Found dead on 10 May 2016, floating without head. No injuries or signs of trauma (aside from the obvious lack of head). Notches visible in marginal scutes are for identification (C. picta #498), not signs of attempted predation. Maximum straight-line carapace length is 13.8cm.
Habitat is a pond with standing dead snags and shorelines fringed with Phragmites and honeysuckle.
Any thoughts on what would decapitate a turtle but not eat it? A similar event occurred last summer at a nearby wetland.
Field Notes - Ottawa national wildlife refuge driving tour. two turtles sunning themselves. distinct point along shell and yellow "contour map" lines on skin.