My understanding is that Clojure also relies heavily on some of the advanced Hotspot optimizations that aren't available in Dalvik so it's often much slower on Android than it is on the standard JVM.
In my experience, most of the alternative compiled JVM languages, i.e. Scala, Clojure, Mirah, and JRuby, seem to run fairly comparable to each other once they have started. The biggest differentiator between them with respect to performance seems to be in the way of start time and heap overhead ranging from none (Mirah) to substantial (JRuby).