Holly Faulkner, Project Assistant says:

Hi John, your orioles may already be beginning their nesting processes (which takes them away from feeders as they focus on building their nest), or it could be that they don’t feel comfortable coming own to your feeders. Some birds are more skittish than others – sometimes adding brush piles or other “cover” near a food source can help encourage birds to visit. For orioles specifically, try providing orange halves or natural grape jelly to attract them as well. If you have further questions, please email us at feederwatch@cornell.edu – these comment sections are not regularly monitored.