I found 2 caterpillars in all, in my row of 8 blueberry bushes. The first was a startling experience--the creature began flailing its front body parts wildly, back and forth. When I realized it was a caterpillar and approached it closer, it froze and hung limply from its center section, resembling a bird dropping. Eventually it started crawling and eating blueberry leaves again. The caterpillar has "feet" on the front (orange or rust colored) segment, on the hairy white zone, and at the back end. In between there are black areas with no "feet." These in-between areas seem to fold when the caterpillar goes limp, disguising itself as a bird dropping. The photo was identified for me by Hugh McGuinness of butterfiesandmoths.org.