Polyphemus Moth ecloses in dead of winter

Subject: Help – our moth hatched and its snowing outside!
Location: Columbus, Ohio
February 16, 2014 7:28 am
Hi. My kids found a big fat green caterpillar and brought it in the house. The first night we had it, it made a caccoon. This was 18 weeks ago. We thought it was dead – but it hatched last night. We live in Ohio and its snowing with 20 degree temps right now. Do we set it free or keep it inside? What do we feed it?
Thanks for your help!
Shelly Breehl & Family
Signature: The Breehl Family

Polyphemus Moth
Polyphemus Moth

Dear Shelly and the Breehl Family,
This is a Polyphemus Moth, a member of the Giant Silk Moth family Saturniidae.  Setting it free with sub-freezing temperatures will result in instant death.  Keeping the moth indoors will most probably result in a longer life than it would have in the wild where it would have to avoid being eaten by predators.  Giant Silk Moths do not feed as adults, but the caterpillars have a ravenous appetite.  Fat is stored in the body of the caterpillar and this is used to help sustain the adult moth long enough for it to mate and reproduce.  The life span of an adult moth in the wild would rarely be longer than a week.  It is difficult to be certain, but your individual appears to be a female.  The antennae of the males are much more developed and feathery because the male uses his antennae to locate a female, sometimes from miles away, because of the pheromones she releases upon emergence from the cocoon.  When we are asked for advice on keeping caterpillars, we always advise keeping the cocoon or pupa at approximately the same temperature as the outdoors to prevent early eclosion in areas with a harsh winter.  Though this Polyphemus Moth may live as long as two weeks in captivity, it will not be able to mate and reproduce.  Reproduction is the primary goal of the adult moths.  If this is a female, she will most likely lay sterile eggs.

Thank you so much. This helps a lot!

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