By Teresa Dybvig

We almost missed the stunning sight — hundreds of monarch butterflies in one place at our very own West Meadow Beach, or to be more precise, the West Meadow Wetlands Reserve.

 If you have walked along the beach recently, you’ve probably noticed the field of seaside goldenrod (Solidago sempervirens) lighting up the edge of the dunes all the way down the beach. 

On Thursday, Oct. 4, my husband and I happened to turn away from the water to gaze at the goldenrod glowing in the late daylight. As we approached, we saw hundreds — probably thousands — of buzzing bees and wasps on the flowers. Then we saw a flash of orange, then another, and another. To our astonishment, everywhere we looked, we could see up to 10 monarch butterflies without turning our heads!

We returned on Sunday with a camera and more time. Walking steadily down about a third of the beach, we counted 144 monarchs! I’m sure there were many more; the field is so deep we couldn’t see every flower, and when monarchs fold their wings to eat, they are as thin as a blade of grass from the front. And we didn’t even get to two-thirds of the field. I’m not exaggerating when I say there were, literally, hundreds of monarchs on the beach that day.

 If you have ever seen a monarch butterfly, you know it is gorgeous. It also has a jaw-dropping multigenerational migratory life cycle. The monarchs feasting on the goldenrods at West Meadow are fueling up to fly 2,700 miles to Mexico, at an average rate of 25 to 30 miles per day. Some have already traveled great distances to get here. 

This generation of monarchs is sometimes called the “supermonarch” because it’s the only generation strong enough to make the trip, overwinter on a cool, damp Mexican mountaintop, and fly north again to lay eggs in the earliest-growing milkweed in the southern U.S. before its life comes to an end. The eggs laid by the supermonarchs will grow into monarchs who will fly north and repeat the process, living only two to five weeks. 

The next supermonarchs are the offspring of the offspring of the previous generation of supermonarchs. Sometimes they are the offspring of the offspring of the offspring. So no monarch flying to Mexico has ever made the trip before. Yet thousands of generations have made the journey. 

 Our eastern monarch butterfly, Danaus plexippus is in a heartbreakingly steep and dangerous decline. For every 10 monarchs in the sky two decades ago, there are now only two. Researchers estimate that this species could be extinct within 20 years. If the monarch ceases to exist, we humans will have been the cause.  

Monarchs are in danger because of human activities. We have cut down the trees monarchs require to overwinter in Mexico, we have killed milkweed that is critical for monarch caterpillars by spraying fields and their peripheries with herbicides like Round-up, we have paved over land where monarchs used to fuel up on nectar for their spectacular fall migration to Mexico, and we have contributed to changes in weather that can render the monarch’s route dangerous.

 But we humans have also been working to help the monarch stay in the skies. People in Mexico are growing trees to replace the ones that were cut. Government agencies and ordinary citizens in the U.S. and Canada are planting milkweed in reserves and home gardens.  And we are planting more fall-blooming native plants to fuel the long migration to Mexico.

 This is where West Meadow Wetlands Reserve comes in! The seaside goldenrod there is one of the primary foods for monarchs migrating south. The wildflower’s blooming season is relatively short, so if you want to see the miracle in action, keep a lookout next fall in late September and early October. 

Walk past the left end of the swimming area until you see the shining field of yellow flowers. Stand facing it for about a minute, and you will see a flash of orange, then another, and another. “We did this,” you can say to yourself. Our community. We set aside land for these flowers to grow, and they are helping these amazing creatures stay in the sky.

The author is a resident of Stony Brook.