Isabelline Shrike (Lanius isabellinus)

Isabelline Shrike

[order] PASSERIFORMES | [family] Laniidae | [latin] Lanius isabellinus | [UK] Isabelline Shrike | [FR] Pie-grieche | [DE] Isabellwurger | [ES] Oropendola | [NL] Isabelklauwier

Subspecies

Genus Species subspecies Breeding Range Breeding Range 2 Non Breeding Range
Lanius isabellinus EU c s Asia, e AF
Lanius isabellinus arenarius
Lanius isabellinus isabellinus
Lanius isabellinus tsaidamensis

Physical charateristics

Rather small, compact but still long-tailed shrike, with behaviour of Red-becked Shrike but plainest plumage of all west Palearctic Lanius: only obvious features are rufous lower rump and tail and, in adult male, dark face-patch and white patch on primaris.Sexes dissimilar, no seasonal variation.

wingspan min.: 24 cm wingspan max.: 27 cm
size min.: 17 cm size max.: 19 cm
incubation min.: 14 days incubation max.: 16 days
fledging min.: 0 days fledging max.: 16 days
broods: 1   eggs min.: 4  
      eggs max.: 6  

Range

Eurasia : Central

Habitat

Breeds in east Palearctic, in continental lower middle latitudes, in mountains up to 3500 m, but also on hills and barren plains. Nest in tamarisk thickets in river valleys, patches of scrub in dry steppe, and on edge of pistachio grove. Winters on edges of cultivation in semi-desert and among sparse and tamarisk.

Reproduction

The males generally arrive on the territories of nesting a few days before the females. Couples are likely to be formed during migration. The egg laying starts at the end of April in the south of Turkmenistan, two to four weeks later in North of Kazakhstan. Only little information is available on breeding behavior in the nominate race isabellinus. The laying starts in mid-April and continues until June. The nomimate might have a second brood but this needs confirmation.
The nesting site is chosen by the male. The male will try to draw attetion of a female during nest building. if she is interested the female will assist in nest building which finishes usually in a few days. The nest is built in thorny bushes and seldom in small trees. The majority of the nests are located at 1 m above the ground, but they can be placed between 3 and 5 meters in trees such as the pistachio trees. The nest is built with whatever materials are available the diameter vary from 9 to 20 cm and 4 to 10 cm deep. The clutch size varies in subspecies but is between 3 and 7 eggs. In all races, the female incubates during 13 to 17 days. The young fledge after 13 to 16 days. The nests of subspecies L. phoenicuroides are parasitized by the gray cuckoo (cuculus canorus). In the Lake Balkash area, 13 out of 90 nests underwent this phenomenon.

Feeding habits

Adult and larval insects, mainly beetles. Also other invertebrates and small vertebrates. sits on prominent look-out perch and glides down onto ground prey or pursues flying insects and small passerines.
Takes beetles at animal droppings or carrion.

Conservation

This species has an extremely large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence <20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). The population trend appears to be stable, and hence the species does not approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size has not been quantified, but it is not believed to approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern.
Occurs only as a migrant in west Palearctic. Accidental in Britain, Ireland, France, West Germany, Norway, Sweden, Finland, Poland, Spain, Egypt. Very little information available.
Isabelline Shrike status Least Concern

Migration

All populations migratory, wintering from north-west India and Afghanistan through southern Middle East to sub-Saharan Africa west to Nigeria and south to Tanzania. Heading in autumn varies between south-west (for most birds) to Africa, and south to south-east to India, while birds wintering in Nigeria must head almost due west within Africa. Return migration in spring apparently by same routes. A regular autumn passage migrant through Iraq; occasional in Israel and Sinai in spring.
In Britain and Ireland, c. 29 records 1958-89, 25 of them September-November and only 2 in spring; almost annual since 1975, but before then not treated as separate species so many earlier occurrences undocumented; up to 7 in one year (1988); recorded mainly Shetland and east coast, those in south-west having probably moved within Britain. Other northern and western European records all in autumn.

Distribution map

Isabelline Shrike distribution range map

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