A new bird landed in our garden yesterday. At first I couldn’t determine what kind it was. It almost looked like a baby owl at first glance. It had sloppy feathers, huddled on our pergola and its body language revealed it felt uncomfortable and out of place.
The Man had a better perspective from his office, including a camera with lots of optical zoom. It turned out to be a scruffy pigeon. We suspect it was a city pigeon that must be starving now there are no food leftovers to eat downtown. They need to expand their territory to find food. Clearly a suburb is not its preferred habitat and seeds are not its preferred food. At some point the bird left the garden. I hope it will not return. Our garden is not big enough for more pigeons. We already have three ringdoves and two turtle doves who frequent our garden. That’s enough.
It could be a juvenile wood pigeon (Columba palumbus), we are seeing some of these in our garden (in the east of England, just across the North Sea from you) at the moment, and their behaviour is just as you describe. When full grown they are considerably larger than the doves.
Example picture at: http://www.wildlifeinsight.com/4712/british-garden-birds-juvenile-woodpigeon/