Dispatch From the Butterfly Ranch

Egg, larva, pupa, adult - the four basic life stages in an insect’s life cycle.  I’ve been visiting each of these stages this season on the Butterfly Ranch mostly as it relates to monarch butterflies.  Things are winding-down here at the ranch so there is a high probability this will be the last installment for 2019.  We'll see. 

It takes monarchs about a month to go through the stages from egg to adult and once it has attained adulthood the butterfly will live another two to six weeks and may actually participate in the migration south. 

Two weeks ago I had the unique opportunity to observe a monarch caterpillar pupate. 
I published and account of it here.  This is the fourth and final installment on the story – an adult emerges. 

The primary job of the adult stage is to reproduce the species.  When monarchs mate they remain together for as long as 16 hours with the females laying eggs almost immediately.   

click on the images for a closer look

Last Friday, August 30th, I checked on the pupa that was hanging from the siding adjacent to the front door.  It had previously begun darkening earlier in the week indicating that the emergence of an adult was nigh.  In the photo above you can see the wings of the butterfly encased in the pupa.  And then BOOM - this happened.  The adult emerged and was almost finished drying its wings when we found it.  

This butterfly is the final generation of monarchs - the adults that emerge in late summer and early fall.  As a consequence it has the job of migrating to overwintering grounds in Mexico.  There the adults spend the winter roosting in trees until conditions are favorable for their return to their breeding grounds.  These adults can live up to nine months.  Here is the monarch that emerged almost ready to take flight. 

The monarch that emerged in this picture happens to be a boy.  Field marks to look for to distinguish one sex from the other are on the wings.  The veins of a male’s wings are thinner and more delicate than those of the female.  Furthermore, males have a black spot on a vein on each hind wing that is not present on the female.  These spots are made of specialized scales which produce a pheromone used during courtship in many species of butterflies and moths. Remember to look for the 'balls' on the boy monarch. 

Bon Voyage little fella!