When first approached near the fence separating Crow's Nest from Mardaneus Plaza, you witness him giving an inspirational speech to his fellow Champions. Bubo is motivated to spontaneously charge into Crow's Nest, and is quickly struck down by lightning cast by the great tree, Nericon. He asks for your help, and approaching the tree begins the quest Bark up the Right Tree.
This is a hint that he would like the Miniature Zeppelin received from Dr. West at the Circle of Trust Inn during the quest Mind over Matter. In exchange, he'll give you a Compass that may be of interest to a fellow Champion.