Great grey shrike

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Great grey shrike
prey propped up on a thorn

Least Concern (IUCN 3.1)[1]
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Passeriformes
Family: Laniidae
Genus: Lanius
Species:
L. excubitor
Binomial name
Lanius excubitor
Subspecies

See text

Native range of L. excubitor, Resident in red, breeding in yellow, non-breeding in green, and passage migrant in blue.

The great grey shrike (Lanius excubitor) is a large and

parapatric southern relatives, the Iberian grey shrike (L. meridionalis), the Chinese grey shrike (L. sphenocerus) and the American loggerhead shrike
(L. ludovicianus). Males and females are similar in plumage, pearly grey above with a black eye-mask and white underparts.

Breeding takes place generally north of

temperate regions.[2] The great grey shrike is carnivorous, with rodents
making up over half its diet.

Taxonomy and systematics

The species was first

binomial name. His description is L[anius] cauda cuneiformi lateribus alba, dorso cano, alis nigris macula alba – "a shrike with a wedge-shaped white-bordered tail, back grey, wings black with white spot".[3] At that time, none of the other grey shrikes – including the lesser grey shrike
(L. minor), for which the description of the tail pattern is incorrect and which some authors already recognized as distinct – were considered separate species by Linnaeus, but that was to change soon.

Linnaeus' binomial name replaced the cumbersome and confusing descriptive names of the earlier

type locality of Linnaeus is simply given as Europa ("Europe").[4]

The scientific name of the great grey shrike literally means "sentinel butcher": Lanius is the Latin term for a butcher, while excubitor is Latin for a watchman or sentinel.[5] This refers to the birds' two most conspicuous behaviours – storing food animals by impaling them on thorns, and using exposed tree-tops or poles to watch the surrounding area for possible prey. Use of the former by Conrad Gessner established the quasi-scientific term lanius for the shrikes. Linnaeus chose his specific name because the species "observes approaching hawks and announces [the presence] of songbirds"[6] as he put it. This habit was also put to use in falconry, as fancifully recorded by William Yarrell later.[7] The common English name "shrike" is from Old English scríc, "shriek", referring to the shrill call.[8]

Vernacular names

vagrant) as well as Warkangel, Werkengel or Wurchangel in various German dialects (e.g. around Frankfurt and Strasbourg) probably mean "choking angel" (cf. Standard German Würgeengel). These names are unlikely to significantly pre-date the times of Saint Boniface (c. 700 AD) because of their Christian connotation; the related Werkenvogel ("choking bird") might, however, do so. The English version, having become wariangle or weirangle, was eventually transferred to the native red-backed shrike (L. collurio) and lingered on into modern times in Yorkshire. Along the upper Rhine, between Strasbourg and Heidelberg for example, Linkenom is attested; its origin is unclear. Low German Neghen-doer and Middle German Nünmörder were also used; this has today evolved into Neuntöter and specifically means the red-backed shrike, but could in earlier times refer to any native Lanius
. It literally means "killer of nine [prey animals]" and refers to the food caches.

A

French Jura. In Norway a vernacular name for the bird is varsler.[9] A whimsical name – presumably from Scotland or nearby England – was "white wisky John" in reference to its wavy and somewhat unelegant flight, during which its large areas of light plumage are conspicuous.[10]

The "grey shrike" is also sometimes named "gray shrike."[11]

Relationships and evolution

The shrike

Bergmann's Rule, the smallish fossil makes an unlikely ancestor to the large grey shrikes even when taking into account the somewhat warmer Miocene climate.[12]

The grey shrike

phylogenetic uncertainties surrounding this close-knit group in the absence of a good fossil record, some refrain from splitting them up into distinct species; most modern authors do so however.[1][13]

Subspecies

L. e. "melanopterus" wintering in Poland
Indian great grey shrike
Lanius excubitor ssp. lahtora

There are a number of subspecies:[14]

