Keith Turner sent in this series of photos of a crow grappling with a discarded beer can on the Forest Recreation Ground :
This is a Carrion Crow, Corvus corone, a very familiar resident of all areas of the city. They are intelligent and curious birds, and will readily investigate interesting-looking objects – including, in this case, shiny litter.
Thanks to Keith for the photos. More examples of his work can be seen on his flickr page.