Bulletin 38 - July 1989: Status of Great Grey Shrike (Lanius excubitor) in the UAE
Status of Great Grey Shrike (Lanius excubitor) in the UAE
by C. Richardson
The Great Grey Shrike Lanius excubitor is a widespread and well-known resident in the UAE. It also occurs as a migrant, and is generally believed to be a winter visitor throughout the Arabian peninsula. It is catholic in its taste of habitat, found in a number of varying and diverse haunts throughout most of the year, though is notably absent on higher mountain slopes, featureless sabkha plains and heavily built-up areas. Little is known of the origins of migrant Great Grey Shrikes which occur in the UAE, or indeed the precise timings of their passage over the southern Gulf region. L. e. aucheri is the most commonly occurring race in the UAE, recorded as both resident and migrant, while the north Iranian sub-species L. e. pallidirostris is most common on passage (Hollom, Porter et al 1988). It is best not to linger too long here on the subject occurring races, but this note might serve to alert observers of their occurrence and the difference often visible in the field. Records noting the field characteristics will provide further evidence of passage timings, contributing further information to current knowledge of its status in the region.Occurrence in Nearby Areas
Oman, Saudi Arabia, Qatar and Bahrain have resident populations of Great Grey Shrike, and all record evidence of passage.
Oman: Passage migrants and winter visitors present July to March, residents nest from January. Origins have been identified from sub-species aucheri, pallidirostris and lahtora which have all been recorded there on passage (Gallagher and Woodcock 1980).
Eastern Saudi Arabia: Breeding resident, winter visitor and passage migrant.
Qatar: Present all the year, and common on passage and post-breeding dispersal mid summer. Indian race believed to occur in winter (Qatar National Museum Journal, February 1985).
Bahrain: Breeds in small numbers, fledglings March-May. Recorded as numerous in March, though more evidence of passage August and September (Bahrain Natural History Society).
Das Island (UAE, 165 km. WNW Abu Dhabi town): Available records of daily observations by Len Reaney on the island late 1985 to mid 1987 indicate passage. Single birds were recorded in October and November 1986 and in mid and late March 1987, and two birds were present in September 1986 and on 27 March 1987. No other sightings were documented during this period.
Its general Gulf status is summarised in A Check-list of the Birds of the Arabian Gulf States (Bundy and Warr 1980) as "regular on passage in March, though more common August to October. Small numbers winter November to February. Eggs late January to April." UAE status is absorbed into this check-list from observations made between 1952 and 1980, mostly in Sharjah, Ras al Khaimah and Al Ain. In those days records were kept of birds occurring in a harsher (and more natural) landscape, though undoubtedly with a paucity of observers. Few studies were made in Dubai or Abu Dhabi where favourable habitat has since increased, and observers are now relatively concentrated.
By way of sorting out this species, all personal records of Great Grey Shrike were analysed during the period from 1984 to 1988. The statistics proved interesting and further evidence of the species' movements emerged when records concentrated on one study location.
The Choice of One Study Location
There are several exceptional sites close to Dubai, most of which support small populations of Great Grey Shrike and which provide a variety of habitat from the enriched wetlands of the Zabeel water treatment plant to the desert woodland of Mushrif National Park. Undoubtedly the most interesting place, with the greatest variety of habitat and species, is Saffa Park.
Situated 10 km from Dubai city centre this park was born from a 72 hectare rectangular plot of sandy scrub and sabkha flats. It was chosen by the Dubai municipal authorities in 1976 as the site for Saffa Park, and by 1978 its open grassland and scattered trees was attracting large numbers of migrants. By 1985 over 230 species had been recorded there, including a number of UAE residents such as Grey Francolin Francolinus pondicerianus, Palm Dove, Ring-necked Parakeet, Indian-Roller Coracias benghalensis, Crested Lark, Red-vented Bulbul Pycnonotus cafer, GracefuI Warbler Prinia gracilis, Purple Sunbird, Great-grey Shrike, Common Mynah, House Sparrow and Indian Silverbill Eudice malabarica.
Of those, the species nesting in the park included Palm Dove, Crested Lark, Red-vented Bulbul, Graceful Warbler and House Sparrow. A combination of municipal horticulturalists and picnickers certainly deterred Great Grey Shrike from nesting, and to date no evidence of breeding has been noted within the formal man-made boundaries. It does however breed in Acacia scrub within 2 km of the park.
The park serves as a giant larder to a number of species, and observations show that those residents which do not nest inside the park certainly feed there outside the breeding season. This is particularly true of Great Grey Shrike. Therefore Saffa Park was an ideal site to measure the non-breeding movements of the species. Table 1 shows the number of birds observed on visits to the park, maximum recorded in each 10 day period. The visits were of approximately one hour in length normally every 2-3 days, and the maximum observed. in one hour is entered on the table.
Table One: Occurrence of Great Grey Shrike (Lanius excubitor) in Saffa Park, Dubai, 1984-88 (Man. observed per day/third of a month)
Taking these figures it was possible to display them graphically using a stacked bar chart. This method exaggerates the real occurrence, but more clearly indicates the peaks and troughs of passage, dispersal and breeding season.
1. There is a distinct absence of birds from January to late April. This concurs with our knowledge of the Great Grey Shrike's nesting season, when the adults rarely stray far from the nest site. It suggests that few nesting birds entered the park during this time.
2. It indicates irregular March passage in the UAE (or at least Saffa Park). There was some influx in mid-March 1986 and 1987, which were probably migrants. Field notes taken of the birds observed in mid-March 1987 refer to different field characteristics from the known resident sub-species.
3. There is a definite return of residents and their fledged young to the park from May to July. A further increase in numbers in August and September is an indication of significant passage. Birds of other races were noted at this time, and on several occasions three or more birds were recorded in the small confines of the park between August and October. Passage is shown to end by mid-November, and in December only one or two birds were present, probably pairing residents.Summary
The statistics confirm it to be a common resident and regular autumn passage migrant August to mid-November, with a lighter spring passage March to mid-April (though late spring passage records may be confused with an increase in locally fledged birds). There is no evidence of birds wintering in Saffa Park (i.e. November to February) and observations elsewhere in the Dubai area do not back up reports of this species wintering in the area.
There is clearly much scope for further studies of passage timings and occurrences of the various sub-species of Great Grey Shrike in the UAE and it is hoped that future observers will add to our steadily increasing knowledge of the region's birdlife.
NOTE: Following publication of Birds of the Middle East and North Africa by Hollom, Porter et al in 1988, our knowledge of the field characteristics of occurring sub-species has increased. As a result, a number of birds observed in March 1989 were identified as belonging to the race L. e. pallidirostris, lending further weight to the evidence of March passage of this sub-species.Bibliography
Colin Richardson: John R.Harris & Partners, P.O.Box 2825, Dubai, UAE.
Patron: H.E. Sheikh Nahayan bin Mubarak Al Nahayan
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