  • Lanius excubitor excubitor (including melanopterus – which may intergrade with sibiricus – and galliae) – breeds in temperate to subarctic continental Europe and northwest Siberia
Medium grey above, pale grey hue below; some white on primaries and sometimes secondaries
  • Lanius excubitor homeyeri – breeds in southeast Europe and southwest Siberia
Lighter grey than excubitor above, dull white below; more white on primaries and secondaries
  • Lanius excubitor koenigi – endemic to the Canary Islands
  • Lanius excubitor algeriensis – coastal northwestern Africa
  • Lanius excubitor elegans – Eastern Morocco, northeastern Mauritania and northwestern Mali to northeastern Sudan, Egypt and southwestern Israel
  • Lanius excubitor leucopygos – central and southern Mauritania to southern Chad and central Sudan
  • Lanius excubitor aucheri – east-central Sudan to northwestern Somalia northwest to Iraq and Iran
  • Lanius excubitor theresae – southern Lebanon and northern Israel
  • Lanius excubitor buryi – endemic to Yemen
  • Lanius excubitor uncinatus – endemic to Socotra
  • Lanius excubitor lahtora – Pakistan through central India and southern Nepal to western Bangladesh
  • Lanius excubitor pallidirostris (Steppe grey shrike) – Central Asia and parts of northern China, Iran, Afghanistan and Pakistan

Description

An adult great grey shrike is a medium-sized passerine about as large as a big

nominate subspecies adult weights between 48 and 81 g (1.7 and 2.9 oz) are recorded. The wings are around 11.4 cm (4.5 in) and the tail around 10.9 cm (4.3 in) long in the nominate subspecies, its bill measures about 23 mm (0.91 in) from tip to skull, and the tarsometatarsus part of its "legs" (actually feet) is around 27.4 mm (1.08 in) long.[15] Wingspan can range from 30 to 36 cm (12 to 14 in).[16]

Adult male (top) and female L. e. excubitor with fledging young (bottom)

The general colour of the upperparts is pearl grey, tinged brownish towards the east of its Eurasian range. The cheeks and chin as well as a thin and often hard-to-see stripe above the eye are white, and a deep black mask extends from the

North Pacific in particular and in females elsewhere too, there may be faint brownish bars on the breast. The bill is large and hooked at the tip and coloured nearly black, but pale at the base of the under mandible (though the extent varies seasonally). The legs and feet are blackish.[17]

Males and females are about the same size, and do not differ conspicuously in appearance except by direct comparison. In the female the underparts are greyer and are usually visibly barred greyish-brown, and the white wing and tail markings are characteristically less in extent (though this is rarely clearly visible except in flight).

moult into a female-like plumage with the tertiary bars usually remaining in autumn. Across its range, the young acquire the adult plumage in their first spring.[18]

Vocalizations

The male's

territory – be it a female or male of its species or a large mammal – it gives long shrill raspy whistles like trrii(u) or (t')kwiiet. To announce to females, it often mixes these whistles with a strophe of song. A softer whistle goes like trüü(t). These whistles are also used in duets between mates in winter and neighbours in the breeding season. Various contact calls have been described as chlie(p), gihrrr, kwä or wuut. These are frequently heard during courtship, interspersed with song phrases as the harsh whistles are in pre-courtship. The song becomes softer and more warbling as the male shows the female around his territory, and at potential nest sites the male gives a lively chatter containing fluting tli-tli, prrr trills and kwiw...püh calls.[19]

When disturbed, its alarm note is a harsh jay-like k(w)eee, greee or jaaa, often repeated twice. The more excited the birds become, the higher and faster the calls get, via chek-chek-chek to a rattle trr-trr-trr or an explosive aak-aak-aak. A bird of prey alert is given with a whistle breezeek. Knuk calls are given by adults confronted with a potential threat to their young. To beg for food – young to adults or mates to each other – rows of waik calls are given. This species sometimes tries to attract small songbirds by mimicking their calls, so it may attempt to catch them for food.[20]

Similar species

The

millennia).[21]

