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Aim To identify the migration routes and wintering grounds of the core populations of the near-threatened pallid harrier, Circus macrourus, and highlight conservation needs associated with these phases of the annual cycle. Location Breeding area: north-central Kazakhstan; Wintering areas: Sahel belt (Burkina Faso to Ethiopia) and north-west India. Methods We used ring recovery data from Kazakhstan and satellite tracking data from 2007 to 2008 on six adults breeding in north-central Kazakhstan to determine migration routes and locate wintering areas. In addition, one first-year male was tagged in winter 2007-2008 in India. Results Data evidenced an intercontinental migratory divide within the core pallid harrier population, with birds wintering in either Africa or India. The six individuals tagged in north-central Kazakhstan followed a similar route (west of the Caspian Sea and Middle East) towards east Africa, before spreading along the Sahel belt to winter either in Sudan, Ethiopia, Niger or Burkina Faso. Spring migration followed a shorter, more direct route, with marked interindividual variation. The bird tagged in India spent the summer in central Kazakhstan. Half of the signal losses (either because of failure or bird mortality) occurred on the wintering areas and during migration. Main conclusions Our study shows that birds from one breeding area may winter over a strikingly broad range within and across continents. The intercontinental migratory divide of pallid harriers suggests the coexistence of distinct migratory strategies within the core breeding population, a characteristic most likely shared by a number of threatened species in central Asia. Conservation strategies for species like the pallid harrier, therefore, require considering very large spatial scales with possibly area-specific conservation issues. We highlight urgent research priorities to effectively inform the conservation of these species. [ABSTRACT FROM AUTHOR]

The ecology and conservation status of Central Asian populations of Montagu’s Harriers Circus pygargus are poorly known. We studied the breeding biology of this species during 3 years in the Naurzum region, north-central Kazakhstan. Most Montagu’s Harriers in the study area nested in the forest-steppe transition area, in bushy areas dominated by dogrose Rosa canina, which was apparently the nesting vegetation type providing highest and densest nest cover in the study area. Laying occurred from 26 April to 7 June (average 13 May, n = 49) and, although it varied significantly between years, was earlier than in western European populations of similar latitude. Mean (±SD) clutch size was 4.44 ± 0.86 (range 2–6; n = 50), in the higher range observed for the species. There was no significant interannual variation in clutch size, despite large variations in the abundance of small mammals in the area. Diet was mainly composed of lizards (54.2%, n = 533 identified prey in all 3 years), with small mammals (17.1%), passerine birds (14.3%) and insects (13.6%) also being consumed. Mean brood size at the last visit was 2.55 ± 2.10 (range 0–6; n = 51). Failure rate was relatively high; the main identified cause of nest failure was predation. We compare the data obtained in this population breeding in natural steppes with breeding parameters from the well-studied western European populations, and discuss the implications for the conservation of this species. [ABSTRACT FROM AUTHOR]

We studied a breeding population of pallid harrier Circus macrourus in 2000 and 2006 in north-central Kazakhstan to evaluate the relationships between breeding parameters and breeding habitat in the species' core breeding range. Pallid harrier nests were found in a wide variety of vegetation types and heights belonging to three main types: steppe, riverine and agricultural. The proportion of nests found in each habitat type (corrected for search effort) differed between 2000 and 2006, with agricultural habitats being more used in 2000, when fallow land was abundant, than in 2006. Highest densities were observed in riverine habitats but hatching success seemed to be lower there because of greater predation. There was apparently lower productivity (smaller broods) in agricultural than in other areas. Laying was spread over 2 months, with a bimodal pattern of laying dates. Birds laid earlier in agricultural and steppe habitats and later in riverine habitats. These differences may be linked to spatio-temporal habitat heterogeneity, and possibly to intra-population heterogeneity in wintering areas implying different arrival dates on the breeding grounds. We discuss the implications of the findings for the conservation of this Near Threatened species. [ABSTRACT FROM AUTHOR]