Senegal
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A multiple exposure of three photos shows the flurry of activity in a pre-roost gathering of Montagu's harriers. Khelcom, Senegal.
Every year, thousands of wildfires burn across the arid grasslands of the Sahel. Some fires are ignited by lightning strikes, but they are also actively used to convert land for agriculture. Here, a wildfire stretching several kilometers rushes across grassland near Khelcom, Senegal, driven by strong wind.
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Agriculture is intensifying throughout the Sahel. Insect and songbird populations drop as a result of the loss of trees and shrubs to arable land. This has a particularly negative effect on the Montagu's Harrier, which relies on these animals for food. Kaolack, Senegal.
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Excited expressions appear on researchers' faces when the first GPS tracks of a Montagu's harrier's daily movements appear on screen. Khelcom, Senegal.
Using a system of relay antennas strategically positioned around several roosts near Khelcom, Senegal, researchers can read out the birds' data loggers. This yields detailed information on birds' movements (e.g. location, elevation, flight speed, and temperature in three-second intervals), but also migratory data for birds that have been equipped with GPS-loggers at European breeding sites in previous years.
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Khelcom, Senegal
Montagu's harriers spend six months of the year in the Sahel. This female forages by a lone baobab tree. Khelcom, Senegal.
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A female Montagu's harrier is fitted with a GPS-backpack in Khelcom, Senegal.
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Steve Augiron hoists a solar panel up a water tower to power a base station that can communicate with relay antennas strategically placed in the the field. The base station takes care of two-way communication with GPS-loggers in the system's range, and transmits data to a cloud database over the cellular network. This allows for the collection of information on birds' movements at very short intervals, which the GPS-backpacks' internal memory cannot store for more than a few days.
A wildfire rages into the night, silhouetting a nearby settlement. Khelcom, Senegal.
Using a system of relay antennas strategically positioned around several roosts near Khelcom, Senegal, researchers can read out the birds' data loggers. This yields detailed information on birds' movements (e.g. location, elevation, flight speed, and temperature in three-second intervals), but also migratory data for birds that have been equipped with GPS-loggers at European breeding sites in previous years.
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Khelcom, Senegal
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Almut Schlaich and Ben Koks fit a male harrier with a GPS-backpack on the savannah of Khelcom, Senegal.
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Almut Schlaich climbs a water tower to setup a base station that can communicate with relay antennas strategically placed in the field. The base station takes care of two-way communication with GPS-loggers in the system's range, and transmits data to a cloud database over the cellular network. This allows for the collection of information on birds' movements at very short intervals, which the GPS-backpacks' internal memory cannot store for more than a few days.
Scientists Steve Augiron (France) and Almut Schlaich (Germany) set a mist net to capture Montagu's harriers in order to fit them with GPS-loggers. The harriers are enticed to dive at it by placing a large model owl behind the net (photos of harriers diving at owl available). Khelcom, Senegal.
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A live grasshopper next to Montagu's harrier pellets in the hands of Ben Koks. Fatick, Senegal.
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Well over a thousand Montagu's harriers gather at one of the largest roosts ever recorded. Roosts typically don't exceed 200 birds and many are much smaller still. Khelcom, Senegal.
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A male Montagu's harrier is carefully fitted with a GPS-backpack in Khelcom, Senegal.
Steve Augiron untangles a male Montagu's harrier from a mist net as Ben Koks (Netherlands) watches. Khelcom, Senegal.
In the Sahel, insects like grasshoppers form the chief source of food for Montagu's harriers, whereas in Europe they feed mostly on small mammals and birds.
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Millions of grasshoppers are driven together in an ever darkening cloud as fire rushes across the grassland. Khelcom, Senegal.
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A Peul (also known as Fula) sheppard grazes his herd near Khelcom, Senegal. Some conservationists fear that the Islamic marabout who have obtained the political power in this region use fires to drive out the Peul, who traditionally graze their cattle on these lands.
A village chief accepts a T-shirt sporting a Montagu's harrier. Without the approval of local communities it would not be possible to carry out research in this region. Khelcom, Senegal.
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