Loggerhead shrike
Lanius ludovicianus

Elsewhere, the

superspecies between Eastern Europe and Central Asia; it may be more closely related to the small brown shrikes and resemble the bold, aggressive and hard-to-catch grey shrikes because of Batesian mimicry.[22]

Lesser grey shrike
Lanius minor

The Iberian grey shrike is clearer and usually darker grey above, and not tinged grey but often decidedly pinkish on the belly and particular breast; the white "eyebrow" extends to over the beak, which has typically a larger pale base. The barring pattern is less developed at all ages, hardly ever present even in females, and slighter in the otherwise very similar

fledglings.[23]

East Asian L. excubitor are barely sympatric with the Chinese grey shrike. The latter is larger and generally differs from the northern species as the southern does, and in addition has much larger white areas in wings and tail.[24]

The loggerhead shrike is hard to distinguish, but the proportion of the head to the beak (which seems stubby in L. ludovicianus by comparison and is all-dark) is usually reliable. Indeed, the word loggerhead refers to the relatively larger head of the southern species.[25]

The lesser grey shrike is a smaller and comparatively short-tailed bird. It can best be recognized by the rather large black area above the bill, almost reaching to the forehead and without a white stripe above it. In flight, the wide instead of pointed black tail end of L. minor is characteristic. The African species are completely

allopatric with L. excubitor; they lack white scapulars (grey-backed fiscal) or wingspots (Mackinnon's fiscal) and differ in some other details, particularly the tail pattern.[26]

Distribution and habitat

Generally, its breeding range is found in Eurasia and northern Africa. In the high mountains of the

vagrant in Iceland, the British Isles, the Mediterranean region (excluding the Iberian Peninsula and perhaps Romania but including Cyprus), and Korea. There do not appear to be breeding records from the entire Kamchatka Peninsula; in Switzerland, the present day Netherlands and southern Germany small populations were found in the mid-20th century but have declined or even disappeared since then.[27]

Except for the

parapatric to it. The populations of the Central Asian mountains mostly migrate downslope rather than southwards. Females are more prone to migration than males; they do not appear to migrate, on average, longer or shorter distances than males, and consequently are the dominant sex in many parts of the winter range. Birds leave for winter quarters a more or less short time after breeding – July to October, with most birds staying to September – and return to nest mainly in March/April, but some only arrive in May. In recent decades, the number of birds remaining on the breeding grounds all year has been noted to increase e.g. in Fennoscandia, whereas for example borealis seems to be as rare a winter visitor in northern Ohio as it was a century ago.[2][28][29]

The preferred

microhabitat desires, but little detail is known yet.[30]

Behaviour

Perching sites are important features of great grey shrike habitat

This species is

ephemerally. This leads to shifts in population density between regions, as "floaters" move between groups of territorial birds in search of a bountiful unclaimed territory to settle down and/or a partner to mate with. On the wintering grounds, pairs separate to account for the lower amount of food available at that time, but if both members migrate they tend to have their wintering grounds not far apart. As it seems, once an individual great grey shrike has found a wintering territory it likes, it will return there subsequently and perhaps even try to defend it against competitors just like a summer territory. Throughout the year, the birds regularly but briefly move through a range up to three times larger than their territory; this is tolerated by territory owners in winter more easily than in summer, and the parts of Europe where all-year residents and winter visitors co-occur typically have population densities around eight[verification needed] birds/km2 (about thirty[verification needed] per square mile) and occasionally more in winter.[31]

Lasy Janowskie
, Poland

Before and after the nesting season, groups of breeding birds will sometimes initiate gatherings; these seem to occur at the boundary of the group's combined range or in the unclaimed land separating it from neighbouring groups. The initiation signal is a conspicuous display flight given by a bird surveying its territory: it spirals tens of meters/yards high into the air, usually briefly does a fluttering hover at the top of the spiral, and then glides down. Group neighbours will respond by performing the same type of flight, and eventually about half the group's members will depart to the meeting location where they will spend several tens of minutes – sometimes more than an hour – chattering, calling, duetting, and excitedly moving about the meeting site (which typically is some small tree or shrubbery). In winter, birds will often assemble in small groups and roost together, particularly to keep warm during the night; this is apparently not initiated with a specific assembly display however.[32]

