Milkweed Key to Monarch Butterfly Survival

Milkweed is a precious thing to Sandy Hook resident Sandy Schill. She has gone so far as to rope off a barrier around the patch near her mailbox so that it doesn't fall prey to the town mower.

Schill raises monarch caterpillars, and cultivating milkweed ensures the insects have enough food to survive and complete their lifecycle, including the metamorphosis to butterfly in anticipation of a long journey south.

"It's a lot of work," she said. "I sometimes go up to the mailbox twice a day to provide enough food for them. They're eating machines."

Monarchs cannot survive the long cold Connecticut winters so the black and orange butterflies fly south to the central mountains of Mexico every year, a trek that may take more than 3,000 miles.

In Connecticut, this is the peak period –  between  last Wednesday and next Monday – for the annual autumn migration of monarch butterflies.

While the journey carries with it many perils, the greatest threat to their survival is the destruction of habitat, according to scientists. Logging and land clearing destroy nesting sites and cause changes in weather patterns that leave the butterflies vulnerable to the elements.

Habitats also are destroyed when land is gobbled up for expansion of agricultural acreage and housing developments. Farm and home use of herbicides and pesticides present yet another threat, according to scientists.

About six years ago, a casual conversation with a neighbor by the infamous milkweed patch started Schill on her own journey from monarch hobbyist to conservationist.

As a hobbyist, Schill has found working with monarchs to be a positive experience for her family.

"It's a good reason to get my daughter outdoors," Schill said of her 11-year old daughter Amelia, a 6th grader at Reed Intermediate School who shares the same interest in the butterflies. "Amelia loves to catch them."

A butterfly net on a bamboo pole propped near the kitchen table stands ready for use.

"We've caught them at Sandy Hook School, at Bent of the River (Audubon Society in Southbury) and in our own garden," Schill said.

Their garden features purple coneflowers (echinacea), black-eyed Susans (rudbeckia) and butterfly bushes, all popular food sources for the butterflies.

A census of Schill's own monarch population revealed one adult, six hanging chrysalises and three caterpillars. While two of the plump black, white and yellow striped caterpillars munched on milkweed leaves on the bottom of the cage, another had attached himself to the top of the domed butterfly habitat in preparation for the pupal stage.

"That one is going to go anytime now," said Schill, referring to the distinctive "J" shape of the hanging caterpillar's body which, in her experience, precedes the transformation into the pale green chrysalis.

So far this year, she has tagged and released 14 monarchs. Tagging provides valuable information on migratory pathways, the effect of weather patterns on the insects and survival rates.

A recovered tagged monarch nets $5 to the finder and the tag information is logged into the online database at Monarch Watch, an educational outreach program based at the University of Kansas.

Monarch Watch also issues kits Schill purchases, which contain the tags, a log sheet and instructions.  She then submits her data to the Monarch Watch website.

Schill has a technique for tagging the butterflies.

"You just grab the forewing," she said as she delicately grasped the wings between  a thumb and third-finger while resting the butterfly's hair-thin black legs on her index finger. "I've found they won't struggle if their feet are touching something."

Schill then tenderly applied the tiny adhesive tag with a toothpick, gently pressing it on and rolling the toothpick away.

In the end, all the work is worth it for Schill. She and Amelia watched in awe as the pendulous "J-shaped" caterpillar that was ready to go anytime, suddenly began its transformation into a chrysalis.

"That is freaky!" exclaimed Amelia.

Schill said it's a common misconception that monarchs spin their chrysalis.

"It actually comes from underneath their skin," she said.

For anyone interested in exploring the hobby and finding monarchs to raise, milkweed leaves are a good starting point.

"Check the undersides of milkweed leaves for eggs or caterpillars," Schill said, adding that leaves missing large areas are telltale signs of hungry insects. "You can tell when a leaf's had a caterpillar on it."

Anyone interested in seeing the migration and monarch tagging in action, check out the Lighthouse Point Park Migration Festival on September 26 in New Haven.

And most importantly, Schill advises, don't cut down your milkweed.