2 Shares Ten years after Jefferson County Animal Control mounted a campaign called “There is no Poop Fairy,” bags filled with dog poop left by visitors in Jeffco Open Space parks for others to dispose of properly remain a problem that frustrates visitors and rangers. (Provided by Jefferson County Open Space) Mary Ann Bonnell spends a lot of time studying animal and human behavior as the visitor services manager for Jefferson County Open Space. Animal behavior can be a lot easier to understand. And few things baffle her more — among all of the weird things in a park system that attracts 7 million people a year — than when people leave bags filled with dog poop along trails for someone else to pick up.