Since 2006, we have conducted conservation-focused research on the breeding ecology of Pallid and Montagu's harriers in central Asia in cooperation with the Naurzum Nature Reserve (North-central Kazakhstan) and the National Aviary of Pittsburgh (USA). Click here to navigate to our project page.
The Pallid Harrier (Circus macrourus) is a migratory raptor that breeds from the Volga River eastwards through the Urals, southern Siberia, northern Kazakhstan and north-western China. Its main population strongholds are in southern-asian Russia and northern Kazakhstan, which host c. 87 % of the world population. The population has declined in recent decades mainly on its western range distribution limits. Local declines have also been reported in Central Asia. The Pallid Harrier is classified by IUCN as a Near Threatened species.
Declines have been mainly attributed to breeding habitat degradation, leading to degradation of nesting habitat and reduction in prey availability, but migratory birds are also very sensitive to wintering conditions and it is known that the loss of high-quality wintering areas can influence breeding success during the following season. Wintering distribution of this species and the connectivity between breeding and wintering subpopulations is poorly known. Land-use transformations have also resulted in large-scale loss of dry grasslands and savannahs in Central Africa and India, the main wintering areas of this species. This project will identify the links between breeding and wintering populations, with the use of long-lived satellite-transmitters, and determine if the population dynamics of this species is affected by winter conditions.
Pallid Harrier with satellite tag
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In 2007, as a consequence of a low vole abundance year, breeding density of pallid harriers in the study area was very low ( only 4 breeding pairs), and we could only fit one female with a satellite-transmitter. However, in 2008, harrier breeding densities were much higher (in response to a good vole year) and we were able to fit 8 more harriers with satellite tags.
We lost the signal of two birds prior to their migration. A total of 6 birds began their migration trip in September 2008. They all followed the same route from their breeding grounds in northern Kazakhstan to the eastern coast of the Caspian Sea in Russia, through Georgia, Turkey, Iraq, Saudi Arabia, and then crossed the Red Sea (2 of them passed by Egypt, see map below).
 The blue line is the spring migration route of the Pallid Harrier we tracked from its wintering grounds in India (click here to find out more about this bird). The other colours represent the autumn southern migration routes (from Kazakhstan to Africa) of the other 6 Pallid Harriers.
After arriving in Africa in early October 2008, the birds chose several different wintering areas. Two birds went to Ethiopia (where we lost the signal of one of them), two birds went to Sudan, including the female we captured in 2007, who also over-wintered in Sudan last year (we have since lost transmission with one of the birds in November 2008) and interestingly, two birds took a more westerly route and spent the winter in Niger.
In mid-March 2009, two birds began their return trip north to their breeding grounds in Kazakhstan and one bird is now in Libya and another in Saudi Arabia.
This project forms part of Julien Terraube's PhD studies and is supervised by Mike Madders, Bea Arroyo and Francois Mougeot.
Maps copyright: F. Mougeot
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