Going back in time – VY’s travel on 9 and 10 September – and a bit more

The missing data for 9 and 10 September arrived yesterday. 9 September was VY’s longest active day and furthest travelling distance by far: – she flew 523 km at an average speed of 40 kph in twelve hours. This is her route.

9 Sept: VY's route

9 Sept: VY’s route

At around 13.00 UTC VY was flying east of the Barrage al Massira which is on the Oum Er Rbia, where cousin 7H has her wintering home at the coast. She curved to a more WSW direction as she rounded Marrakesh shortly before 16.00. In this period she was around 1500m above the terrain and she was using updrafts as shown in the image in the previous post to gain height and speed. It looked likely that VY would meet the sea north of Agadir then take a coastal route but at  19.15, when she was about 65 km from the sea, she changed course to fly parallel to the coastline.

She didn’t stop until about 20.40 when she found a roost on the desert floor.

9 Sept: 7H's roost

9 Sept: 7H’s roost

Despite her long day VY didn’t have a late start on 10 September, setting off at 08.36. She continued parallel to the coast and was only about 40 km away when north of Guelmin around 14.00. But then she changed to a more southerly route as can be seen in the image of her day in the Atlas Mountains.

10 Sept: VY's route

10 Sept: VY’s route

VY stopped to roost (image in previous post) just after 17.00, having covered 305 km at an average speed of 36 kph.

Her journey through the Sahara featured in the previous post, but a few more details follow. She crossed into Western Sahara then Mauritania during 11 September, when she travelled 335 km at an average speed of 36.6 kph. She flew for just over 9 hours on both 11 and 12 September. On 12 September she was slightly faster – 38.1 kph – and added 345 km to her distance total.

Each day in the desert she would be flying at over 1000m above the terrain at times, and as high as 1800m, even when it was not high ground beneath her. On 13 September she passed an interesting feature in the Akchar Desert, the Richat Structure.

VY has a good view of the Richat Structure

VY has a good view of the Richat Structure

For those not clicking on the link it was once thought to be the result of an asteroid impact, but now is thought to be a geological dome with spectacular hydrothermal features. VY was well over 1000m above the surrounding terrain at the time she passed, so a real bird’s eye view!

On 13 September VY flew 358 km in 8.41 hrs at an average 41.2 kph. Most of her desert roosts were in fairly featureless terrain, but 13 September was a more interesting spot.

13 Sept: VY's roost

13 Sept: VY’s roost

You can see signs of water in the Google Earth imagery – there is an oasis nearby. But VY didn’t linger and was flying away by 08.55.

On 14 September she was over relatively low terrain but maintained her high flying most of the day, when she covered 337 km at an average speed of 39.2 kph.

On 15 September she reached Senegal. Paul’s graphic in the last post showed VY’s thermal soaring as she approached the Senegal River. One of the features she passed was Lake Aleg; she dropped altitude and had a look.

!5 Sept: VY over Lake Aleg

!5 Sept: VY over Lake Aleg

Why didn’t she stop? The water at the moment doesn’t look quite as inviting as this weather image from Paul shows.

!5 Sept: the Senegal River and surrounding area

15 Sept: the Senegal River and surrounding area

‘A’ is the very silty looking lake, ‘B’ the valleys that feed into it. They are green, not dry as on the Google Earth image. ‘X’ is VY’s roost position. And ‘C’ shows the silt outflow at the Langue de Barbarie, much reduced in size but still visible. This graphic may feature again in an upcoming blog on UV and 7H – they are both fine.

Paul has prepared statistics for VY from leaving Kielder to her roost on 15 September.

Kielder to Senegal

Kielder to Senegal

Below is an image of her path.

VY to 15 September

VY to 15 September

Yesterday there was only one fix of VY setting out from the roost area.

16 Sept: VY flies away from her roost

16 Sept: VY flies away from her roost

It isn’t possible to deduce anything from such limited data, but she should be within range of cell towers for a data download today. She could have flown some distance as the expected rain still hasn’t arrived. The winds have been westerly but are likely to change to a more northerly direction this afternoon.

We wish VY a safe onward journey.

 

This entry was posted in Abroad, Blue VY, Migration, Osprey updates and tagged , . Bookmark the permalink.

One Response to Going back in time – VY’s travel on 9 and 10 September – and a bit more

  1. Cirrus says:

    I just wish they wouldn’t roost on the desert floor! (I appreciate they often don’t have any choice but, it’s such a worry !!)

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