Monarchs hanging around?

[MILW]

I just recaptured one of my own tagged monarchs- he was tagged back on 9/8, so he's been in the area for the past week. There are lots of adults passing through, this is supposed to be the migration peak for 43 N, so I'm a bit surprised that he's still hanging around!

Anyone else noted this?

cheers- Scott

[psi_chemie]

Yeah, I think there is a gradient between 100% non-migratory through 100% migratory, so in the middle there is a 50-50 mix of migratory and non-migratory. If that's when you're tagging, and you always tag in the same area, expect to see some of your own tagged monarchs. Happens to me all the time. Sometimes over a week later, I re-catch one of my own. Then towards the end of September, I never see any hanging around.

[Mona Miller]

It is typical in areas with good nectar sources for Monarchs to stick around and fatten up for their journey. If the weather is not good for flying that will also keep them grounded.

http://whyfiles.org/006migration/
What about the mechanics of migration?
"As long-distance aviators, monarchs must know how to ride a good wind, and how to duck and cover in a bad wind, says Taylor. As we talked, he described the monarchs outside his office: "Today, the butterflies are low, out of the wind, they can't move into this wind. Tomorrow the wind will change to the northwest and they will use it to move to southeast. The wind will then change further and come from the north on the next day, aiding the butterflies as they progress southward. They ride these winds, and have all sorts of sensing capabilities to take advantage of thermals and winds speeds. This is like a military aircraft -- it's got all sorts of onboard computers." .... (access the website to read more)