Trail of Eggs

Sightings Wane

This is the time of year when very few adult monarch butterflies are alive. As the monarchs from Mexico fade away, we’re waiting for the next generation to come out in full force. A surge in sightings will occur when the new adult butterflies emerge and migrate northward.

Eggs Across the Landscape

Monarchs are leaving a trail of eggs as they travel. The migration map shows where eggs of the next generation have been laid. High quality habitat is critical for monarchs at this stage of the annual cycle. It’s interesting that the monarch population is at its smallest every year around Earth Day - a timely reminder to preserve habitat.

How Many Eggs?

After a single mating, a female can lay eggs throughout her lifetime. Each butterfly lays hundreds of eggs — as many as 700 have been counted. Because she dedicates her energies to egg-laying, the female only lives a few weeks during this stage of her life.

Females are in urgent pursuit of milkweed now. People reported monarch eggs on milkweed at all stages of growth, from newly-emerged plants to tender flower buds.

From Egg to Butterfly

It takes about one month for an egg to become an adult. However, timing varies greatly depending upon temperature. The life cycle is slowed by the cold. For example, a difference of only 10°F adds 15 days to development time as shown on the life cycle chart.

Let’s see how long the lull continues before the next generation bursts onto the scene….