The litter left behind by visitors has become a health hazard for the deer, with research conducted by a conservation group finding plastic in the stomachs of nine out of 14 deer that had died in the park of unknown causes in 2019. [...] Prefectural officials placed three trash receptacles inside a bus terminal within the park and three outside of the terminal in the middle of January and kept them there for a month. During that trial period, the officials studied what type of trash was being thrown away, among other points of consideration. "Most of the trash was from people walking while eating, and so we saw no problem with making their installation permanent," the official in charge said of the trash cans. To prevent the deer from eating out of them, the trash cans have lids with handles—these must be pulled down like a mailbox to place trash inside. The bins are also sturdy enough that the deer can't knock them over.