Mourning

I’m mourning the loss of 7 chrysalises due to a predator previously unknown to me.

My tendency is to photograph and write only about the wonders of the butterfly’s development because it’s the beauty of change that inspires me.  But this morning as I gathered the infected chrysalises in a bag I realized that this too needs to be documented.  A butterfly’s untimely death needs to be honored as much as its life.

Today is Saturday.  I workout every Saturday at 6:15 am.  The alarm startles me from a sound sleep and from my cozy spot under the covers with my husband’s arms wrapped around me.  My body gets up, but my mind stays in bed.  I don’t want to work out; I am frustrated because days earlier I aggravated a healing sprained ankle and I know this will limit my workout.  I am grouchy but I go anyway.

After my workout, I head down the hallway to start a load of laundry and notice out of the corner of my eye a chrysalis dangling a silk thread.  There are several floor to ceiling windows in my house that look out onto my atrium, in case you’re wondering about the logistics of seeing this from within my house.  This is not the first “dangling thread” incident this week, merely the newest one, and suddenly I’m mad and want to know what’s happening.  This has become more than just a few isolated cases.  So I take a detour to my office to do an internet search.  I could go one with the whole “woe is me” story that started my day but really, in the scheme of things, my problems are small.

Warning, the squeamish may want to stop here.

Until today I have never heard of the Tachinid fly, but apparently the species to which it belongs is the largest and most important group of insect parasitic flies in North America and a frequent predator of the Monarch.  Whereas the Monarch host is the Milkweed plant the Tachinid host is a caterpillar.  There are several ways in which a caterpillar can be infected.  The Tachinid either injects the caterpillar with an egg or lays the egg on the surface and when the egg hatches the larvae bores into the caterpillar.  Think of a caterpillar, which is also a larvae.  The caterpillar eats, grows and molts before finally becoming a chrysalis (pupa) that then produces a butterfly.  The Tachinid process is the same except most of the development is done within the caterpillar and while the caterpillar continues its development.  The caterpillar doesn’t even know that anything out of the ordinary is happening (or so I’m led to believe in my readings).  The silk thread dangling from the Monarch chrysalis is a sign that the Tachinid pupa has been ejected.  It’s too late for the butterfly; it is dead.  But the Tachinid pupa will soon eclose (hatch a new fly).

I warned you it would be yucky.

I guess the trick is to identify an infected chrysalis before the Tachinid pupa is ejected, that is if I can find the chrysalises to inspect them.  I must look for signs of discoloration, abnormal brown or black spots, shrinking in size or the formation of a dark ring around the top.  These are signs that the butterfly within is dead.  It’s too late for the butterfly, but not for the Tachinid inside.  Until the silk thread appears the Tachinid pupa is still within and the idea is to destroy the chrysalis before the Tachinid pupa emerges.  So I can’t just remove the chrysalis and quietly place it in the trash giving it a dignified send off.  No, I’m supposed to freeze or crush the chrysalis in a sealed plastic bag.

This group of caterpillars/butterflies has been particularly troublesome.  For one thing it’s generated the most visible deaths.  Usually caterpillars that aren’t going to make it simply crawl off somewhere to die.  That’s not been the case this time.

But this group has also been my largest so an increase in deaths is expected if its relational.  There’s always some caterpillars that will starve because there will never be enough Milkweed.  Some caterpillars will wander into spiderwebs and some chrysalises will be found by spiders.  I’ve gotten used to that.

The deaths this time have been different.  In addition to the butterfly dying in the chrysalis I’ve had several caterpillars die while hanging straight from “the best spot”, never forming their “J” and ultimately their chrysalis.  There is still one hanging from the top of my atrium wall because I need to get the ladder out to remove it.  I wonder if these too have been infected by the Tachinid fly.

Today my atrium feels more like a mortuary than a sanctuary.  I am discouraged by the loss of so many caterpillars and chrysalises.