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At first glance one might assume the above pictured item is a hummingbird nest. That turns out not be the case, however.
In fact, it is not a nest at all; it is a cocoon left behind by a member of the silkworm moth family. This cocoon was found clinging to a branch of a young Oak tree in the community of Heath. The body measures barely 1.5 inches in length, having a girth comparable to that of the index finger. A connecting strap anchors the cocoon in place. The opening through which the adult moth is introduced to the world is just wide enough to accommodate an English pea.
All silkworm moths go through four stages in their life cycle – egg, larva (caterpillar in this case), pupa and adult.
Because there are 300 different species in the Bombycidae family of moths, giving credit for the handiwork pictured above is somewhat difficult. However, one of three moth species is likely to have called this cocoon home for a short while – Cecropia, Polyphemus or Promethea, all of which populate this part of the south. All three are large moths having wingspans in the range of five or six inches and have been known to spin this type of cocoon during the caterpillar stage as it readies for winter.
Amazingly, the average cocoon is formed when a caterpillar wraps itself in a silk thread that if stretched continuously could reach nearly two miles in length. The process to build the cocoon can take upwards to a week to complete. Once secured inside the protective silk, the caterpillar enters the pupa stage until early spring. At that time it will exit its winter home as a mature adult moth.
The hole in the top of the cocoon is created when the adult moth secretes an enzyme that dissolves the bonding material used to hold the silk thread in place, allowing an escape path. Unfortunately for the moth, its escape procedure renders the silk threads useless for commercial application.
To prevent the moth from damaging the threads during exit, Commercial Chinese silk farmers simply pre-empt the process by submerging the cocoons in boiling water just before the silkworm makes its escape. That process serves two purposes; first, it kills the prisoner moth before it has a chance to do damage to the cocoon, and, secondly, it melts away the bonding saliva, allowing the silk thread’s extraordinary length to remain intact. It is then harvested, being rolled onto spindles. Many strands will then be braided together to make a thread suitable for weaving into fabric as we know it.
Meanwhile, the best time to catch a glimpse of a silkworm moth the likes of Cecropia, Polyphemus or Promethea is during evening hours in the vicinity of a bright light source.
In fact, it is not a nest at all; it is a cocoon left behind by a member of the silkworm moth family. This cocoon was found clinging to a branch of a young Oak tree in the community of Heath. The body measures barely 1.5 inches in length, having a girth comparable to that of the index finger. A connecting strap anchors the cocoon in place. The opening through which the adult moth is introduced to the world is just wide enough to accommodate an English pea.
All silkworm moths go through four stages in their life cycle – egg, larva (caterpillar in this case), pupa and adult.
Because there are 300 different species in the Bombycidae family of moths, giving credit for the handiwork pictured above is somewhat difficult. However, one of three moth species is likely to have called this cocoon home for a short while – Cecropia, Polyphemus or Promethea, all of which populate this part of the south. All three are large moths having wingspans in the range of five or six inches and have been known to spin this type of cocoon during the caterpillar stage as it readies for winter.
Amazingly, the average cocoon is formed when a caterpillar wraps itself in a silk thread that if stretched continuously could reach nearly two miles in length. The process to build the cocoon can take upwards to a week to complete. Once secured inside the protective silk, the caterpillar enters the pupa stage until early spring. At that time it will exit its winter home as a mature adult moth.
The hole in the top of the cocoon is created when the adult moth secretes an enzyme that dissolves the bonding material used to hold the silk thread in place, allowing an escape path. Unfortunately for the moth, its escape procedure renders the silk threads useless for commercial application.
To prevent the moth from damaging the threads during exit, Commercial Chinese silk farmers simply pre-empt the process by submerging the cocoons in boiling water just before the silkworm makes its escape. That process serves two purposes; first, it kills the prisoner moth before it has a chance to do damage to the cocoon, and, secondly, it melts away the bonding saliva, allowing the silk thread’s extraordinary length to remain intact. It is then harvested, being rolled onto spindles. Many strands will then be braided together to make a thread suitable for weaving into fabric as we know it.
Meanwhile, the best time to catch a glimpse of a silkworm moth the likes of Cecropia, Polyphemus or Promethea is during evening hours in the vicinity of a bright light source.
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