Duck was, at one point, one of the most prolific taggers in Ann Arbor. If comments on webpages can be viewed as reliable sources, Duck may have been from Spain. Despite rumors, Duck is neither a crime-fighter nor a gang.
The tag is often seen with a tilde over the u. I'm not sure how to pronounce that. This one is on the dumpster behind Fleetwood.
Another Duck tag on the Fleetwood.