Little Known Shocking Fact About Silk Moths

Did you know that many silk moths do not have a mouth and no other means of taking in nutrition?

Strange are the laws of nature. It was a big shock to the Muezart team to hear that the Eri Silk Moths do not have mouthparts and so live only up to 5-10 days after emerging from their cocoon. Not just Eri silk moths, but many more varieties too do not have mouthparts.

Eri silk is known as peace silk or ahimsa silk, where the silk moths can naturally come out of the cocoon before the silk is spun. This process, of an open-ended cocoon, is unique to Eri silk. When the silk moth emerges from the Eri cocoon it lays eggs for reproduction. Not all cocoons are harvested this way. Often the worm is extracted from the cocoon and sold in the village markets as an additional form of income. That is why we don't claim Muezart Eri silk as pure peace silk. 

Mulberry, Muga, and Tussar silk are unlike Eri Silk. The cocoons are created with long filaments and boiled or steamed with the silk moths inside. This process ensures that the outer cocoon made of silk fiber has no breakages.

Mulberry cocoons are hard and regular in size and spun by the caterpillar with a fine continuous thread. The Eri cocoons are soft and irregular in size. The soft fibers allow the moth to emerge from the cocoon.

An Insightful, Valid Question

One of the visitors to our site had an interesting question – if these silk moths are going to die anyways in a few days, what is the big deal of saying that the process of getting Eri silk does not involve killing the moths and that they are allowed to live? It is not like they have a long life to look forward to!

This made us think. We guess nature meant for these moths to have just an extremely short lifespan. By allowing them to emerge from the cocoon and not boiling them alive in their cocoons before they emerge, the silk moths are being allowed to live their full lives! While this thought may cause some to feel better, we have a deeper reason for promoting and making Eri silk.

It is not that Muezart hit upon this way of producing silk. The technique is an age-old one. We chose to support the farmers/households who rear Eri silkworms for their livelihood. The sericulture industry is an opportunity for our own people. We see it as a lost opportunity because our local people have no outlet for the yarn and weaving that can be made with this beautiful Eri silk cocoon. The process of not involving taking life to get silk might feel right, but for us, it is also about the circular sustainable process. For Muezart the process goes beyond the moth living. We know that the worm creates additional income opportunities in the villages of Meghalaya.

Questions About Why So?

A colleague of mine was disturbed the day she came to know that Eri moths do not have a mouth. She had several questions about why so. Many of you may have the very same questions too? We are presenting you with her questions and our answers. These answers are based on our in-house Eri silk farming experience, and what we found by researching and talking to experts.

Q & A on The Strange Facts About Silk Moths

Q: Is it typical that all moths don’t have mouths?

A:Yes, most moths don’t have mouths!
All domesticated moths, which are silk moths, have no mouthparts and so have very short lifespans. Even if the mulberry silk moths (Bombyx mori) are allowed to emerge from their cocoons, without killing them by boiling the cocoons in water, the moths will live only for 5 to 10 days. Why? They neither have a mouth to eat with nor a proboscis (like a butterfly does) to suck nectar with!

Even the well-known beautiful Atlas moths (wingspan of more than 10 inches) and the Luna moths (wingspan of 5 to 7 inches and looks like a jet plane) do not have mouthparts and cannot eat once they emerge from their cocoons. These too live for less than a week.

From what we have understood Eri silk moth too does not have a mouth.
All the eating the Eri caterpillars do before they metamorphose into a Eri Silk moth (Ricini moth), is all the nutrition they have to sustain themselves. They live for about 5 days. What is amazing is that the short lifespan is used to mate and propagate. The female moths lay over 300 eggs in their lifetime.

Q: Aren’t there moths that eat clothing made of natural fibers?

A: Yes. These moths have a longer lifespan! Even they do not have mouths. The caterpillars of these moths can live for up to 2 years before transforming into a moth. The harm (of eating the cloth) is done by these hungry caterpillars, not the moths.

Q: Is a short lifespan typical of all moths?

A: Yes. The answer to this as above. All large silk moths have a very short lifespan.

Q: What is the purpose of the moth?

A: Just another link in nature. They come low in the food chain and become food for bats and rodents. They help in the pollination of flowers – but this will be done at night, as they are nocturnal. And, thanks to human ingenuity the silk moths help us get silk cloth for our use.

Q: How are moths different from butterflies?

A: They kind of look the same, but are different:

• Moths keep their wings open, like a plane! Butterflies have their wings closed.
• Butterflies have two antennas that are thin and long while silk moths have short, fuzzy ones
• Moths are nocturnal – they move in the night. Butterflies are seen in the daytime.
• Moths spin cocoons with silky fiber. Butterflies make a shiny pupa.

Q: Do moths fly?

A: Our colleague who has himself learned to rear Eri silkworms said “after laying eggs, the moths start flying – mostly in the evening, but drop down after a few minutes. Within a day of seeing them fly we have seen them dead.”

Researching and finding out more about this strange fact about moths not having a mouth left us feeling sad, at the same time happy. Sad because one cannot imagine a creation of God without any means of sustaining itself. Happy because the moth does what it came to do in the very short time it has on this earth. Is there a message for us mortals?

Follow us as we discover more from the world of Eri silk. Our dream is to see the people who care for this natural cycle thrive so that together we can create and regenerate ancient traditions while we #FlourishTogether