I think that doggie was performing an important and long forgotten traditional ritual involved with baptising kayaks:

from surfing the net at www.artickayaks.com/hooptext.htm about the rituals associated with finishing a kayak

"... the frame is shoved into the completed covering, the now naked owner [see it could have been worse], accompanied by all the men present, sings his childbirth song to his new kaiak. THE OWNER WASHES THE COVER WITH URINE TO REMOVE ANY OIL THAT MAY ADHERE TO THE SURFACE ...."

I guess he was just saluting the fact that it was once a tree. Wonder if he would've done it to a plastic kayak?? Bad, bad doggie!!