Male Montagu’s Harrier Edwin, named after Uva-BiTS engineer and co-developer Edwin Baaij, was one of the first harriers fitted with an UvA-BiTS GPS tracker in Eastern Groningen in 2009. Because our team at the Dutch Montagu’s Harriers foundation (Stichting Grauwe Kiekendief) knew which areas he had been inhabiting during previous winters, Edwin was the target bird of our first trial to find a bird in its wintering area in Africa.In mid-February, I (Almut Schlaich) made my way to Senegal together with two French colleagues to find Edwin. Our goal was to find him, download the data collected since summer 2012 and upload a new measurement scheme for the rest of the winter and the coming spring migration. In addition, we would collect field data in the wintering area where he spends more time each year than in his summer breeding area. Because Montagu’s Harriers are very site-faithful in winter, we knew that if Edwin was still alive he would be in an area close to Fatick, Senegal. So that was where we went!

Montagu’s Harriers roost communally. Therefore, our first step was to find roosts and set up the antenna during the evening. While observing the second roost we couldn’t believe our eyes. Among a group of about 70 other Montagu’s and 5 Marsh Harriers, suddenly Edwin passed our observation point within about 30 meters distance! We could almost see the mounted GPS tracker without binoculars. At that point, no contact was established with the tracker, despite the fact that the mobile base station was up and running. The same happened the following evening, when we saw Edwin again but no contact with the tracker was made, and we started to fear that the GPS tracker was not working anymore. On the second day we managed to find Edwin during the day, while he was foraging. By following him over open dried-out lakes and through bushes we finally made contact with the tracker. The download started and while Edwin was catching some grasshoppers, valuable data was streaming in. Just before midday, when it heats up in Senegal, Edwin moved. We followed him and saw that he landed in a tree. At about 100 meters distance from the tree we stopped and waited about 2.5 hours in a very hot car (without food!) until all data recorded from June 2012 until that day was downloaded. How glad we were! Without disturbing the bird we left Edwin and had a well-earned lunch in the shade.

During the following week we managed to find him three more times and download the data that was collected in the meantime. When we left Edwin we knew much more about him, the same bird we normally see dancing above the fields in Eastern Groningen. In Senegal, he has a quiet life without a female or chicks to care for. Eating some grasshoppers in the morning and afternoon is nearly all he does. During the hot hours he sits in the shade in a tree or under a bush. And in the evening he returns to his roost to meet the other birds. Not very exciting but very safe for sure! That gives us hope that we will see Edwin back in the Netherlands in a few weeks for a new breeding season.

For more on this project being conducted by the Dutch Montagu’s Harriers foundation and the University of Amsterdam, see Conservation of Montagu’s Harrier.