The guys behind the Strange Statues around the World at haha.nu came up with a dedicated website to keep track of these strange statues. This one is The Headington Shark:
The Shark became the most famous resident of Headington when it landed in the roof of 2 New High Street (see map) on 9 August 1986.
This ordinary home (built as a semi-detached house in about 1860 but now attached by a link to a second house to the north) suddenly became the centre of world attention, and the headless shark still excites interest today.
http://saoma.com/central/ - Thanks Quong Pham!
(bit of a misty picture I'm afraid)