Monarch Butterflies Have Just Started Their Migration To Illinois

After a snow storm on Monday, followed by frigid weather on Tuesday and Wednesday, it's perfectly okay if you're looking for signs of spring coming our way here in Northern Illinois.

One of the best signs that spring is getting set to show up on the scene involves monarch butterflies and their annual migration north, and that's what's just starting right now.

Each March, monarchs that have spent the winter in the mountains of central Mexico begin making their way into the southern United States. It’s the start of one of the most remarkable journeys in the natural world, and that journey will bring them right here to Illinois and beyond.

Here’s the part that surprises a lot of people (including me, the guy that just learned this 5 minutes ago): the butterflies leaving Mexico right now won’t be the same ones you’ll see in your yard later this spring.

Monarch Butterfly Migration Is More Of A Relay-Race Than A Single Trip

The first wave of butterflies heads north into Texas and surrounding areas, where they lay eggs before dying off. Then, their offspring continue the journey. It typically takes two or even three generations of monarchs before they finally reach northern states like Illinois.

So when can you expect to see them?

In warmer years, the first monarchs can show up in Illinois as early as mid-to-late April. More commonly, though, sightings begin to increase in May, with the most consistent arrivals happening in late May or early June.

Once they arrive, they’ll spend the summer here feeding and reproducing before a later generation makes the incredible return trip back to Mexico in the fall.

If you’d like to attract monarchs to your yard when they do arrive, planting milkweed is one of the best things you can do. It’s the only plant where monarchs lay their eggs, making it essential to their survival.

So even if it doesn’t feel like spring just yet, nature is already on the move, and the monarchs are on the way.