeding bird from Britain, which lies on the north-western limits of its range.

significance to humans

In Europe, it is now protected and regarded as a significant bio-indicator of the health of the wider environment. Thousands still are killed on migration, particularly in Greece and in the Middle East.


Long-tailed shrike

Lanius schach

subfamily

Laniinae

taxonomy

Lanius schach Linnaeus, 1758, China. Generally nine races recognized; intermediate forms exist. Variation concerns body and bill size, tail-length, and color of head and upperparts. Closely allied with the gray-backed (or Tibetan) shrike (Lanius tephronotus), but the latter is obviously a distinct species with two races.

other common names

English: Black-headed shrike, Schach shrike, rufous-backed shrike; French: Pie-grièche schach; German: Schachwürger; Spanish: Alcaudon Cabecinegro.

physical characteristics

9–10.6 in (23–27 cm); on average 1.76–1.86 oz (50–53 g) for nominate and about 1.3 oz (37 g) for erythronotus. Nominate, which inhabits China, is the largest race. Sexes similar or nearly so. Head and mantle are dark gray, back and rump are rufous; tail is long, black, and graduated; wings are dark with conspicuous white primary patches. Underparts are whitish, strongly tinged with rufous on the sides of breast and flanks. Erythronotus, widespread in central Asia and in the Indian subcontinent, is similar, but distinctly smaller, somewhat duller, and with a narrower black band on the forehead. Caniceps from southern India and Sri Lanka is paler, with less rufous on its upperparts. Race tricolor is a superb Himalayan bird; it bears a black cap, shows a small grayish area on upper mantle, and has mainly deep rufous upperparts. It is rather similar to the three insular races. Race longicaudatus from Thailand has a very long tail. Remarkably, in certain areas, nominate has a melanistic form called fuscatus; mixed pairs have been recorded.

distribution

Has a vast breeding area, from central Asia, Turkmenistan, and possibly Iran, to the Chinese Pacific coast, Southeast Asia, and New Guinea.

habitat

A scrub jungle bird, but also associated with lightly wooded country, cultivated areas, and gardens. Generally a bird of lowlands, but in the Himalayas, tricolor populations have been found up to 9,800 ft (3,000 m) and occasionally up to 14,000 ft (4,300 m). Nominate breeds up to 9,800 ft (3,000 m) in China.

behavior

Solitary in habits, and highly territorial. Densities can, however, be very high locally with up to 1.6 pairs/acre (4 pairs/ha) in suburban areas in Afghanistan. It is very vocal in the breeding season during pair formation. It takes most of its prey on the ground, but also hawks insects in the air and occasionally pirates other birds. Impales some of its victims. Most populations are resident; however, local movements, including altitudinal ones, are known. The western part of the breeding range, covering central Asia, is almost completely vacated by erythronotus between August and November; the birds return in late February.

feeding ecology and diet

Arthropods, mainly insects; also small vertebrates and occasionally fruits.

reproductive biology

Monogamous. The cup-shaped nest is rather bulky and placed in a thorny bush or in a tree; it is hidden 9.8–39.4 ft (3–12 m) above the ground. There appears to be a geographical variation in clutch size: four to six eggs in China, four in Sri Lanka, three in the Malay Peninsula, and two in New Guinea. Breeding season varies with geographical areas; the western race lays eggs between the end of March and July. Locally double-brooded; replacement clutches are frequent. Incubation by female lasts 13–16 days, and the young fledge after 14–19 days.

conservation status

Not threatened.

significance to humans

In Nepal, its bill is used to "feed" newborn babies; this ceremony is supposed to bring luck to the young children.


Loggerhead shrike

Lanius ludovicianus

subfamily

Laniinae

taxonomy

Lanius ludovicianus Linnaeus, 1766, Louisiana. Up to 12 races described; some of them poorly differentiated. Variation affects size and plumage coloration, particularly of the back and underparts.

other common names

English: Migrant shrike; French: Pie-grièche migratrice; German: Louisianawürger; Spanish: Alcaudon Yanqui.

physical characteristics

About 8.2 in (21 cm); on average 1.7 oz (48 g). The loggerhead is relatively large, large-headed, gray, black, and white shrike; sexes are similar or nearly so. Facial mask extends just over the eyes. Upperparts are gray with white scapulars. Wings and tail are mainly black, but with a white primary patch and white outer tail feathers. Underparts are white, sometimes with faint indications of barring. Juveniles are similar, but paler, brownish gray, and barred overall. Nominate, common in southeastern United States, is dark gray above, including on rump, and almost pure white below, whereas excubitorides from the Great Plains region of the west is a pale race with a white rump. The endangered race mearnsi, confined to the San Clemente Island of California, is a darker gray than any other subspecies on it upperparts. The loggerhead shrike resembles the northern shrike, but the latter is about 25% larger, paler gray above, and with a facial mask not extending over the eyes, and particularly narrowed in lores.

