Ornithological correction

In a posting regarding what I did on the Big 5-0, I referenced a field of what I called "crows" who were grazing en masse on a grassy knoll in Hendon. I would like to clarify this, if possible.

Amazon.co.uk just sent me my copy of "Birds of Britain and Europe" by Jim Flegg, illustrated by Martin Woodcock. Now isn't that a good name for a person who paints bird illustrations, or perhaps that is his porn-star name? (Aside: One way of determining one's porn-star name is to use the name of your first pet, along with the name of the street on which you grew up. If more than one street, pick the one that sounds the best with the pet's name. My porn-star name would be Abi Roxbury, who in a perfect porn-bod world, would have amazingly flat abs. But I digress)

The illustrations under "Crows" inform me that the large Carrion Crow Corvus corone, (Corona-drinking crow) as seen at the Tower of London, inhabits open countryside, has a widespread range, but is rarely very numerous. On the other hand the Rook Corvus frugilegus (Frug-dancing crow) is colonial when breeding and gregarious when feeding, with a widespread range and is often common. Another candidate is one of the smaller crows, the Jackdaw Corvus monedula (Monedula-doing crow), which is gregarious, often in large flocks with Rooks, inhabiting open woodland, parkland, farmland and urban areas, nesting colonially, with a widespread range and often common. 'Ere, 'oo you callin' common? they cry moneduliciously. I would bet that that was what I saw doing exercises near the football club in Hendon: a highly trained drill-team of jackdaws.