Thanks to climate change, New Yorkers are facing more intense storms and a city that will probably look like Atlantis. In the meantime, NYC has been trying to combat street flooding with things like bioswales, a.k.a. those little curbside gardens that capture storm water runoff. Now, those little superstar sidewalk gardens are also oases for butterflies!

The Department of Environment Protection announced yesterday that "monarch butterflies have been found by gardeners in curbside rain gardens built over the last few years in Queens and Brooklyn."

Since the mid-1990’s, the population of monarch butterflies has dropped significantly due to many factors, including severe weather events and a changing climate, the use of pesticides, invasive species and a rapidly shrinking habitat. The curbside rain gardens include hardy plants to help soak up stormwater before it can enter the sewer system and contribute to overflows into local waterways. Milkweed, a favorite of the monarch butterfly, is one of the plants that is regularly included in the rain gardens. With roughly 2,500 rain gardens built over the last few years, and thousands more planned for the coming years, monarch butterflies will have an expanding habitat throughout the five boroughs to both reproduce and feed during their annual migration...

In the New York region, monarch butterflies lay their eggs on three types of milkweed, Common Milkweed (Asclepias syriaca), Butterfly Weed (Asclepias tuberosa) and Swamp Milkweed (Asclepias incarnate), as it is the only food a young caterpillar will eat before it transforms into a chrysalis. The milkweed contains a toxin that once ingested, makes the monarch caterpillars and butterflies distasteful to predators. The purple-flowering milkweed is often planted within the rain gardens because its root system is capable of absorbing large amounts of water. Other insect species that have been found within the rain gardens include ladybugs, praying mantis and honey bees, which are valuable pollinators.

DEP gardeners found monarch butterfly caterpillars and chrysalises within rain gardens in Rego Park, near Queens Boulevard, and in Brownsville, near Atlantic Avenue. The jade and gold chrysalises were closely monitored until the monarch butterflies emerged. This latest generation of monarchs will fly south to Mexico for the winter where it will begin the species’ lifecycle all over again.

"Curbside rain gardens are primarily constructed to help capture stormwater, which is vital to our strategy to continue to improve the health of New York City’s surrounding water bodies," DEP Acting Commissioner Vincent Sapienza said. "However, this exciting finding is also a perfect illustration of how they can serve many other important purposes, including improving air quality and creating beautiful natural habitats throughout the city."

The DEP shared photos (above) and videos (below) of the gardens and the butterflies, even showing them at the caterpillar and chrysalis stages!




"The magic of the monarch butterfly is that little patches of habitat matter. People everywhere can help by protecting and restoring spaces for the butterflies in their communities. Efforts at the local level really make a difference in conserving this species nationally," added Wendi Weber, northeast regional director for the U.S. Fish and Wildlife Service.

Here's a map of the gardens and other DEP "green" infrastructure; about 2,500 rain gardens have been built and "thousands more" are on the way, according to the DEP.