So it turns out large black birds may be the avian kingdom’s answer to tool-users and social learning as the New Caledonian crow may be the only non-human species that seems to have its own cumulative technological culture!  I kind of suspected as much when I was writing about Cymri and, to be more fair, Cilgwri.

http://www.sciencedaily.com/releases/2015/08/150826113817.htm