An interesting observation of Mutualism

An interesting observation of mutualism the other day @tumaren_camp; While having tea a Hare hopped into view and immediately was joined by a Northern White-crowned Shrike who landed on her back. The Hare assumed a docile posture laying her ears down so that she could be inpected for ticks, which the Shrikes (the first bird was joined by another) promptly removed. How cool that we can live in a place for so long and still be taught biology by our familiar animal neighbors. Has anyone ever seen this before with these speceis? Is there another shrike that practises this kind of mutualism?