The flight of the great grey shrike is undulating and rather heavy, but its dash is straight and determined. It is, as noted above, also capable of

submission gesture to prevent an imminent attack by a conspecific is pointing the beak straight up.[33]

Fledgelings moult part of their juvenile plumage before their first winter, and the rest in spring. Adults moult on their breeding grounds before going on migration, or before the depth of winter if they are resident. Sometimes adults also seem to moult some feathers before attempting to breed. As moult requires a considerable investment of energy, some significant

parasite load, moulting can make a bird more physically attractive and healthy, and may thus increase its chance of successful reproduction. The phenomenon is not well understood, however.[2]

Food and feeding

Occasionally, animals as large as a young stoat (Mustela erminea) are killed and eaten by great grey shrikes

The great grey shrike eats small vertebrates and large invertebrates. To hunt, this bird perches on the topmost branch of a tree, utility pole or similar elevated spot in a characteristic upright stance some metres/yards (at least one and up to 18 m/20 yd) above ground. Alternatively, it may scan the grassland below from flight, essentially staying in one place during prolonged bouts of mainly hovering flight that may last up to 20 minutes. It will drop down in a light glide for terrestrial prey or swoop hawk-like on a flying insect. Small birds are sometimes caught in flight too, usually by approaching them from below and behind and seizing their feet with the beak. If no prey ventures out in the open, great grey shrikes will rummage through the undergrowth or sit near hiding places and flash their white wing and tail markings to scare small animals into coming out. As noted above, it will sometimes mimic songbirds to entice them to come within striking distance.[32]

Bumblebee (Bombus lucorum or B. terrestris) stuck on barbed wire in a great grey shrike's "larder"

Typically, at least half the prey

Prey is killed by hitting it with the hooked beak, aiming for the skull in vertebrates. If too large to swallow in one or a few chunks, it is transported to a feeding site by carrying it in the beak or (if too large) in the feet. The feet are not suited for tearing up prey, however. It is rather impaled upon a sharp point –

elytra of beetles are eaten and later regurgitated as pellets.[32][36]

The basic

body mass. An adult of this species needs about 50 g (1.8 oz) of prey a day, probably somewhat more in winter. Under most circumstances, this would thus translate to one or two rodents, one or two additional vertebrate prey animals (including rodents), and up to a single vertebrate prey item's worth of invertebrates. Surplus food may be impaled for storage. These "larders" are typically around 1 m (3.3 ft) above ground and can be found anywhere within the birds' territory, but tend to be rather in the general vicinity of nest sites than far away from them.[32][37]

Breeding and life history

Great grey shrikes breed during the summer, typically once per year. In exceptionally good conditions, they raise two broods a year, and if the first

courtship period is generally longer than in the Iberian grey shrike (L. meridionalis), usually starting about March and lasting to April/May. At first, the female rebuffs the male, only allowing him to feed her. Males give increasingly vocal displays and show off the white markings of the wings in flight and of the tail by fanning it and turning away from the female. He also occasionally turns to sit at a right angle to her. Eventually, the female will join in the male's displays, and the songs will become duets. To feed females and to show off their hunting prowess, males will make their food caches in conspicuous places during this time. When presenting nesting sites, males give the variety of calls described above and jerk their head and fanned tail.[38]

predators

Copulation is typically initiated by the male bringing an attractive prey item to the female. With both giving begging calls, they approach until they are side by side. The male then raises and swings his body left and right a few times, and passes the prey to the female, followed by the actual copulation. The gatherings of neighbour groups (see above) cease when nesting is underway, and when the eggs are nearly ready to lay, the male guards his partner closely, perching higher than her to watch for threats and frequently feeding her. This apparently ensures her physical well-being rather than preventing extra-pair copulations, as neighbouring males will stray through each other's territory to snatch a quick fling with the resident females. In this, they have almost a one-in-three chance of success, and consequently the average grey shrike nest is very likely to contain offspring of more than one male. Females may deposit their eggs in neighbours' nests, but this seems to occur more rarely; in general, mated females are fairly reclusive after their eggs have started developing. A full clutch of eggs can be produced by a female in about 10–15 days.[38]

