If you've ever handled a butterfly, you probably noticed the powdery residue left behind on your fingers. A butterfly's wings are covered with scales, which can rub off on your fingertips if you touch them. Will losing some of these scales prevent a butterfly from flying, or worse, will a butterfly die if you touch its wings?
Butterfly Wings Aren't as Fragile as They Look
The idea that merely touching a butterfly's wings may prevent it from flying is more fiction than fact. Although their wings appear fragile, consider the following butterfly flight records as evidence of their strong construction:
- The longest documented flight by a migrating monarch butterfly was 2,750 miles, from Grand Manan Island, Canada to the overwintering grounds in Mexico.
- Painted lady butterflies are known to fly even farther, covering 4,000 miles from North Africa to Iceland. Researchers studying the flight of this species using high-speed cameras reported that painted ladies flap their wings an astounding 20 times per second.
- The Paralasa nepalica, a butterfly found only in Nepal, lives and flies at an altitude of nearly 15,000 feet.
If a simple touch could render a butterfly's wings useless, butterflies could never manage such feats.
Butterflies Shed Scales Throughout Their Lives
The truth is, a butterfly sheds scales throughout its lifetime. Butterflies lose scales just by doing the things butterflies do: nectaring, mating, and flying. If you touch a butterfly gently, it will lose some scales, but rarely enough to prevent it from flying.
A butterfly wing is made of a thin membrane webbed with veins. Colorful scales cover the membrane, overlapping like roof shingles. These scales strengthen and stabilize the wings. If a butterfly loses a great number of scales, the underlying membrane may become more prone to rips and tears, which in turn, could affect its ability to fly.
Butterflies cannot regenerate lost scales. On older butterflies, you may notice tiny clear patches on their wings, where scales have been shed. If a large section of scales is missing, you can sometimes see right through the clear membrane.
Wing tears, on the other hand, do affect a butterfly's ability to fly. You should always try to minimize tears to a butterfly's wing when catching them. Always use a proper butterfly net. Never trap a live butterfly in a small jar or other containers in which it may damage its wings by flapping against the hard sides.
How to Hold a Butterfly So You Won't Damage Its Wings
When you handle a butterfly, gently close its wings together. Using a light but firm touch, hold all four wings together and keep your fingers in one place. It's best to hold the wings at a point close to the butterfly's body, to keep it as still as possible. As long as you're gentle and don't handle the butterfly excessively, it will continue to fly when you release it and live out its life cycle no worse for the wear.
- "Insect Flight," Encyclopedia Smithsonian website, Smithsonian Institution. Accessed online June 9, 2015.
- "Frequently Asked Questions," Learn About Butterflies website. Accessed online June 9, 2015.
- "Monarch Tag and Release," Virginia Living Museum website. Accessed online June 9, 2015.
- Gammon, Katharine. "The Mathematical Butterfly: Simulations Provide New Insights On Flight." Inside Science News Service, April 19, 2013. Accessed online June 9, 2015.