The Flight of Bird U06 (2001)

Osprey U06 is a female. It was translocated to Rutland Water on 15 July 2001 and released on 31 July. Just before release this bird weighed 1700g and had a winglength of 495mm. BTO ring number 1385681.

U06 was a very large bird and was dominant in its pen before release. It had an unusually dark head pattern and carried a battery-powered radio transmitter.

Picture: Bryan Tew
  

5 days after leaving Rutland Water, U06 was 1500km away in western Portugal. It seems likely that it crossed the Bay of Biscay to northern Spain and then flew south. During 8 September she flew 165km in four and a half hours.

Surprisingly U06 did not continue on to West Africa, but stayed in Portugal for the autumn, winter and spring, making only short flights.The position to the north east of Lisbon, very close to the Tejo Estuary Natural Park and Paul do Boquilobo Natural Reserve, was similar to the position used by S08 for a stop-over in 1999. Below right is a large-scale map showing some of the good quality locations we received. There appeared to be two favoured areas about 30km apart. Regular good quality transmissions were received from the same area throughout the winter and into the spring of 2002.

Then suddenly, in June 2002, U06 unexpectedly returned to England. The location on 4/6 was not an accurate one but by 9/6 she was certainly in North Yorkshire. On 21/6 she was north of the border and off St Abb's Head at midday, returning to the mainland by late afternoon.

Once again U06 surprised us, since usually juveniles are at least two years old before they return. Unfortunately, we received no further transmissions from U06's radio, leaving unanswerable questions about the bird's survival... until 2003.... see below.

Riddle of a red-ringed Osprey

At the end of April 2003, a female Osprey was seen for the first time at Rutland Water with a red ring on its right leg. Initially the ring number could not be read, so we set about working out what the possibilities were. Only three female birds had been translocated in 2001 and all three had been satellite tracked:

  • U03 Migrated 27/8/01. Probably perished in central Sahara where it arrived less than 18 days after leaving Rutland Water.
  • U06 Migrated on 23/8/01. Its body was recovered from a beach on Fuerteventura, Canary Islands, on 12/9.
  • U06 Migrated on 3/9/01. Spent the winter and following spring near Lisbon, Portugal (most unusual). Then moved north through the UK in June 2002 until transmissions ceased near St Abbs Head.
  • Other possibilities were the 2001 Rutland-bred chick which may have been female, or a Lake District chick, or a much older Scottish female from 1996.

So which of these birds could it be? Volunteer Ian Matson finally managed to solve the riddle of the red-ringed bird by reading the ring number. It was U06, once again doing the unexpected. Conventional Osprey wisdom says that females are much less likely than males to return to the sites from which they fledged.

There was no sign of the transmitter which must have come off the bird's back as they were designed to do.

U06 was seen again - very frequently! In 2003 she bred at Rutland Water - click here for details. However, she did not return again to breed again in 2004. Perhaps she perished during the winter, or perhaps yet again she will turn up when we least expect her!

©2008 Rutland Osprey Project.
Photographs and images by members of the Project Team unless otherwise stated.
The project is a partnership between Anglian Water and the Leicestershire and Rutland Wildlife Trust,
with funding from Augean Plc through the Landfill Tax Credit Scheme.
The project is based at Rutland Water Nature Reserve.