When working with tiny critters, injuries can happen. But you'd be surprised what the most common injury used to be in my breeding tent--before I learned how to prevent it.
Butterflies spend most time clinging to the wall and ceiling of a tent--and most tents have mosquito netting. The mesh cubes used by teachers to hold butterflies have similar material.
Butterflies have two huge claws on each foot--used for clinging to foliage. These claws attach very firmly to netting. When you pull butterflies off netting to transfer or feed them, this can exert s huge force on their legs and claws.
It's astonishing how much force. When I was unaware of the danger, sometimes when I picked up a butterfly, a large object it was clinging to would come along as well.
Understandably, if you pull a butterfly off netting several times a day, eventually the weakest point--the joint of the two claws--will wear out and go slack. Usually both claws on one leg are the first to fail.
This means that the butterfly cannot retract the claws--they always point straight out--so it cannot get a grip on anything. The claws on the front legs are most important: they hold the butterfly in place on a flower or leaf, while the rear legs support its weight.
Slack claws on the front legs are a debilitating injury for females laying eggs. When a female lays an egg, she does some serious acrobatics, clinging to the edge of a leaf with the claws of the front legs, while swinging her abdomen under to lay on the underside of a leaf. She can do this in as little as three seconds!
But with bad claws, she may be unable to lay at all. Over the years, I've had several faithful, hard-working females with claws that won't retract. They want to lay so badly! But they just can't get into position! They keep trying, time and time again! Laying eggs (up to 1400) is what they live for, their main purpose in life.
And I needed her eggs for Monarchs for Kids. In these situations, I help the female. I support her while she gets into position, perhaps with my finger under her abdomen or wing, helping her balance. She gets quite comfortable with this help, and very tame. A bond develops between us. She lays one egg after another while I support her.
Another solution is to put a milkweed leaf on the floor of the breeding tent, propped up at an angle or height that's reachable--whatever works.
How to prevent injury to butterfly claws
Remember, the front claws are the most important to protect.
Entice the butterfly to climb onto a Q-Tip soaked in honey water. They would rather go with the sugar than stay on the mesh. First get the front feet on the Q-Tip, then gradually move it further from the mesh at an angle, so one hind foot disengages, then the other.
If the Q-tip fails, another method is to offer it a piece of smooth paper.
While the butterfly clings to mesh, pinch its wings together but don't lift it away yet. Take a small piece of smooth paper and put it ahead of the front feet. Wait till the butterfly climbs onto the paper, at least with the front feet. Then pull the butterfly by its wings away from the mesh. Then you can safely remove the paper because it can't grip smooth paper very firmly.
Other injuries and their prevention
Butterflies and large caterpillars are more robust than you think. They are pretty hard to injure if you are reasonably careful. Encourage children to handle them, but at the same time respect them.
Butterfly legs are incredibly tough. I've only seen one completely broken leg, like a twig bent at an angle. I don't know how it happened. After a day or two, the part beyond the injury fell off. This male butterfly continued to hang out around my garden and did quite well, because it was a rear leg and he could support his body with the stump, while he held onto flowers with the front legs. Damaged leg joints are more common.
- Drowning. Avoid open containers with water. After it rains, bail out the tent promptly. If you use saucers with water to exclude ants from artificial flowers, use shallow saucers. If you have weak butterflies (something you record on your notes), you need to be more cautious.
- Falling during eclosure. Provide a rough surface (cloth or taped paper towels) they can climb up if they fall.
- Unable to twist during eclosure, space too cramped, leads to deformed wings.
- Breaking a wing. Butterflies have an amazing ability to fly despite severely damaged wings! They can lose most of both hind wings and still fly quite well. They can lose half a front wing and still fly reasonably well. Lose the wing tip? No problem at all. So don't worry if there's minor wing damage. But if the main support "spar" of the front wing is broken so the wing is bent at a sharp angle or dangling, that's a serious problem. These can be repaired, if done promptly before the rest of the wing surface rips. See...
- Butterflies, especially weak ones, can become jammed into tight angles, such as where the walls of the tent meet the floor.
- General caution advised-- don't be a bull in the China shop.
- Handling a butterfly too soon after eclosure. The wings and exoskeleton have to harden. Different parts harden at different speeds. Soon after eclosure, the legs are firm enough to hold them, and they can even climb. But the wings take longer. Give the wings 3 hours at a minimum, before you gently handle them by the wings. Four hours is better. Wait till the next morning before you impose serious stress.
- Dropping a chrysalis. They shatter! Always hold something soft under it if you need to move one.
- Stepping on a wandering caterpillar. If you suspect wanderers, or have large caterpillars about to form the "J," check the floor as you enter the room.
- Escaped butterflies can get trapped between an open window and a screen--hard to remove. Close windows when there's a chance of butterfly escape, or you have eclosures. Look before you sit down.
- Caterpillars drown in jars holding water and milkweed. Alway use jars with lids.
- Molting caterpillars (shedding their skins) are vulnerable. They go inactive for about 24 hours. During this time, it's best not to move or disturb them, because they may be attached to the leaf or stalk by silk. But if you have to, it won't be fatal.
- Caterpillars about to form the "J" are spinning a disk of silk. The silk may be invisible to you, but they have put a lot of work and silk into it. They have limited silk, so best not to disturb if you can avoid it. While you can't see the silk pad, you can see a tiny white knot of silk under their chin as a sign that spinning is underway, the "J" is on the way.