He’s made it. Last night Blue DF roosted 40 km to the east of Louga in northern Sengeal having completed his crossing of the Sahara in four days.

On Thursday night last week (21 September) Blue DF has roosted close to the Morocco-Western Sahara border in the Sahara and he left his roost at 09:20. Conditions were obviously perfect for migration because four hours after leaving his overnight roost he had already flown 197 km and crossed into Mauritania. He continued to make excellent progress during the afternoon, flying at altitudes of up to 1174 m, and by the time he stopped to roost at 18:49 he had flown 503 km on a constant south-westerly heading.

Blue DF’s was flying through Western Sahara on 21st September

Next morning Blue DF left his overnight roost in the desert fairly early, at 08:25. Like the previous day, conditions must have been in his favour because he made good progress, passing to the east of the vast Fderik iron ore mine at 11:02 and then onwards through the Akchar desert at altitudes of up to 1170 m. He continued flying until 19:20 when he finally settled to roost among sparse vegetation having flown a further 432 km through the desert.

Blue DF passed the vast Fderik iron ore mine on Friday morning (22nd Sept)

On Saturday morning Blue DF left his overnight roost just before 9:30, again on on a south-westerly heading. He made slower progress than the previous two days and by 14:11, when he was migrating at an altitude of 1500 m, he had flown 124 km. He eventually settled to roost for the evening at 18:30 having flown 252 km during the course of the day and was now just 80 km east of the Mauritanian capital, Nouakchott and nearing the end of his desert crossing.

Blue DF’s roost in the Sahara on Saturday evening

Blue DF must have sensed that he was close to completing his crossing of the Sahara because he left his roost early at 08:16. He appeared to be heading towards the coast, but at 10:22 he turned to a southerly heading for the next four hours, crossing the Senegal River at Richard Toll at 14:15 – his first sight of water for at least four days – before continuing south along the east shore of Lac de Guiers during the course of the afternoon. By 16:29 he was at the southern end of the vast lake, but it seems that he did not stop to catch a fish, and instead continued another 34 km south-west before settling to roost 20 km east of Louga in the arid north of Senegal.

Blue DF crossed the Senegal River on Sunday and then continued south along the east shore of Lac de Guiers

With the desert crossing behind him it will be fascinating to see where Blue DF migrates to. As an adult osprey he will have a regular wintering site in West Africa, but the question is where? On his current course he may be heading for the Sine-Saloum delta in Senegal, or he could head further south to The Gambia, the Casamance region of southern Senegal, or perhaps, Guinea-Bissau. Watch this space! In the meantime, you can check out his migration so far on our interactive map.

Blue DF flew 1500 km across the Sahara in four days between 21 and 24 September

After arriving in Africa on Sunday evening Blue DF has flown the length of Morocco over the past three days and at 11:09 this morning was heading south through Western Sahara.

The previous data had shown that at 11:13 on Monday morning Blue DF was at Barrage Oued El Makhazine in northern Morocco. It is possible he caught a fish because he was then perched 8 km to the south for almost an hour. Once he resumed his migration he made good progress on a  constant south-westerly heading at altitudes of up to 1350 m. At 19:41 local time he arrived at another reservoir, Barrage Al Massira having flown 307 km since 12:45. He arrived at sunset and so it is unlikely that he caught a fish; instead he settled to roost 9 km south-west of the reservoir after a day’s flight of 380 km.

Blue DF roosted to the south of Barrage Al Massira on Monday evening, with the Atlas Mountains in the distance

By dawn next morning Blue DF had moved location several times during the night and was 56 km further south-west. He continued to make stuttering progress during the morning and at 12:10 and 12:34 he was perched beside another reservoir, 60 km north-west of Marrakesh, perhaps eating a fish. By 12:59 he was migrating again and he flew strongly south-west during the course of the afternoon, pausing briefly at Barrage Prince Moulay Abdellah and then continuing onward towards Agadir. At 17:01 reached the coast and headed south-south-east for 60 km over the sea at altitudes of between 150 and 170 m, perhaps to avoid the city. He reached land again at 18:13 and eventually settled to roost half an hour later, 58 km south of Agadir after a day’s flight of 328 km.

Blue DF flew 60 km over the sea rather than keeping to the coast over Agadir

After a slow start on Wednesday morning, when he may have caught a fish in the Massa River, Blue DF set-off again soon after 11:00, passing just to the west of Tiznit at 12:00 and then out into the Sahara, flying over some spectacular landforms in the process. By 17:11 he had flown 197 km and was migrating at an altitude of 1179 m and approaching the spectacular ridge that runs for 350 south-west across the northern edge of the desert. Many ospreys follow this ridge on their migration by Blue DF crossed it and then maintained the same southerly heading for a further 67 km before settling to roost on the desert floor on the Morocco-Western Sahara border just before 19:00. He had covered a total of 264 km during his day’s flight.

Blue DF flew over some incredible landforms as he headed into the Sahara

By 09:32 (local time) this morning Blue DF had moved 3 km to the south-west and he resume his migration soon after 10:00. At 11:09 the last GPS fix in this batch of data he was 29 km further on migrating south-south-west at an altitude of 857 m, with the vast expanse of the Sahara ahead.

