Nectar doesn’t seem to get their attention. But cheap Walmart brand Concord grape jelly works great. My feeder only has one really small dish for jelly, and they clean it out as fast as I fill it. I’m ordering a bigger one today that holds an entire jar so I don’t have to fill it two or three times a day. Started with a small feeder just to see if it would attract orioles. Didn’t know if we had any around, but apparently we do.