Conservation Matters April 2016

The Texas Land, Water and Wildlife Connection

Rebuilding monarch numbers: landowners, agencies and cities pitch-in

By Eva Vigh

Rebuilding monarch numbers: landowners, agencies and cities pitch-in A damaged male monarch butterfly. Photo courtesy of Dr. Craig Wilson.

When spring migration begins, monarch butterflies emerge from their chrysalises by the millions, preparing for the 2,000-mile, multigenerational journey from Mexico to Canada. Migration is critical for the survival of the iconic North American butterfly, known for its bright orange and black markings, but habitat losses have led to a significant population decline in the past two decades.

“There were an estimated one billion monarchs in 1994, and that declined to about 39 million in 2014,” said Dr. Craig Wilson, senior research associate in the Texas A&M University Center for Mathematics and Science Education. “So in 20 years, there has been a great loss in population.”

In response to this decline, the Texas State Soil and Water Conservation Board (TSSWCB) is working in cooperation with 143 soil and water conservation districts in Texas to help restore monarch butterfly habitat and rebuild populations. The project, funded by the National Fish and Wildlife Foundation and the U.S. Department of Agriculture – Natural Resources Conservation Service, will develop habitat enhancement and restoration plans for over 1,600 acres of rural lands as well as install monarch butterfly gardens in public areas. 

Beginning in May, funding for 1- to 30-acre plots will be available to ranchers, farmers and private landowners wishing to bring back native wildflowers along the monarch’s migratory path. Funds will pay $375 per acre to cover the cost of seeds, planting and land maintenance. Schools, businesses and municipalities are also eligible to receive funding to develop monarch butterfly gardens between 100 and 300 square feet.

Another similar project working to help monarchs is the Mayors’ Monarch Pledge, an initiative introduced by the National Wildlife Federation in 2015 to make cities more habitable for monarchs by creating habitat and educating citizens. Mayors who take the pledge must commit to at least three of 25 possible actions the community could take within the next year to help monarch conservation.

Thanks to Wilson’s efforts, the mayors of College Station and Bryan have committed to the pledge to help protect and restore monarch habitat.

Craig Wilson Dr. Craig Wilson, holding a monarch butterfly. Photo courtesy of Dr. Craig Wilson.

College Station Mayor Nancy Berry issued a Monarch Proclamation in February to raise awareness about the monarchs’ decline and officially declare the city’s support in rebuilding its natural habitat, Wilson said.

The city has committed to posting educational information on the butterflies at the future Nature Center at Lick Creek Park, along with a demonstration garden and creation of a “Butterfly Trail” within the park, said David Schmitz, College Station Parks and Recreation director.

“We are currently working with Keep Brazos Beautiful, the Texas A&M University Garden Club and interested individuals to further the education and habitat for the monarch butterflies,” Schmitz said.

The city will possibly host an event for homeowners in the fall on when and how to plant milkweed and wildflower seeds, which are both essential for monarchs, as well as informational presentations at special events such as Earth day.

College Station is also home to a “monarch waystation,” a habitat designed to provide all the necessary resources for monarch migratory success, Schmitz said.

“The goal (of the Mayor’s Monarch Pledge) is to encourage habitats and plant an I-35 corridor (of milkweed), heading north to south, so you’re really creating a flyway with milkweed,” Wilson said.

A large reason for the monarch population plummet, Wilson said, is the conversion of native habitat to farmland, particularly in the Midwest. Agricultural expansion has led to significant destruction of milkweed, which the monarch caterpillars depend on exclusively for food, he said. Milkweed and other wildflowers have coexisted with crops for centuries, Wilson said, but relatively recently developed herbicides kill all plants except those genetically engineered to be herbicide-resistant. The result is less food for monarchs­ — and thus fewer monarchs.

In Texas, the past decade has hit monarchs particularly hard. Recent droughts took a toll by drying out the insect’s eggs, he said. Monarchs who survived the droughts fared little better; wildfires across the state destroyed acres of wildflowers that the butterflies rely on for nectar.

Monarchs that live east of the Rocky Mountains begin their spring migration from Mexico’s Sierra Mountains, northwest of Mexico City, where they spend winter hibernating in large groups on Oyamel fir trees. The canopy of the trees, similar to an umbrella, and the monarchs’ own body heat create a microclimate that keeps them warm.

“Around March 21, a northward migration is triggered,” Wilson said. “They fly down the mountain looking for water, mate and head up through Mexico to Texas.”

The butterflies lay their eggs on milkweed plants and die, so when the larvae hatch they will have an immediate food source. This generation will fly further north to Oklahoma or Kansas, lay their own eggs and die. As the monarchs travel northward, the cycle continues for four generations before reaching the lower reaches of Canada.

It is the fourth-generation monarchs that make the celebrated flight back to Mexico in the late summer and early fall. They live much longer than the others — 9 months, compared to roughly 30 days — and rely on wildflowers for energy. In Mexico, they return to the same forest their great, great grandparents left nearly a year ago and prepare for their own winter hibernation.

Wilson said the official numbers for this year’s monarch populations have yet to be released. It is hoped that the Mayors’ Monarch Pledge will make a difference to future numbers. An optimistic estimate is the numbers may have increased to 150 million; however a late snowstorm, cold winds and a freeze in parts of Mexico could have dampened the results.

“Last year, it grew to about 50 million,” Wilson said, referring to the monarch population. “It was coming back slowly, and then it got hit by two things: the cold and the wet.”

Individuals interested in helping monarch conservation can refer to the Brazos County Master Gardener publication for a list of native flowers to plant for butterflies and birds.

Landowners or organizations can apply for the TSSWCB funding beginning May 2.

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