Earlier this summer six young white-tailed eagles were collected from nests in Scotland and translocated to release aviaries on the Isle of Wight at the start of a new five year project aimed at restoring this species back to the south of England (see here).
This conservation initiative is being led by the Roy Dennis Wildlife Foundation and Forestry England, with a number of other supportive partners.
[WTE Reintroduction Project team Steve Egerton-Read, Dr Tim Mackrill, Ian Perks, Roy Dennis. Photo by Robin Crossley]
A project update blog has been published (here) and it announces that one of the eagles has died (the post mortem was inconclusive about the cause of death but further tests are being undertaken) and other eagle’s tag has stopped transmitting from the mainland. The missing eagle is named ‘Culver’ and is the bird whose spectacular London fly over caught the public’s attention in early September (see here).
Of his disappearance the blog update says:
“We have analysed the tracking data, consulted with the police, and other experts. We have also conducted both ground and aerial searches in the most likely area using radio tracking equipment (all birds are fitted with a radio transmitter in addition to the satellite tags). However to date we have not been able to determine his location. There have been sporadic unconfirmed reports of white-tailed eagles from various locations and therefore we are keen to hear from anyone who may have seen Culver or any of the other birds“.
Raptor Persecution UK 
There is a eagle spotted at Christchurch dorset stony lane roundabout. Check the dorset echo website also.
Is there any research on mortality rates amongst young raptors comparing ‘natural’ with released birds?
Good question, Secret Squirrel and the answer is yes!
Most pertinent is Evans et al (2009) Growth and demography of a re-introduced population of White-tailed Eagles. Ibis 151:244-254. This paper focused on the reintroduced Scottish population and found that survival rates of released WTE were lower than those of wild-bred birds, especially during the first three years of life.
However, the discussion section includes this:
‘Brown et al. (2006) found a similar difference between recruitment rates of wild and released Aplomado Falcons Falco femoralis, combined with even greater differences in annual survival rates for pre-breeding birds than found in this study of a slower-maturing species. However, studies of re-introduced Red Kites
Milvus milvus (Evans et al. 1999) and Mauritius Kestrels Falco punctatus (Nicoll et al. 2004) found no difference in survival rates of wild and released birds, so such differences cannot be assumed for
re-introductions of all raptors’.
Thanks, some light reading for the weekend!
It’s obviously also a relevant question for brood meddled Hen Harriers