The Cabin View

The Cabin View

Sunday, August 4, 2019

Sometimes It's Hard To Help Mother Nature

Whoever said you can't mess with Mother Nature is correct AGAIN.  We see it with the polar ice caps melting.  I read recently that Greenland lost 11 billion tons of ice in one day.  As most of my friends know, for several years I have been raising Monarch butterflies from egg, to caterpillar, to chrysalis and then to the adult.





I have blogged about it many times and enjoy it so much.  The feeling of seeing the process never gets old.  Now in light of new developments, I have to suspend this activity.  At least until scientists change their minds about the value of this activity.

There are a few reasons for this.  The first involves scientific evidence that this activity doesn't really help increase the population.  I can't imagine why it doesn't make a difference with so many individuals and school classrooms doing it, but scientists say that even if it is effective for some species it doesn't help the Monarch butterfly population.  They say it may even have a negative effect.  There is not much of a risk on the small scale if they are being watched for educational purposes or enjoyment.  The risk is when the Monarchs are being raised in high numbers in a captive situation.  There are companies that sell Monarch caterpillars.   The butterflies aren't used to being in such close proximity to others.  The chance of disease is greater than in the wild.  If unhealthy Monarchs are being released it's chance of survival is lower, reproduction is compromised and then migration is a problem because they are weaker.  Another article I read says they may be disoriented because spinning a chrysalis indoors confuses their sense of direction.  It is important to release the adult butterfly in the same area as the egg was collected.  The last argument is that over time the genetics can be changed.   

I really want to do what is best for the Monarch butterfly population.  I also had another problem this year.  It had never happened before, but one of my caterpillars was parasitized by an adult female Tachinid Fly.  What happens is the fly lays eggs on a host.  This fly is beneficial most of the time because it helps control garden pests like tent caterpillars, Japanese beetles, cutworms and other pests.  The downside is that this fly also feeds off Monarch caterpillars.   A few days ago I noticed one of my caterpillars had formed the "J" shape.  Usually within a day they spin the chrysalis.  This caterpillar was going through the motions and suddenly it stopped moving right before I went to bed.  In the morning I found a four inch thin white strand hanging from the caterpillar.  The caterpillar was dead.  I learned that after this fly lays eggs on the caterpillar, a larva hatches and burrows inside to feed.  This kills the caterpillar and when the fly larva emerges it leaves a thin white strand.  The larva is worm like but soon hardens into a reddish capsule resembling a bean.  This is the pupa stage.  In a couple days a new fly hatches from the pupa and the process starts all over. 


I won't include a picture of the dead caterpillar with the thin white thread.  It is just too sad looking.  I couldn't find the "bean" but disposed of the dead caterpillar hoping none of the others were parasitzed.  As a precautionary measure, I took everything out of the habitat except the hanging chrysalises.  I cleaned it and one by one replaced the caterpillars onto fresh milkweed leaves.  I did find two "beans" and destroyed them.  Hopefully they hadn't hatched yet.  If they have, we may be in for more tragedy.  Everything looks good right now.  I just want to raise the caterpillars and chrysalises I have to adult butterflies.  Then that will be the end of that.  I really enjoyed the process but what I can do now is provide an outdoor habitat with lots of milkweed plants and never use any pesticides. 

Hopefully future studies will prove this latest information incorrect, but until then I will love and enjoy these beautiful butterflies in my yard.

1 comment:

  1. After my experience I will not raise anymore inside but I will plant more milkweed varieties and native plants for the butterflies!

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