Black Death in Monarch Butterfly caterpillars and chrysalidesWhy Are My Monarchs Turning Black?

Black Death in Monarch Butterfly caterpillars and chrysalidesWhy Are My Monarchs Turning Black?

Why Are My Monarchs Turning Black?

A certain percentage of monarch caterpillars and chrysalides just don’t make it into
adulthood and become butterflies. They may show signs of disease or parasitism.
It is heartbreaking but also common. Nature does not intend for them all to
survive. In fact, left alone, a very small percentage make it from egg all the way
to butterfly.

“Black Death” is when a caterpillar looks healthy one day and then the next it gets
lethargic, then darkens and its body deflates and turns to mush. Or what looks like
a healthy chrysalis turns dark and mushy. In most cases, black death is caused by
either a bacterium in the genus Pseudomonas or by the Nuclear polyhedrosis virus.

Read how all about it and how to help prevent NPV in your monarch garden:
https://www.thoughtco.com/why-are-my-monarchs-turning-black-1968453