Tuesday, June 8, 2010

Mystery solved

  A while back I posted this picture of a cocoon. I suspected that is was a Cecropia Moth. 

I waited patiently.... for it to make its appearance and here it is:

It is a Cecropia Moth (Hyalophora cecropia) , it is our largest and arguably our most gorgeous moth in the Saturniidae family. These are are our giant silk moths and include the Luna Moth, Polyphemus Moth, and Imperial Moth to name but a few. The Cecropia has a wingspan up to 6 inches. Females are larger than males, but males have gorgeous super feathery antennae. The one that emerged from the cocoon is a female.

  (The big blob of red goo between her eyes in this picture is her "blood" pumping throughout her body to expand her wings and body after emerging from the cocoon.)

The Cecropia Moth also goes by the name of Robin Moth in parts of its range. With all those chocolate and orange markings it is easy to see why they are called that. They range throughout Eastern North America as well as southern Wyoming. They are attracted to porch lights as well as other outdoor lights. They are becoming more and more common in urban and suburban areas. The females will emit a powerful pheromone that attracts males from great distances (few miles). Mating typically occurs after midnight and they may stay joined for most of the night and next day. Females usually only mate once, but males will often mate with more than one female. Eggs are laid in a row of two or six eggs on the leaves or stems of the host plant. They will hatch in about 10 days to two weeks. Their very first meal will be their own eggshell. Apparently this eggshell contains nutrients that are beneficial to them. They are born black and bristly. As they grow and molt they will change appearance and become bright green with blue, yellow, and red knobs. They are as gorgeous in the caterpillar stage as they are in the adult stage. They have a wide variety of host plants, although Maple trees seem to be the preferred host. You may also find them on Alder, Ash, Birch, Beech, Willow, Box-elder, Cherry, Dogwood, Elm, Gooseberry, Plum and Poplar. The adults do not feed. All of the nutrients they need are consumed in the caterpillar stage.

(Photo by: Linda Murphy)

 The caterpillars are often preyed upon by tachinid flies. The fly will approach a caterpillar and land on top of it, she will then deposit her eggs on the sides of the caterpillar. The eggs hatch and the young burrow into the caterpillar and feed from within. When the flies are ready to pupate they send out a chemical that signals to the caterpillar to pupate. The flies will develop within the cocoon and the caterpillar perishes. This constant parasitism by the flies may be causing a decline in the number of these moths. Cecropia's are nocturnal and are rarely seen during the day.

 I placed her in a large bird cage near the timber on our property. I was hoping she would attract a mate. Nothing happened the first night, and the temperatures were somewhat chilly outside so that may have been why. Last night our forecast was for severe storms so I released her from the cage. I did not want her to drown or get water soaked in the cage and not be able to find shelter. I hope she goes on to mate and lay many eggs and populate our timber with more of these beautiful giant moths.


  1. SERIOUSLY that is the MOST amazing CREATURE and I'm SO glad you got pics and info and shared. I will have to look back at this multiple times.


  2. beautiful!!!!!!!!!! we have a similar species here on the west coast, sometimes they will sit on my daughters wall where the porch light is, so it's a treat when we do see them :D

  3. My grandmother gave me a coccon attached to a stick when I was abut 9. I left it on my shelves of other collectibles and was amazed what hatched out of the blue flying around my room. My mom had me release it, I feel now just to get it out of the house.

  4. Bio--I know what you mean, I really think they may be my absolute favorite moth. The colors are so striking. I hope she found a mate and populates my timber. I would love to see more of these beauties around here.

    Garlic---Thank you, what is the species called where you live? I am with you, it IS a treat to see these large moths.

    Prairie---Your grandma sounds COOL! I can't think of a better gift than your cocoon. It is always fun to see what emerges. It is kind of like Christmas morning waiting to open those packages to see what they contain.

  5. Ooooh, LOVELY! What great fun to watch the emergence!!!

  6. Thanks Geek, I just wish I would have "Seen" the emergence. Unfortunately I showed up after the poor little girl had came out of her cocoon and fell on the floor. I was so disappointed, I had been watching that cocoon faithfully for weeks for signs of emergence and i missed it!!!!