Last year we had at least 8-10 Hummingbirds coming to our yard and feeders. The wasps and bees moved in and overtook them all. We purchased new ones that had great reviews and bees and wasps could not get anything out of but the hummers don't have a problem. After changing them out the hummers acted like they didn't recognize them as feeders. It was late in the season and most were starting their migration. This year we put out the feeders and I watch the hummers come in the yard and look around and they do not recognize them as feeders. Has anyone else had this problem and how do we get them to know these feeders are ok?