The Science of Autumn: What Makes Connecticut’s Leaves So Vibrant

Why Do Leaves Change Color?

For my money, there aren’t many places—or times—like fall in Connecticut. The changing leaves turn the whole state into a series of eye-popping vistas, and the only limit is how far you can see. But that got me wondering: what actually makes the leaves change color?

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When I get stuck on a question like this, I turn to our friend Jen the Zookeeper. She’s the I-95 Morning Show’s wildlife correspondent and always ready to help us understand the world around us. So, I asked her if she knew the science behind the fall colors. Here’s what she had to say:

"Here’s the scoop! Leaves are green during summer because they’re busy making food with a superhero called chlorophyll. But when fall rolls in, the days get shorter and cooler, and leaves basically say, “Okay, we’re done working!” They stop making food and let chlorophyll take a vacation.

With chlorophyll gone, other pigments—like the yellows, oranges, and reds—finally get their chance to shine. It’s like the leaves are showing off their hidden wardrobe before winter puts them to bed. So next time you see those bright fall colors, just remember leaves are having their last big fashion show before winter hits the runway! Got it? Great. Now leaf me alone!" 

Eye popping!

Read More: The Worst Bathrooms in the Nation? Connecticut Made the List 

More on Jen the Zookeeper 

Jen has dedicated more than 30 years to the fields of conservation and science education. As Director of Animal Care at The New Canaan Nature Center in Connecticut, she managed the care of native wildlife and birds of prey while teaching the community about the important roles these wild neighbors play in the ecosystem.

Her career has also included time at both the Bronx Zoo and the Los Angeles Zoo, where she specialized in the care of exotic hoof stock and educated the public on the delicate balance between humans and natural habitats. Later, while working at a wildlife sanctuary in Half Moon Bay, California, Jen oversaw the training and handling of more than 50 exotic species. There, her primary focus was designing educational programs for diverse audiences, including at-risk and foster youth. These programs helped vulnerable children build trust, self-worth, and healing connections through interactions with non-releasable wildlife.

Today, Jen is the owner and sole proprietor of Jen Kotkin Pet Care, where she provides personalized care along with mental and physical enrichment for dogs, cats, horses, birds, and more.