The Flight of Osprey S06

This Osprey is a breeding female - ten years old. BTO Ring number 1306910. Green colour ring, with white letter J on left leg.
Caught on Strathspey Estates, near Boat of Garten, 17th July 1999 and again 26th July 2000 when a new replacement radio transmitter was fiited.

Her measurements were: wing 530mm (524 in 1999), weight 1820g (181g in1999).This female was ringed as a chick at nest number 68 in a Forestry Commission forest in Ross-shire on 10 July 1991 and was a single chick, identified as female.

She has been breeding for the last seven or eight years at nest number 57 and has been very successful, rearing 13 young in the last 5 years. Single young have been translocated from this nest each year to Rutland Water (until 2000) and all have migrated successfully. In 2000, last year's mate failed to return and S06 mated with a new male, S18. They had three eggs and two young. In 2001 S06 mated with S09 and produced 3 eggs. S18 then arrived late and evicted S09. One chick hatched.

S06 was the parent of bird R03(1999) and , with S18 of T04(2000). Monitored by Roy Dennis.

 

Migration in autumn 1999 and spring 2000

In August 1999 S06 made a surprisingly early start to her migration and we received no data showing whether the bird stopped on its way to Spain.

After a short stopover at the large reservoir of Gabriel Y Galan, between the Sierras west of Madrid, S06 moved 50km south near to Parque Naturel de Monfragüe where she stayed for over 2 months. Several accurate locations showed that the bird was ranging around an area about 10km square. She was seen fishing on nearby Alcantara reservoir by Roy Dennis on 2 November. (Click for details).

By 14 November she had returned to the more northerly reservoir where she remained during the winter.

By early April she had moved back to the area of her nest site. The lengths of the legs of her return migration were 304, 385, 587, 856km. This is a total of 2132km in a period of 12 days - 178km per day.

Map produced using DMAP software

 

Migration in autumn 2000 and spring 2001

S06 returned to one of the reservoirs where it spent much of last winter. It is interesting to compare the southward route shown here, with the one recorded last spring - scroll up to see that map and details.

This journey took 17 days and the total distance between plotted points is 2800km. On September 18th it was seen and photographed at the Embalse (reservoir) de Gabriel y Galan in Extremadura. It remained there throughout the winter and we received good quality transmissions most weeks.

By 4 April S06 was again back in Speyside, but unfortunately we did not receive any intemediate positions allowing us to plot her route. During the summer, good quality daily transmissions were received.

On 11th April, a male bird with a satellite aerial was noted at the nest and we were amazed to find the following day that this was the young bird S09 from Norway, and not her last year's mate S18. They laid 3 eggs and started incubation. But on 28th April S18 arrived back in Strathspey and evicted the young Norwegian male from its nest site. It then stayed at the nest, and helped raise to flying stage a single chick which was probably not its own.

Map produced using DMAP software

Breeding in 2002

S06 returned again and bred successfully with S18. She is now 11 years old and an experienced breeder.
She arrived between 28th March and 3rd April, laid 3 eggs and reared two young. We wonder if she again wintered in Spain.