Do All Monarchs Migrate?

[tartandtiny]

Do they all migrate? I live in central CT and have seen Monarch's in different area's of the state every day over the past week. I am surprised to still see them, I thought they would have been on their way to Mexico at this point. The weather here is in the mid 50's to high 60's.
It just seems too cold for them to still be fluttering around in NE.

[psi_chemie]

The way they reproduce is the later in the season, the higher percentage of monarchs are nonproductive migratory. But some fraction does reproduce, and so you get late eggs and larvae that keep going as long as there is food and it hasen't frozen hard. So you often find late monarchs, and wonder what their chances are. It is all chance. Some will make it. Or a cold snap could come through and put a total end to the season. You never know.

[Mona Miller]

The way they reproduce is the later in the season, the higher percentage of monarchs are nonproductive migratory. But some fraction does reproduce, and so you get late eggs and larvae that keep going as long as there is food and it hasen't frozen hard. So you often find late monarchs, and wonder what their chances are. It is all chance. Some will make it. Or a cold snap could come through and put a total end to the season. You never know.

I think that cold weather pushes them further north. I've noted that they do think a bit about what they are doing. One friend has noted caterpillars hanging out near rocks and those would retain more heat. Another friend told me that they pupated on the siding of her house on the east side, the sun rises in the east and houses give off heat. The adults roost in trees, the trees would provide shelter.