cup nest is quite sizable, measuring 20–28 cm (7.9–11.0 in) in outer diameter. Its body is constructed of coarse vegetable material – mainly large twigs and chunks of moss, though bits of fabric and rubbish may be added. The interior cup is 8–12 cm (3.1–4.7 in) in diameter and 10–15 cm (3.9–5.9 in) deep; it is lined with fine twigs and roots, lichen, hair and feathers. Building a nest from scratch takes a pair one to two weeks, but if nests of the previous year in good locations remain usable, they are repaired rather than discarded.[39]

reed-warblers (Acrocephalus), the great grey shrike seems to have out-evolved the common cuckoo
(Cuculus canorus) for the time being
MHNT
MHNT

Laying usually takes place in May. The clutch numbers three to nine eggs, typically around seven, with North American clutches tending to be larger on average than European ones. If a second clutch is produced in one breeding season, it is smaller than the first one. The eggs have a white background colour, usually with a grey hue and sometimes with a blue one; they are patterned with blotches of yellowish- to reddish-brown and purplish-grey, often denser around the blunt end. They measure around 26 mm (1.0 in) in length and 19.5 mm (0.77 in) in width.

nestlings hatch naked, blind and pink-skinned, weighing c. 4 g (0.14 oz); their skin turns darker after a few days. The inside of their beak is pink and they probably lack spots or other prominent marks; the wattles at the corners of the mouth are yellow as in many passerines. As the nestlings grow, the female broods them, and later on assists in providing food. The young fledge after 2–3 weeks, typically in late June or early July; they become independent of their parents about 3–6 weeks later. Sometimes, a parent will single out particular fledglings (possibly the weakest ones) and focus their care and feeding on these during this time. Other adults have occasionally been recorded assisting in feeding a pair's offspring; it is not clear whether these helpers at the nest are offspring of previous years, or unrelated non-breeding "floaters" or breeding neighbours.[37][39]

corvids (Corvidae) – extremely close relatives of the shrikes (Laniidae) as it happens[40] – are most significant.[39]

Usually more than half of all nests manage to hatch at least one young, and around three-quarters of all eggs laid hatch, suggesting that if eggs are lost before hatching, it usually is the entire clutch. Half to three-quarters of the hatched young successfully fledge under most circumstances. They will become sexually mature in their first spring and often attempt to breed right away. On average, great grey shrikes get a chance at four breeding attempts during their life, with most birds in the wild getting eaten by a

carnivorous mammal or dying of other causes before the end of their fifth winter. Raptorial birds are the main threat to shrikes after fledging, with regular predators including species as small as little owls (which are close to the same size as the shrike).[41] The maximum documented lifespan, however, is 12 years.[37][42]

Conservation status

As remarked

predatory bird, the indiscriminate use of pesticides (which will accumulate in adult carnivores and inhibit breeding success) around the 1960s probably had a detrimental influence on stocks too.[30]

Altogether, the great grey shrike is common and widespread and not considered a

L. meridionalis in L. excubitor). Wherever it occurs, its numbers are usually many hundreds or even thousands per country. Its stronghold is the region around Sweden, where at least almost 20,000, perhaps as many as 50,000 were believed to live in the late 20th century. However, in some countries it is not robustly established; in Estonia only a few hundred are found, with less than 200 in Belgium and some more or less than 100 in Latvia and Lithuania, respectively. The 10 birds or so in Denmark might disappear because of a few years of adverse circumstances. By contrast, in Luxembourg plentiful high-quality habitat is found; though the number of great grey shrikes in this tiny country is necessarily limited, the average population density there is 25 times as high as in Lithuania.[1][30]

