Dr Johannes Kamp, who has been involved in working on Sociable Lapwings for many years, talks us through the findings on winter habitat use…
When we initially started to track Sociable Lapwings back in 2007, we were mainly interested to learn more about their migration routes and exact wintering areas. Within a few years, we succeeded in identifing the most important stopover sites along the two flyways to the wintering areas in Sudan and India and tackle threats at these sites together with conservation organisations on the ground.
Since 2011, we have used new lightweight 5-g satellite tags and a newly designed harness to attach the tags. This has massively improved the number and accuracy of coordinates we receive from our birds. There are now plenty of coordinates transmitted up to twice a week. This gives us the great opportunity to follow our birds within their wintering areas, and we use satellite aerial images to see which habitats they favour. This is important, as little was known about winter habitat use in this species before the Sociable Lapwing project was initiated, and the African wintering areas are extremely remote places rarely visited by local ornithologists.
Sociable Lapwings are quite gregarious during the winter (hence their Latin name Vanellus gregarius): Shirin and Boris, the two tagged birds wintering in Sudan, settled in an area of Savannah and grazed land used by local nomadic tribes in November 2014, but moved over 200 km SW in early 2015 to an area of arable fields. Ibrahim Hashim from the Sudanese Wildlife Society (who found satellite tagged birds on the ground in his country) suggests that the birds abandon the grazed savannah as it becomes more and more overgrazed later in the season, and turn to fields which supply more insect food.
In contrast, Irina in Saudi Arabia was rather immobile: she has been using irrigated pivot fields in a narrow radius during the entire winter, a relatively new habitat known to serve as stopover and wintering site for a number of birds in the hostile Arabian Desert. Interestingly, Boris stopped over in autumn at these fields as well, but decided then to move on to Africa.
In India, Hanna relied entirely on small-scale farmland, and travelled around in a manner similar to the birds in Sudan.
The Sociable Lapwing is an example of a ‘synanthropic’ species, following closely humans and their activities. The preferred habitats of the species – grazed pasture and arable fields used with low intensity – are very similar during the breeding, migration and wintering seasons: the species is clearly ‘tracking’ its ecological niche during the yearly cycle. However, this means also that the species is extremely vulnerable to changes in livestock grazing and agricultural intensification – land-use changes on the wintering grounds need to be monitored closely.
[Header photograph: Ibrahim Hashim]