The Ruby Throated Hummers are the only hummingbirds that migrate to Iowa. My first hummer arrived on May 1st 2005 at one of my feeders, but didn't reappear again until May 6th, joined by another male Ruby. They were very thin after their long and arduous migration. Fortunately, small insects are plentiful, their favorite nectar-rich flowers are starting to bloom, so my feeders were not their only source of food. Several other hummers have appeared in the past few days and have been visiting my four feeders from daybreak until dark. I believe this hummer may be the first one to have arrived because he is very territorial of the feeders and stands guard over the feeders most of the day, perched in a river birch right by the deck, fighting off any other hummers that approach a feeder. To reinforce his "swatters rites" he engages them in arial fights for several minutes, but, when he becomes tired and needing a refueling with nectar for energy, eventually relents and allows them at a feeder.