The monarch butterfly is probably the most popular and best recognized butterfly in North America. It is bright orange and black with white spots on the head and wing margins. Our meadows and shaded trails are full of monarchs these days, and I often see them feeding on the blue sage wildflowers.
The butterflies are migrating south and laying their eggs on milkweed plants, the host plant for the caterpillar. The caterpillar is identified by its yellow, white and black bands and the paired black filaments on the head and tail. While feeding on milkweed, the caterpillar ingests toxins (cardiac glycosides) that make it and the butterfly distasteful to predators such as birds. Monarchs have evolved a way to neutralize the toxins that would kill other insects.
The butterflies are heading to their wintering grounds in the mountainous forests of Central Mexico. Butterflies that are migrating now are not the ones we saw in the spring. They are fourth-generation butterflies.
Back in the spring, the butterflies that left their wintering grounds in Mexico travelled thousands of miles throughout North America to as far as Canada. As they moved north, the first-generation butterflies laid eggs on milkweed plants. After hatching and becoming butterflies, the second generation continued north, repeating the process to produce third and fourth-generation butterflies. The fourth-generation butterflies are the ones we now see migrating south.
The number of monarch butterflies has dramatically decreased in recent years. More than 90% of the monarchs in North America have disappeared in the last 20 years. Causes are loss of habitat and the use of herbicides, which kill milkweeds, the caterpillar’s only source of food.
To save the monarch from extinction, ranchers and farmers need to understand the threat of using herbicides on their properties. County governments should eliminate roadside spraying with herbicides.
I contacted our Tulsa County Commissioner and asked if the roadside spraying in our area could be stopped and explained why. He agreed, and we no longer have spraying along our mile of Lewis Avenue. Others should request the same. Additionally, homeowners could plant more milkweeds in their gardens.
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Frequently Asked Questions about the Monarch Butterfly
1. What do Monarch butterflies eat?
Monarch butterflies primarily feed on nectar from various flowering plants. While they are known for their association with milkweed, adult butterflies also enjoy nectar from flowers such as asters, zinnias, and goldenrods. Milkweed is essential for their larvae since it serves as the sole food source for caterpillars [https://www.monarchwatch.org/read/faq4.htm]
2. What is the life cycle of a Monarch butterfly?
The life cycle of a Monarch butterfly consists of four stages: egg, larva (caterpillar), pupa (chrysalis), and adult butterfly. Monarchs can produce up to four generations in a single summer, with the first three generations living for about 2 to 6 weeks each. The fourth generation, which migrates, can live up to several months.
3. How far do Monarchs migrate?
Monarch butterflies are known for their remarkable migration journey. Some individuals travel over 3,000 miles from their breeding grounds in North America to wintering sites in Mexico. This migration is a multi-generational journey, as not all Monarchs make the round trip.
4. When do Monarchs mate?
Monarchs typically mate in late summer or early fall before their migration. Mating occurs shortly after the butterflies emerge from their pupae, and females can lay thousands of eggs during their lifetime.
5. How can I attract Monarchs to my garden?
To attract Monarchs, plant a variety of native milkweeds suitable for your region, as these are crucial for egg-laying and caterpillar development. Additionally, include nectar-rich flowers in your garden to provide food for adult butterflies. Ensure that these plants are placed in sunny locations sheltered from strong winds.
6. What threats do Monarch butterflies face?
Monarchs face several threats including habitat loss due to agricultural practices and urban development, climate change affecting their migratory patterns, and predation by various insects and birds. Conservation efforts focus on protecting their habitats and promoting the planting of milkweed and nectar plants.
7. How do I raise Monarch butterflies?
Raising Monarch butterflies involves providing a suitable habitat that includes milkweed for caterpillars and nectar sources for adults. It’s important to monitor for pests and diseases that could harm the larvae or adults. Many resources offer guidance on successfully raising and releasing Monarchs into the wild.
These FAQs provide a comprehensive overview of important aspects related to Monarch butterflies, their life cycle, migration patterns, conservation needs, and how to support them in your own garden.