Out at my place in N Texas, a couple of times they have come thru in the fall. I"ve seen the sky full of them for hours at a time. 1000s of them. It seems that they must fly high up and late afternoon they decend as it cools off. Then they roost overnight.
Males have a single small oval spot, (on one black vein) on the inside surface of both their hindwings, that is not present in females. This spot is on the vein nearest the butterflies body, and fairly near the tail of the abdomen. Check the photo and it will be easy to spot!
something this small and fragile travels 1000's of miles and most of us will jump in the car to go a few blocks. I have been a monitor for the northern illinois butterfly monitoring network for 12 years and have been keenly interested in butterfly and small amphibian life since i was a kid (in the 1950's). i'm still seeing monarchs and other butterflies in the chicago area. some of my recent sightings.......................
What lens/camera/tripod system are you using . . . is is obviously not your first rodeo!
I shot the image above with a Canon t1i with a Canon EF-200mm 2.8II L telephoto. Unfortunately the first few shots were WITHOUT a tripod, so I shot in Av mode adjusted to wide open @ 2.8 (in order to get a marginally fast shutter speed of 1/180 I'd need).
Then, I quickly thought better and grabbed the tripod but DIDN'T adjust the aperture to 5.6 or smaller (I prefer 8.0 if I can keep ISO noise down too) in order to get a deeper depth of field needed to keep most of the butterfly sharp.
Live and learn of course . . .
Heck, I usually attach my electronic shutter release too (when I have the time), compose quickly on the tripod but then fire from the remote button to avoid camera shake.
So . . . I have this marginal photo with the wings flat as my current "best" Monarch shot with my Canon DSLR. Still, I love the superb bokeh of this fabulous Canon "L" lens!