There was a period here earlier in the season when I had quite a few and then they seemed to have vanished for 2 or 3 weeks but they are back now. Where they went I do not know.

I'm in Ohio, and I noticed they weren't around for a few weeks, but recently they've showed back up.... I wonder if it is related to females incubating and raising young, if they stay closer to the nest during that time...? Operation Rubythroat indicates the females spend 55 mins of each hour on the nest for a few weeks:
http://www.rubythroat.org/RTHUReproductionMain.html#anchor2360946

Probably nesting. I had sightings diminish earlier for a couple of weeks in spring. Then a few weeks after they were frequenting the feeders again, I noticed that some of the birds were much smaller-most likely juveniles. I think the females may be getting ready for a second round of nesting, if they haven't already started. The larger females were looking rather rotund.

It seems my hummers have disappeared all together :-( as well. In WI this is usually the start for the season for me. Usually in August I may have 10-15 hummers. It has been cool here in WI I wonder if that has anything to do with their feeding?

Or if it could be the more frequent visits of my neighbors Retriever. I wonder if her barking is scaring them away?

Monica

I would guess that you are just having a little lull in the action especially this time of year , whats going on here is I have action then they move out and I might have very little action for a couple of days untill more move in. In a couple of days you should see more.

Steve

Nesting and the increase in natural food sources can cause the visits to your feeders to decline in mid summer.

Hummers nest twice in one summer?

At the beginning of the season I only saw my male everyday.
Now I haven't seen him for 6 days. He was very regular to the feeder and perched in the top of my hawthorn every morning. I have seen the female dancing in the sprinklers (thats how they bath)every time they are on.

What I have read ( I am by no means an expert) is that while nesting and the hatchlings are young the female needs mostly protein from insects to feed the babies so she doesn't take a lot of nector. The males begin the return south sooner than the females and this leaves less competition for the new hummers to get strong for the flight south.

Laurie