Pinning Moths with Students

When it comes to engaging students in insect science, pinning can be the most daunting step, especially when you're working with younger students. The thought of a room full of kids with sharp needles is scary. But in all the times I've pinned with kids, I've been shocked at the results. In truth, I've found that those little hands are quite adept at manuvering the pins around the wings.

Below I outline the steps that I walk kids through, and while these tips are written for early secondary students I think these steps are appropriate for any age group. This handout can be printed and used as a visual guide for students while they're pinning, but I would still provide some level of instruction.

1. Saftey First. It's always good to get this step out of the way right off the bat and set the tone for your activity. You want your students to have fun, but you also want to avoid students using each other as pin cushions.

   • Be clear about expectations

   • Give students an appropriate number of pins

   • Define clear expectations and stick to those

     
     

     

     
     

2. Handle the dead moths. Your kids are going to need to manipulate their specimen, so you'll need decide if students should have forceps (tweazers), or gloves, or just bare hands. Getting students over this initial "ick" will allow your students to get into the pinning.

   • This may be a good entry point to conversations about the ethics of capturing, killing, and perserving specimen.

   • If kids are uncomfortable jumping in with real moths, you can use maniuplative models like the 3D printed moth training tools or paper practice moths.

     
     

     

     Some kids prefer forceps to avoid having to touch specimen.

     
     

3. Provide the necessary materials. Students will need pins and a pinning board.

   • Insect pins can be purchased on amazon and come in stainless spring steel or black enamel, these pins are created to not rust. Pins also come in a variety of sizes, #00 being very fine and #5 being thicker.

   • I prefer #1 pins as they are thick enough to hold easily but not too thick to tear clumsy holes in wings.

   • In a pinch, satin needles can be purchased from any craft store. These are easy to source and have large colored heads, but the metal will eventually rust and they tend to be a little larger than is ideal.

   • Pinning boards can be purchased online, but in my experience the wooden ones typically used by entomologists are expensive and hard to push pins into. I usually have students create their own pinning boards with styrofoam. A small block of styrofoam works well without any modification, but you'll sacrifice perfectly straight wings in your dried specimen.

4. Pin the thorax. The first pin will get pushed through the thorax. Professional pinning guides will instruct you to push the pin directly down through the thorax, slightly to the right of the midline. In my opinion, this specification can be foregone. Instead, focus on making sure your students pin straight down through the thorax so the head of the pin comes out directly in the middle of all six legs. This will keep the moth centered when they start to pin the wings.

   
   

   

   A top down view, with a single pin through the thorax.

   

   Pin your moth directly through the thorax, and pin it to your pinning board.

   
   
   
   

5. Forewing first. Professional guidelines for pinning moths and butterflies typically suggest using wax paper strips to hold the wings in the desired positions, but I've found that having students place a single pin through each wing reduces the number of pins required and makes the whole process less complex. You begin this by using a single pin to pull one forewing forward using the hardened vein at the front edge. Push the wing forward until the trailing edge of that forewing creates a 90° angle with the body. Once in the desired position, push the pin through the wing into the styrofoam.

   
   

   

   Use the hard front of the forewing to drag the wing into this position.

   
   

6. Hindwing next. Using the same strategy as before, you'll use the harder front portion of the hindwing to drag the hindwing until it's fully exposed. When positioned correctly, push the pin through to hold the hindwing in the correct position.

   
   

   

   Using the hard front of the hindwing, drag this wing into the correct position.

   
   

7. Now the other side. Repeat these steps for the other side of the moth, trying to create a symmetry along the midline of the moth. Always starting with the forewing before the hindwing.

   
   

   

   Only five pins are required to fully spread and pin a moth with this method.

   
   

8. Leave it. Leave your pinned specimen in a cool, dry place out of direct sunlight to dry. As the exoskeleton of the moth dries, the joints will stay in their pinned positions. If you pull a pin out and the wings begin to return to their natural position, your specimen needs to dry longer.

   • Leaving specimen in sunlight will cause them to lose their color over time.

     
     

     

     Group specimen up to conserve space.

     
     

Other Considerations:

• Professional pinning and spreading guides will specify the height at which moths should be placed on their first pin, and to do this pinning blocks are used. This is another specific that I forego for kids, but for those interested I print pinning blocks on my 3D printer. The highest step is for the insect, the middle step for the location label, and the lowest step for the identifiaction lable. When used properly, a collection should have all specimen and labels at the uniform heights. This is even harder to do when using a styrofoam block instead of a pinning board with a groove.