Stanley the white-tailed eagle flew off during a show in September and despite a number of sightings handlers were unable to catch him.
He was first spotted in Leamington and was later seen in a tree in Preston Capes, Northamptonshire, in October.
A Warwick Castle spokesman said staff had not given up hope of him returning but admitted it was unlikely.
The general manager of the tourist attraction, Tim Harrison-Jones, said: "We had a few sightings over in Northamptonshire and we sent our falconers out to go and see if they could find him.
"We located him to a tree but he was feeding quite well on what we think were dead rabbits so the falconers have decided to leave him.
"What we hope is he'll make it to the coast. If he can make it to the coast he'll have a really good life."
Stanley, who is aged over 10, has a wingspan of more than 6ft (1.82m). He is named after Kazakhstan, where he is originally from, and had been flying at the castle for more than eight years.
For more on this story see the article on the BBC web-site here.
Member since: 9th July 2012
I'm a keen guitar player & musician who plays in our family band. Our highlight so far was playing to 10,000 people at Fairports Cropredy Convention in 2010 & featuring on Bob Harris's Sky Arts prog.
The following Cookies are used on this Site. Users who allow all the Cookies will enjoy the best experience and all functionality on the Site will be available to you.
You can choose to disable any of the Cookies by un-ticking the box below but if you do so your experience with the Site is likely to be diminished.
In order to interact with this site.
To help us to measure how users interact with content and pages on the Site so we can make things better.
To show content from Google Maps.
To show content from YouTube.
To show content from Vimeo.
To share content across multiple platforms.
To view and book events.
To show user avatars and twitter feeds.
To show content from TourMkr.
To interact with Facebook.
To show content from WalkInto.