How To Tell If A Monarch Butterfly Is Male or Female?

how to see if a monarch butterfly is male boy or female girl. Butterflies on a yellow lantana plant.

Monarch butterflies are beautiful creatures and though they all look similar with their vibrant bright orange wings and black veining, there are little details that you can observe to determine if a Monarch is male or female. Here are three specific features to look out for when determining the gender of the Monarch butterfly:

Size: 

Like people, monarch butterflies come in many different sizes. The size of which the butterfly will become will generally stem from the size when they are caterpillars. Some caterpillars appear far too small, while others stuff their little faces with milkweed until they are ready to become chrysalis and then to a butterfly. 

Males in general are slightly larger  than females. Though size can be an indicator of gender, it is not a fully accurate source to determine the gender. At Paradise Monarchs, we’ve seen both giant male and female butterflies, and also times where males are noticeably smaller than females. So if sizing doesn’t give a 100% accuracy on the gender of the butterfly, how can one tell if Monarch males and females apart? The answer is the next three particulars to look out for.

Veins:

If you compare the wings of the female and male monarch side by side, you will notice that the veins on the females’ wings are notably broader and thicker than the ones adorn on the males’ wings. These thicker wing veins make for a darker appearance for the female than the male. 

Though this is an easy trait to recognize, it can sometimes be difficult to get two monarchs to be cooperative in spreading their wings side by side to let you get a close-up view. They rather be flapping their wings and enjoying their flight. 

Colors:

The color of the wings can also help determine if a Monarch is male or female. As mentioned above, the veins in the female monarchs can make it appear darker, however, the actual color hue of the wings do differ between the gender of the butterfly. 

Males generally tend to be brighter in color in comparison, and have lower hues, which result in a deeper and more red-colored wings. On the other hand, females tend to have higher hues, which result in more orange to yellow colored wings. 

Black Spot:

For male Monarch butterflies, you will see a distinct black spot on each of their lower hindwing, called a stigmata. Female monarch butterflies do not have these spots. These spots are scent glands that help male monarch butterflies attract their female companions. 

This is by far the easiest trait to recognize if the butterfly is male or female. Most of the time, you should be able to see part of the male monarch’s stigmata bleed from the outside to the inside wing.

how to see if a monarch butterfly is male boy or female girl. This is a male boy monarch butterfly resting.

The best way to get a good look at monarchs is by raising them at home. After adult butterflies eclose (emerge from their chrysalis) they will require a few hours to dry their wings before flight. This will give ample time for you to get up close and personal to examine your butterfly. At Paradise Monarch, we provide all Hawaii/Oahu residents and travelers the chance to experience this through our Live Butterfly Chrysalis Gift Box.

Now that you have learned these three traits, you are now an expert and can determine if the butterfly is male or female if you ever spot one in the wild!