Raising Lunas: Cocoons

Once Luna caterpillars make their cocoons, the waiting starts (Hint: it always takes them longer to emerge than you want them too).

Like all moths/butterflies, Lunas emerge with fat bodies and small, crumpled wings. Once they emerge, they pump fluid from their bodies into the wings. They need space to do that.

If a cocoon is hanging from a branch, that will be fine. You can also put cocoons at the bottom of a cage or other enclosure, as long as there’s something for the Lunas to climb when they emerge. If they’re in a net cage, the net will work. If it’s somewhere with slicker sides, add a stick or two.

Lunas can be pretty active inside their cocoons – even when they’re hibernating. If you hear them rustling around periodically, that’s just what they do. It’s also fine if you don’t hear them rustle – like babies, some are more active than others.

You’ll know they’re on their way out when you hear a steadier, more purposeful rasping sound. They’re using a sort of tooth to cut their way out of the cocoon. It takes a while.

Once emerged, they’ll start expanding their wings. It takes about 30 minutes for the wings to fully expand, and a couple of hours for them to dry.

If your Luna has thin antennae and a rotund, goddess-like body, she’s a female full of eggs. (thanks to Ann Doss Helms for the photo).

Lunas with larger, more feathery antennae are males.

The crazy thing about big silk moths like Lunas and Cecropias – they don’t eat as adults. They don’t even have mouths. They have one goal – to mate and lay eggs.

If your Luna emerges in the morning, as they often do, you can release it that evening, after the birds have gone to bed (they make delicious bird snacks). Or you can wait until the next evening. Since your Luna doesn’t eat, it won’t get hungry. But regardless of what you do, it will only live about a week.

When you release a Luna it will sometimes excrete a milky fluid and/or fall down to the ground and start flopping around. Both these things are normal defensive mechanisms. It will fly off soon enough.