Tag Archives: Saturniidae

CECROPIA LOVE AMONGST THE LILACS

NORTH AMERICA’S STUNNING AND LARGEST MOTH THE CECROPIA AND WHY THESE GIANT SILK MOTHS ARE THREATENED – PART TWO

See Part One Here

After spending the winter and most of the spring tightly wrapped in their cocoons of spun silk, the first male eclosed on the last day of May. Burly and beautiful, Cecropia Moths emerge with wings patterned in white crescent spots outlined in rust and black, sapphire blue and black eyespots, waves and wiggly lines in soft woodland hues, and a wide tubular body banded and dotted orange, black and white.

It is easy to tell the difference between a male and female because of the male’s spectacular plume- like antennae.

The females were equally as easy to identify because their antennae are comparatively more slender.

Males rely on their superbly oversized antennae to detect the female’s pheromones.

After each Cecropia Moth emerged from its cocoon and their wings had dried, we placed them on the shrubs around our front porch. The males eventually flew off, but the females stayed in one place and usually by morning we would find a pair, or two, mating in our garden.

They stayed coupled together all day long, uncoupling sometime during the evening. We kept two of the females for several days and both rewarded us with dozens of eggs.

I had read it only takes a week or so for the larvae to emerge from their eggs and was beginning to think ours were not viable, when they began hatching today! In actuality it really took between two and three weeks for the caterpillars to emerge. Possibly the cooler temperatures during this period slowed hatching. The caterpillars are teeny tiny, perhaps one quarter of an inch, black with pokey spines. Charlotte and I collected a bunch of Chokecherry (Prunus viginiana) branches this morning as we prepare to raise another batch of stunning Cecropias.

The adults, both male and female, are short lived. Giant Silk Moths, which include Luna, Polyphemus, Promethea, and Cecropia emerge without mouthparts and cannot eat. Cecropia Moths spend several months in the larval stage, most of their lives as a cocoon, and only a week or two as their beautiful winged adult selves. Giant Silk Moths live only to reproduce.

Threats to Giant Silk Moths are significant. The number one threat is Compsilura concinnata, a tachinid fly that was introduced to North America to control invasive European Gypsy Moths. Both insects are a cautionary tale of why not to introduce invasive species without knowing the full breadth of the harm they will cause. Spraying trees with toxic pesticides that kills both the caterpillars and the cocoons is also a major threat. And, too, squirrels eat the cocoons

Hyalophora cecropia moths are univoltine, having only one generation per year. Our Cecropias began hatching just before the full moon. I have more cocoons and am wondering if this next batch of moths are waiting to emerge prior to July’s full moon.

 

 

NORTH AMERICA’S STUNNING AND LARGEST MOTH THE CECROPIA AND WHY THESE GIANT SILK MOTHS ARE THREATENED – PART ONE

Last summer my friend Christine gave me a handful of Cecropia Moth eggs. Nearly all hatched and grew, AND grew, AND GREW. The caterpillars were a whopping five inches in length and the width of a very large man’s thumb before they began to pupate (become a cocoon).

Cecropia Moth Eggs

First Instar

Second and Fourth Instar

Third Instar

Fifth and Final Stage

Cecropia Going Pooh (Frass)

The Cecropia caterpillar eats the leaves of many trees and shrubs, including alder, ash, birch, box elder, Chokecherry, elm, lilac, maple, poplar, Prunus and Ribes species, and willow. People are always a bit dismayed when I tell them that the adult is born without mouthparts and cannot eat during its brief lifespan. The adult’s only purpose in life is to mate and it lives for about a week or so.

We fed our Cecropia caterpillars Chokecherry (Prunus viginiana), because I knew of a good source where it was growing plentifully.

Cecropia Spinning a Cocoon -The caterpillar pulled some leaves loosely around, but mostly the cocoon is made from its own spun silk. Some spin their cocoons on tree branches and some on the sides of the buildings.

All winter the cocoons lived in glass terrariums on the side of our front porch, which is not enclosed, and which is also out of direct sunlight. The cocoons need to experience normal fluctuations in temperature so that adults will emerge at the correct time of year, when trees are leafed out.

Cecropia Moths are the largest moths found in North America. They are members of the Family Saturniidae. There are approximately 1,500 species of large moths in this family and they are found all over the world. The very largest are found in the tropics, but the wingspan of our Cecropia Moths can reach an amazing 7 inches across (compared to a Monarch, with a wing span of approximately 3.5 inches).

Part Two – emerging, reproduction, laying eggs of the next generation, and how we can help this increasingly rare species.

 

Cecropia Moths are found east of the Rocky Mountains, in Canada and the United States

 

 

 

Mothra!

Cecropia Moth caterpillar copyright Kim SmithNoticeably growing larger day by day, the biggest caterpillar of our batch of Cecropia Moth caterpillars (nicknamed Mothra) still has a ways to go before he/she pupates and becomes a cocoon for the winter.

The colorful protuberances with black spikes are thought to mimic either a poisonous plant or animal and are a defense against predators. Like most caterpillars, the Cecropia moth caterpillar has five pairs of prolegs. The green prolegs are blue at the base with a row of microscopic hooks, or crochets, that enable walking and clinging.

Cecropia Moth caterpillar close up feet copyright Kim Smith

Although the Cecropia Moth has the largest wingspan of any moth found in North America, its caterpillar is not the largest caterpillar. That honor goes to the caterpillar of the Royal Walnut Moth, also called Regal Moth, which in its caterpillar stage is called the Hickory Horned Devil.

cecropia-moth-male-copyright-kim-smithAdult Male Cecropia Moth

Thank you again to friend Christine for the Cecropia Moth eggs. The eggs that she gave me are the offspring of the male Cecropia Moth that she is holding in the photo above.

Update on Giant Silk Moth Cocoon

No exciting news yet to report on our Giant Silk Moth Cocoon. The leaves of the American Birch Tree are unfurling, but no movement within the cocoon.

Giant Silk Moth Cocoon

I am so excited to tell you about this wonderful find. I was walking my pooch Rosie on our usual route down to the harbor and, dangling at eye level from a tree that I have passed a hundred times this winter , there was this structure. Thinking it was what it is, I ran home and checked my Lepidoptera books, and it is the cocoon of a member of the Giant Silk Moth Family, Saturniidaee (not to be confused with the oriental silk moth, Bombyx mori, from which silk fabric is spun).

 Hanging from the tip of the American White Birch branch you could easily mistake it for a dry withered leaf, and that is exactly what the caterpillar has done, weaving the leaf around itself to pupate within. The cocoon is quite a good size, approximately two inches in length by one inch in width. The caterpillar pupates during the summer, overwinters in the cocoon stage, then emerges sometime in May or June. Giant Silk Moths live only for about a week. They mate soon after eclosing and then perish. Giant Silk Moths do not have mouth parts; all eating is done during the caterpillar stage.

Giant Silk Moth Cocoon

Several members of the Giant Silk Moth family of caterpillars eat birch leaves.  I am hoping (and it looks a great deal like) it is the cocoon of the simply stunning Luna Moth, however it could also be the beautiful Polyphemus Moth.

Luna Moth ~ Images courtesy Google

Polyphemus Moth ~ Image courtesy wiki