Spring Migration of Midwestern-born Monarchs

[ChrysCook]

Wondering if anyone knows for sure whether the monarchs that emerge in late spring / early summer in midwestern areas such as southern Indiana usually go north or do they usually mate & lay eggs locally? I see monarchs in my wild meadows May through October and have assumed the ones I see in July and August emerged from eggs laid by the ones that arrived earlier.

[Paul Cherubini]

In May and early June both phenomena are happening; i.e. the butterflies are mating and laying eggs locally as well as moving north inbetween bouts of mating and egg laying. In late June some of the butterflies are still moving, but in more variable directions besides north; i.e. a recent stable isotope study showed some midwestern monarchs in late June fly east and even southeast and cross and Applachian mountains.

[ChrysCook]

Thanks, Paul! So some monarchs may spend their entire life locally, provided there are nectar sources and milkweed available? I saw more monarchs and big cats on my meadows this year than ever before, including these on July 18, assuming that was the case. Documentaries I've seen, like the recently aired NatGeo's "Great Migrations", don't go into much detail about the spring migration, and I've never tagged them to know if I was seeing the same monarchs for several weeks, so I thought I'd check what others knew.

It was exceedingly dry in this part of the country summer and fall, so things like the New England asters didn't bloom at all in many places. In my meadows, the goldenrod, ironweed, and mistflower did okay for nectar sources for any late-staying monarchs or ones travelling through, though everything dried up much earlier than usual.

2 big cats on milkweed in upper meadow

Two monarch cats on milkweed.jpg (46.5 KiB) Viewed 1744 times

[Mona Miller]

http://rsbl.royalsocietypublishing.org/ ... .0525.full
Monarch butterflies cross the Appalachians from the west to recolonize the east coast of North America

I participated in this study. Nathan did not get to collect milkweed or monarchs from my area. I ended up sending a few monarchs and milkweed samples.