CAPE MAY — If you'd like to see those glimmering orange-and-black-winged monarch butterflies flitting about in your yard this autumn, don't even think about yanking that milkweed out of your garden.

In fact, naturalists at the New Jersey Audubon's Nature Center of Cape May would like you to pick up a few milkweed seeds at their first-ever Monarch Festival on Sunday, Oct. 8, and plant even more.

Though milkweed may be the bane of most landscapers and gardeners — who treat it like an invasive species — it is actually a native plant and the single most important food source for monarchs. The butterflies also use the plant as a home and a nursery for their larvae.

The species is currently making its autumn migration of thousands of miles from Canada and the northern and central part of the United States to Florida and Mexico.  The Cape May peninsula is considered among the most important North American flyways for migrating species.

"It may sound kind of crazy, … but the more milkweed the better," said Brendan Schaffer, a teacher-naturalist at the center who will host a "Bug, Bed and Breakfast" during the event.

The Bug B&B will be a how-to that will teach children and adults about cultivating their own monarch habitat — from caterpillars to chrysalis and beyond. And he will talk about little-known milkweed facts, like how it contains a toxic substance that caterpillars eat. To protect themselves, the caterpillars develop an enzyme against the steroid-like substance, cardenolides but become poisonous to their own natural enemies.

Terry Reimink

The festival, from 11 a.m. to 4 p.m. on the center grounds at 1600 Delaware Ave. in Cape May, will also feature crafts, games, workshops, music, wine tasting, a beer garden, and tours of a newly created wildlife meadow habitat. It is expected to attract hundreds of monarch enthusiasts and others.

Schaffer said the inspiration for the festival was the need to inform the public about the plight of the monarch and "stop talking about it and actually do something about it."

The U.S. Fish and Wildlife Service said in early 2015 that nearly a billion monarchs had vanished from overwintering sites since 1990. The government said one of the main reasons is the use of herbicides by farmers and homeowners to kill milkweed. Some researchers also contend that the decline of the eastern monarch population directly correlates to milkweed loss caused by the adoption of herbicide-tolerant, genetically modified corn and soybeans.

Members of the New Jersey Audubon Monarch Monitoring Project — currently in its 26th year — are now in the midst of measuring the current migration's numbers and activities. The monitoring, which began Sept. 1, runs until the end of October, with researchers working daily to track and tally the insects.

"The migration that the monarch butterflies undertake is really one of the great wildlife spectacles of North America," said Mark Garland, director of New Jersey Audubon's monarch project.

"We also know that as the monarch goes, so go other species. The monarch is no doubt something of a 'canary in the coal mine' when it comes to insect health, … so we carefully track their health," Garland said.

The group has tracked individual monarchs over the years by placing tiny adhesive tags on their wings that give researchers a long-term data set and critical insights into the direction and speed of migration. In 2016, New Jersey researchers tagged 3,592 of the butterflies, most of them at Cape May Point. Since the project began, Audubon staffers have recovered about 70 of the tagged butterflies in Mexico.

Garland said that relatively small number that were found tagged actually represents hundreds and hundreds of others that survived the lengthy flight. In one of the cases, researchers were fascinated to learn that a butterfly tagged in Cape May traveled hundreds of miles to Georgia in just three days.

More information about the Monarch Festival or the butterfly count may be found on the Nature Center of Cape May's website at njaudubon.org/centers/nccm or by calling 609-427-3045.