distribution

Only endemic shrike in North America, from southern Canada to Mexico. Northern part of breeding range is vacated in winter; contacts then possible with the relatively similar northern shrike, which also migrates further south from its breeding grounds in Alaska and northern Canada.

habitat

Various types of semi-open habitats with short vegetation; pastures are favored in many areas in Missouri, Illinois, and New York. In the western part of its range, it also occurs in semiarid sagebrush areas, desert scrub, and pinyon-juniper woodlands; may occur in residential areas that are well dotted with perches. May be present in mountainous areas up to about 6,600 ft (2,000 m).

behavior

Usually solitary or in pairs, but curious group meetings have been reported. Size of territory varies with habitat quality and averages about 25 acres (10 ha), but appears to be three times as large in the rare San Clemente race. Territory is defended with loud song and harsh territorial calls that may be produced in flight. It hunts from an elevated perch (6.6–33 ft [2–10 m]) and catches most of its prey on the ground. Impaling is regular; prey weighing more than about 1.1 oz (30 g) may be carried in the feet. Populations nesting north of about 40°N migrate and may move into areas with resident birds; most leave between September and November and return in March or April. In some southern areas, pairs maintain territories throughout the year; but in others, they separate and often defend adjacent territories.

feeding ecology and diet

All kinds of arthropods, mainly insects, most commonly beetles and grasshoppers. Vertebrate prey is regularly taken, particularly in winter; it includes small birds, lizards, mice, and occasionally bats and fish.

reproductive biology

Territorial and normally monogamous. Even in well-populated areas, nests are normally several hundred yards (meters) apart, but small colonies have been reported occasionally. Northern populations are single-brooded, whereas second broods are common and third broods occasional in southern areas, such as Florida. Replacement clutches are frequent everywhere. Female usually lays four or five eggs (ranges one through seven); clutch size seems to vary with latitude. Female alone incubates for about 16 days; she is fed in the nest by the male. Nestling period is 16–21 days according to weather conditions. The young are independent four to five weeks after fledging, but they may stay up to three months with the parents.

conservation status

Not threatened yet, but populations have experienced a marked decline in many regions, particularly in the northern part of the range. It is classified as endangered in Quebec. The highly endangered San Clemente race benefits from strong conservation measures; these measures include eradication of predators, removal of herbivores that tend to destroy the habitat, and breeding in captivity in the San Diego Zoo for reinforcement operations.

significance to humans

Of high significance to North American conservationists, as it is declining dramatically in most parts of range.


Resources

Books

BirdLife International. Threatened birds of the world. Barcelona and Cambridge: Lynx Edicions and BirdLife International, 2000.

Fry, C.H., S. Keith, and E.K. Urban, eds. The Birds of Africa. Vol. 6. London: Academic Press, 2000.

Harris, T. Shrikes and Bush-shrikes. Princeton and Oxford: Princeton University Press, 2000.

Lefranc, N., and T. Worfolk. Shrikes. A Guide to the Shrikes of the World. New Haven and London: Yale University Press, 1997.

Yosef, R., F. Lohrer, D. Van Nieuwenhuyse, and P. Busse, eds. Proceedings of the Third International Shrike Symposium, 15-18 September 2000, Gdansk, Poland. Choczewo: The Ring; Polish Zoological Society, 2001.

Periodicals

Burgess, N., T.S. Romdal, and M. Rahner. "Forest Loss in the Ulugurus, Tanzania and the Status of the Uluguru Bush-Shrike Malaconotus alius." Bull. ABC 8 (2001): 89–90.

Kristin, A., H. Hoi, F. Valera, and C. Hoi. "Breeding Biology and Breeding Success of the Lesser Grey Shrike Lanius minor in a Stable and Dense Population." Ibis 142 (2000): 305–311.

Schollaert, V., and G. Willem. "A New Site for Newton's Fiscal Lanius newtoni." Bull. ABC 8 (2001): 21–22.

Van Nieuwenhuyse, D. "Global Shrike Conservation; Problems, Methods and Opportunities." Aves 36 (1999): 193–204.

Organizations

International Shrike Working Group. "Het Speihuis," Speistraat, 17, Sint-Lievens-Esse (Herzele), B-9550 Belgium. Phone: +32 54 503 789. E-mail: [email protected]

Norbert Lefranc, PhD

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