Blue DF crossed Morocco in three days and is now flying south through Western

Don’t forget that you can also check out Blue DF’s migration on our interactive map.

After a relatively slow start to his migration Blue DF really increased his pace over the weekend, flying the length of Spain in just over two days and crossing the Strait of Gibraltar to Africa yesterday evening. The latest data shows that at 11:13 local time this morning he was at Barrage Oued El Makhazine in northern Morocco.

In our previous update on Friday evening Blue DF was flying south through northern Spain and we now know that he continued flying until around 20:30 loal time, when he was perched beside the Rio Duero having flown 315 km from north of Biarritz.

Blue DF spent Friday evening perched beside the Rio Duero, 130 km north-east of Madrid

On Saturday morning he left his roost site at 08:15 local time but then spent an hour-and-a-half perched another 8km further south. By 10:50 he had resumed his migration and was soon flying through mountains to the north of Madrid, climbing to over 2000 m in the process. He then skirted around the west side of the Spanish capital before continuing on a south-westerly course through eastern Extremadura towards the Sierra Morena mountains.  At 16:42 he was at an altitude of 2879 metres and would have had a good view south towards Embalse de Cijara. He was flying low over the reservoir half an hour later and then perched at the water’s edge for the next hour-an-a-half, presumably eating a fish. At 18:44 he was migrating again and he continued flying until after 20:00, covering another 71 km in the process. By the time he settled to roost in the Extremadura plains he had flown 364 km during the course of the day.

Blue DF skirted around the western side of Madrid on Saturday

The satellite data suggests Blue DF caught a fish at the EMbalse de Cijan in Extremadura on Saturday afternoon

On Sunday morning Blue DF made a fairly slow start to migration, finally leaving his overnight roost at 10:30. At 13:10 he had reached the northern edge of the Sierra Morena and he continued south across the mountains before pausing beside the Rio Guadalquivir for almost two hours during mid-afternoon; perhaps to eat a fish. By 17:11 he was heading south again and at 17:59 was passing to the east of Seville at an altitude of 850 m. Conditions must have been very good for migration because he showed no sign of letting up, continuing south through Andalucia. By 22:06 he was over Algeciras and, even though it was now an hour-and-a-half after sunset, he headed due south across the Strait of Gibraltar, making landfall near Eddalya at 22:55 Spanish time after a 17 km crossing.

At 22:06 on Sunday evening Blue DF set out across the Strait of Gibraltar in darkness towards Morocco

Despite reaching Moroccan airspace in the dark Blue DF continued flying for another 55 km before eventually settling to roost on a forested hillside after a day’s flight of 389 km.

This morning Blue DF had already left his overnight roosting site at 06:48 local time, but he then stopped again 11 km to the south. He resumed migration just before 10:00 and by 11:13 he was heading south over Barrage Oued El Makhazine reservoir having covered 64 km.

Blue DF’s flight 15-18 Sept

Don’t forget that you can check out Blue DF’s migration on our interactive map.

After a slow but steady flight through France, Blue DF has quickened his pace considerably in the last 48 hours and at 18:40 this evening he was flying south through the Castile and León region of north-east Spain.

In Wednesday’s update we reported that Blue DF was approaching the Atlantic coast of France, but the weather was clearly poor for migration because by 17:15 when he stopped at a series of small lakes near the village of Chevallon he had only flown 133 km during the course of the day, with several stops en route, perhaps during heavy rain showers. At 18:28 he was fishing in the lake, and then spent the rest of the evening perched in lakeside trees, presumably eating his catch. He eventually flew off to roost in a wooded area 1.5 km south.

Blue DF spent all of Wednesday afternoon beside a series of lake near the village of Chevallon in western France before roosting nearby.

Next morning he was back at the lakes at first light, and didn’t resume his migration until just before 11:00 local time. At 13:45 he flew low over the Girone estuary at an altitude of 72 m, before passing to the west of Bordeaux and then east of Arcachron Bay at a higher altitude of 450 m. At 18:10 he arrived at Etang de Soustons, a lake 35 km  north of Biarritz, and spent half and hour fishing in the lake. He then flew to a wooded area to the west and remained there for the rest of the evening having covered 239 km during his day’s flight.

Blue DF roosted in a wooded area to the west of Etang de Soustons in south-west France on Thursday night.

Blue DF was back at the lake at 09:44 and then spent an hour perched 3 km to the south, perhaps eating a fish. By 11:21 he was migrating again and over the course of the next few hours made good progress south, passing 13 km to the east of Biarritz at 13:23 and then crossing into Spanish airspace at an altitude of over 1105 m at 15:23. An hour later he passed over Pamplona and by 18:40, the last GPS fix in this batch, he had flown 237 km and was still heading powerfully south-west towards central Spain.

Blue DF was flying south through northern Spain this evening.

Don’t forget that you can also check out Blue DF’s migration on our interactive map.

Over the last two days Blue DF has made fairly slow progress through France and at 11:14 this morning was approaching the Atlantic coast, 80 km east-north-east of La Rochelle. You can check out his latest location on our interactive map.

