He’s done it! It is just 11 days since AW left his nest close to Rutland Water, but he has already crossed the Sahara and reached Senegal. At 9pm last night he was in Reserve de Faune du Ferlo-Nord an extremely remote part of central Senegal, 112 miles miles west of the town of Touba.
The previous batch of data had shown that AW was in southern Mauritania at 5pm on Tuesday evening and the latest GPS fixes show that he continued heading south for another 54 kilometres before eventually settling to roost 15km north of Lake Aleg, before 7pm. He was now just 82 kilometres from the Senegal border. According to the Birdlife website “Lake Aleg is a closed depression in an old course of the Senegal river fed by rainwater run-off. The lake is endorheic and semi-permanent and typically varies in depth from 1–2 m at the end of the dry season to a maximum of 3–4 m at the end of the rains.” In winter it is home to more than 50,000 Garganey, who like AW will cross the Sahara from northern Europe. Despite being so close to the most significant piece of water he would have seen for days, the satellite data suggests that AW did not fish in the lake that evening. Perhaps he was just too tired? In fact he was now starting to show some signs of fatigue – his day’s flight of 330km was 100km less than the distance he covered during the previous two days. He had every reason to be tired – he had now crossed the Sahara and had covered an incredible 2400km since Saturday morning.
Next morning AW was migrating again by 9am, heading south east at 27kph. Like the previous evening there is no data to suggest that he visited the lake to go fishing, but the gap in data means that we can’t rule it out. AW made steady progress south east during the morning and by midday he had covered 90km. At this point he made a very obvious change of direction – shifting his course to south west.
At 2pm he was flying over the Senegal River, but once again the data suggested that he didn’t stop to fish. He was flying at an altitude of 260m and an hour later was another 28km further on.
He covered another 50km on the same south-westerly course but at 5pm changed direction again, this time heading south east. By 9pm he was at roost 40km further on having completed a day’s flight of 269km. This final change of direction is very interesting and suggests that rather than heading to Gambia and Senegal, AW may be on his way further south – perhaps to Guinea-Bissau? Although he made a couple of deviations during the day, his roost site was almost due south of his position the previous night.
Irrespective of exactly where his wintering site is, if he continues at his current rate, the chances are that AW will be there by Saturday. If this is the case he will have reached his winter home in just two weeks. Truly remarkable!