(continued from part i and part ii)
By Sunday morning, the previously-sleepy butterfly, whom Dan named Isabella, was fluttering around in the bug habitat (good move cooping her up overnight), eager to fly. Xander was fascinated and delighted by her movements.
Halloween preparations notwithstanding, she needed to be set free. Dan told the kids that she needed to set out for her trip to Mexico. Griff thought we were being silly, and we explained that actually, monarch butterflies that eclose East of the Rockies migrate to Mexico in the fall, while monarchs who are born West of the Rockies migrate to a spot in California.
This sparked interest in the lifespan of monarchs. Do all the butterflies from a whole summer journey to Mexico? Do they live long enough to get there (some of them must, right? otherwise it wouldn't be much of a migration)? How long do they live there? What I've learned is that the first couple of generations of butterflies each year - those who emerge in early and mid summer - have shorter lifespans, about 2-6 weeks, or a maximum of about two months, which is not long enough to live until and/or through the migration. Those who emerge later in the summer and early fall enter a non-reproductive diapause that enables them to live longer - up to seven or eight months - thereby enabling them to make the trip and live long enough to overwinter. This generation waits to reproduce until they leave their winter home in February or March.
I had been told that the generation that journeys South is not the one that returns in the spring. That is not entirely true; the overwintering generation does make the journey South and then starts the journey back to their original breeding grounds...but they do not make it all the way. It is the first or second summer generation that return all the way to the Northernmost habitats of the monarchs.
So this little butterfly, if she is to fulfill her genetic destiny, has a long trip to Mexico and most of the way back ahead of her.
She's pretty eager to start.
Earlier that day I had offered fruit to her, but I'm not sure she drank any of the juices, which made me a little concerned about her energy reserves, since there are not many flowers in bloom here in late October. We'll have to hope for the best.
I taught the kids how to hold a butterfly by the wings and now Griffin showed his new skill.
He set her on the patio table.
I gave her a finger to climb on, and then she flew away...
...and rested on a bush...
...where she stayed for the rest of the day.
The last time I saw her was in the late afternoon, and she was still on the bush. I hope she was just enjoying the sun and resting up until she felt ready to fly somewhere to get a meal and then start the long journey.
Qué tengas un buen viaje, Isabella.
