Blog

The Monarchs are on their way!

10/6/2021

Last week, Cape May had the one of the largest monarch butterfly flights since 2010. Monarch numbers built up dramatically over the course of a few days with light northwest winds, culminating in a mesmerizing cloud of fluttering wings overhead on Thursday afternoon. The thousands of monarchs we saw funneling through Cape May are on their fall journey south to Mexico, where they will arrive in a few weeks and spend the winter.

Monarchs don’t migrate at night, so when the night is chilly and the sun begins to set they huddle together in giant groups, called roosts, to stay warm. As night fell on Thursday here in Cape May, we saw thousands of monarchs gathered together to roost in the pines by the beaches overlooking the Delaware Bay. We sat and watched for hours as more and more monarchs united, their wings briefly opening to reveal their bright orange patterns each time a new individual clumsily glided in to join the group. Latching on to each other and the pine needles, the monarchs could almost be mistaken for fall foliage. It was truly a wonderful and humbling sight to behold.

On the morning of Friday, October 1st, the sun’s rays gently warmed each sleepy butterfly as light winds blew in from the northwest. This combination of warmth and wind was the perfect opportunity for the monarchs to take on one of the riskiest parts of their journey: crossing the Delaware Bay. Spanning 12.8 miles at its narrowest point, the path between the New Jersey and Delaware coasts provides no stopping points for floundering monarchs, meaning that they must make the journey in a single flight. As the monarchs arose from their sleep and disappeared across the bay on Friday morning, those of us lucky enough to watch the spectacle were blown away and humbled by the tenacity and strength of these little insects. At one point, one of Cape May’s naturalists counted 2,500 monarchs per minute pouring over the dunes!

People always ask when the best time to come to Cape May to see the monarch butterfly migration is, but it is impossible to predict when the next big flight will be. What we do know is that the monarchs will be passing through Cape May for the rest of October as they funnel down to their wintering grounds up in the mountains of Mexico. We hope you’ll stop by to see them!

By Kyra Madunich

photos from Mark Garland

Monarch butterflies are the only butterfly species that completes a two-way migration, traveling from Mexico to as far north as Canada. Imagine an insect weighing less than a paper clip setting out on this amazing and mysterious journey of over 2500 miles, where danger lurks throughout!

Loss of habitat, extreme weather, predators, and toxic pesticides have all taken a toll on fragile populations and the future of Monarchs is at risk. You can make a difference and save Monarch butterflies for future generations.

When you Adopt a Monarch, you support New Jersey Audubon’s efforts to protect this iconic species. Your tax-deductible gift will fund our Monarch Monitoring Project, tagging and monitoring these butterflies for more than three decades, while teaching people how to protect them.

New Jersey Audubon