The last GPS fix in the previous update, at 10:37 on Monday morning, showed that Blue DF was heading south through Lower Normandy. That afternoon he continued flying until 14:17 when he was perched beside Étang du Lory, a small lake in a forested area north of Tours. He remained there all afternoon – and presumably caught a fish – after a day’s flight of 120 km.

Blue DF spent much of Monday afternoon beside Étang du Lory and then next morning was perched beside nearby Étang du Petit Puis.

After roosting away from the lake, Blue DF was back at nearby Étang du Petit Puis at first light next morning, indicating that he may have caught a fish before resuming his migration. He set-off again soon after 08:00, passing to the west of Tours and then stopping again for three hours beside the River Vienne near the village of Rivière; so if he didn’t catch a fish earlier in the morning, he definitely did then. The weather was clearly poor for migration because having resumed his journey soon at 14:00 Blue DF only covered another 25 km south before stopping again at another small lake. He remained there for an hour before flying 2km south-west to a forested area to the west of the village of Bethergon where he remained to roost after a day’s flight of just 87 km.

Blue DF stopped beside the River Vienne for three hours on Tuesday – suggesting he probably caught a fish there.

This morning Blue DF was obviously eager to press on because he left his overnight roost soon after first light, on a a south-westerly heading. A strong strong south-westerly wind would have made for fairly tough going, but at 11:14, the last GPS fix in this batch of data, he had covered 70 km, heading towards the coast north of Bordeaux.

Blue DF was approaching the Atlantic coast of France this morning

Finally, thank you very much to Val Gall for sending this superb photo that she took of Blue DF earlier this summer. Our thanks to Julian Orsi and Rothiemurchus Estate for allowing us to catch and tag Blue DF at Rothiemurchus last week.

Blue DF at Rothiemurchus Fishery earlier this summer (photo by Val Gall)

Over the past twenty years Roy Dennis has pioneered the use of satellite transmitters to follow UK ospreys on migration and to learn more about their movements on both the breeding and wintering grounds. Much of this data is in included in my recently completed PhD thesis. This autumn we are tracking a new adult male osprey on migration, Blue DF. This osprey is well known to wildlife photographers because it regularly fishes at both Rothiemurchus Fishery and also Aviemore Lochan – a quick Google search will reveal an array of stunning photos of the bird. He was originally ringed as a chick at nest A18 by Roy Dennis in 2010 and this spring took over from another well-known osprey, Red 8T, at nest A10 in Strathspey. He successfully reared two chicks with an unringed female and by Wednesday evening last week, when we caught him under licence at Rothiemurchus Fishery, his family were already heading south. Blue DF was also ready for migration: he weighed over 2kg having put on around 500g of fat in preparation for his long journey south.

Blue DF is regularly seen fishing at both Rothiemurchus Fishery and Aviemore Lochan (photo by Mike Crutch)

Sure enough when we received the first data from his transmitter at 11:30am on Friday morning he was already in the Scottish borders, 10 km south-east of Kelso. Over the course of the next five hours he made steady progress south-east and at 16:40 he was just east of York at an altitude of 668 metres. An hour later he passed to the west of the Humber estuary and he finally settled to roost for the night in the corner of a deciduous woodland 15 km north-west of Lincoln.

At 09:54 next morning Blue DF had flown over the western part of Lincoln and was migrating south-east, in a strong westerly wind. Three hours later, despite heavy squally showers, he had flown 96 kilomteres from his overnight roost and was heading over Peterborough at an altitude of 682 metres. He maintained a constant south-easterly course through Cambridgeshire and then Essex, crossing the Isle of Sheppey soon after 16:00. He eventually settled to roost for the night in a wood midway between Tunbridge Wells and Folkestone in southern Kent after a day’s flight of 282 km.

Sunday morning dawned sunny and clear on the south coast and DF was obviously keen to press on because at 06:12 he was already 20 km south of Hastings, crossing the English Channel at an altitude of 124 metres. The 117 km crossing took three-and-a-half hours with Blue DF making landfall to the west of Dieppe soon after 09:00. He then continued on a southerly heading through Upper Normandy, at a relatively low altitude (maximum 392 metres) before settling to roost in a forested area near the village of La Saucelle, some 100 km west of Paris after a day’s flight of 277 km.

Blue DF made a 3.5 hour, 117 km crossing of the English Channel between Hastings and Dieppe on Sunday morning. Times and altitude above sea level shown on map

The satellite data suggested that DF hadn’t fed since leaving Scotland but at 09:01 this morning he was fishing in small lake 31 km south-west of his overnight roost. He was obviously successful because the next two GPS fixes (separated by 30 minutes) show he was perched nearby, presumably tucking into breakfast. He didn’t linger for long however because at 10:39, the last GPS fix of this batch, he was 12 km to the south-west migrating onwards at an altitude of 311 metres.  We’ll update you on his progress later in the week. You can also check out Blue DF’s migration on our interactive map. It will be fascinating to see where this experienced adult osprey spends the winter.

Blue DF stopped to fish at a series of small lakes near the town of Nogent-le-Rotrou on Monday morning

Blue DF’s migration from Strathspey to Lower Normandy, 7-11 September