Footnotes

  1. ^ . Retrieved 21 February 2022.
  2. ^ a b c Harris & Franklin (2000): pp. 152–153
  3. ^ Linnaeus, Carl (1758). Systema Naturæ per regna tria naturae, secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis (in Latin). Vol. 1 (10th ed.). Holmiae (Stockholm): Laurentii Salvii. p. 94.
  4. ^ Aldrovandi (1646), Willughby (1676): p. 53, Ray (1713), Frisch (1720[verification needed]), Albin (1731–1738), Linnaeus (1746, 1758)
  5. .
  6. ^ Accipitres adventantes observat & aviculis indicat: Linnaeus (1758)
  7. ^ Gessner (1555): p. 557, Linnaeus (1758), Glare (1968–1982): pp. 637, 1000, Swainson (2008): p. 47
  8. ^ "Shrike". Oxford English Dictionary (Online ed.). Oxford University Press. (Subscription or participating institution membership required.)
  9. ^ "Lanius excubitor". Natural History Museum, University of Oslo, Norway Bird Collection. Naturhistorisk museum. Retrieved 18 February 2018.
  10. ^ Gessner (1555): p. 557, Aldrovandi (1646), Willughby (1676): pp. 52–53, Ray (1713), Swainson (2008): p. 47
  11. ^ For instance: at ebird.org and birdsoftheworld.org (accessed 2022-05-05).
  12. ^ Harris & Franklin (2000): pp. 24–25, Mlíkovský (2003): pp. 233, 251, Jønsson & Fjeldså (2006)
  13. ^ Harris & Franklin (2000): pp. 24–25, Sangster et al. (2002)
  14. ^ Gill, Frank; Donsker, David, eds. (2017). "Shrikes, vireos & shrike-babblers". World Bird List Version 7.3. International Ornithologists' Union. Retrieved 28 October 2017.
  15. ^ Harris & Franklin (2000): pp. 150, 155
  16. ^ "Northern Shrike, Life History, All About Birds – Cornell Lab of Ornithology". Allaboutbirds.org. Retrieved 2013-03-10.
  17. ^ Harris & Franklin (2000): pp. 60–61, 150–151
  18. ^ Harris & Franklin (2000): pp. 60–61, 151–152
  19. ^ Harris & Franklin (2000): pp. 153–155
  20. ^ Harris & Franklin (2000): pp. 154
  21. ^ Harris & Franklin (2000): pp. 150–151, Sangster et al. (2002)
  22. ^ Harris & Franklin (2000): pp. 24–25, 151
  23. ^ Clement & Worfolk (1995), Tenuvuo & Varrela (1998), Harris & Franklin (2000): pp. 62–63, 150–151
  24. ^ Harris & Franklin (2000): pp. 58, 151
  25. ^ Harris & Franklin (2000): pp. 64–65,151
  26. ^ Harris & Franklin (2000): pp. 58–59, 66–67, 151
  27. ^ Keller, Herrado, Voříšek et al.
  28. ^ Henninger (1906)
  29. ^ Ohio Ornithological Society (2004): Annotated Ohio state checklist Archived 2004-07-18 at the Wayback Machine.
  30. ^ a b c Harris & Franklin (2000): p. 152
  31. ^ a b Harris & Franklin (2000): pp. 153–154
  32. ^ a b c d Harris & Franklin (2000): p. 153
  33. ^ Harris & Franklin (2000): pp. 150, 153
  34. ^ "Lanius excubitor (Great grey shrike)". Animal Diversity Web.
  35. ^ "Lanius excubitor (Great grey shrike)". Animal Diversity Web.
  36. ^ a b Antczak et al. (2005)
  37. ^ a b c AnAge [2009]: Lanius excubitor life history data. Retrieved 2009-SEP-19.
  38. ^ a b Harris & Franklin (2000): pp. 154–155
  39. ^ a b c Harris & Franklin (2000): p. 155
  40. ^ Jønsson & Fjeldså (2006)
  41. JSTOR 4088571
    .
  42. ^ Harris & Franklin (2000): p. 154

References

External links