Tag Archives: Monarchs Mating

SAY WHAT! MONARCHS MATING IN SEPTEMBER???

This pair of Monarchs did not get the 411 that they are supposed to wait until next spring to mate!

Beginning in early spring, Monarchs depart Mexico. They lay eggs of the next generation and then perish. This next generation moves northward depositing their eggs on emerging milkweed. It takes four to five generations to reach the Monarch’s northern breeding grounds, of which Cape Ann is a part. The Monarchs that we see in the early summer only live for about four weeks.

The Monarchs that eclose at the end of the summer are a super generation of Monarchs. Another way to think about them is that they are also referred to as the ‘Methuselah’ Monarchs. This last brood of the summer lives for a very long time for a Monarch, about seven to eight months. The Methuselah Monarchs that we see migrating today will travel south all the way to the trans-volcanic forested mountains of central Mexico. They sleep through the winter in butterfly trees in a state of sexually immaturity known as diapause, then awaken in spring to move northward and deposit eggs of the next generation, thus completing the circle of the Monarch’s life.

So that brings us back to this atypical pair mating in the marshy meadow in September. Every year during the annual southward migration I see at least one pair of Monarchs mating. I wonder, will the pair survive and continue to migrate? Will their offspring survive and travel further south?

Please join me Saturday, October 5th, at 10:30 at The Stevens Coolidge Reservation in Andover for a Monarch Migration Celebration and for my conservation talk about the Monarchs. For more information, see here.

How to Tell the Difference Between a Male and Female Monarch Butterfly

For Devera, who wrote in asking how to tell the difference between a male and female Monarch Butterfly ~

Click photos to view large.

The first photos shows all male Monarch Butterflies necatring at Seaside Goldenrod. Notice the pair of little black pockets, or dots, on the inner vein of the hind wings. These are pockets of pheromones, or what scientists actually refer to as “love dust,” which the male sprinkles on the female during courtship.

The female Monarch Butterfly lacks the the black pockets on her hind wings. Notice too that her wing veination is thicker and smokier.

 

During courtship, male and female join, and he carries her to higher ground. This photo shows the male and female mating, with the male above.