In Haven for Butterflies, Builders Are the Monarchs

Pacific Grove on the Monterey Peninsula bills itself as “Butterfly Town U.S.A.” and takes every opportunity to affiliate with the monarch butterfly. There is a Monarch Dental Group, a Monarch Mobile Home Park and a Monarch Restaurant. There is a Butterfly Grove Inn and Butterfly Trees Lodge.

Large metal butterfly wings adorn the Chamber of Commerce building. And each fall, all the kindergarten pupils dress as butterflies and parade through the town’s main street.

But while tourists continue to flock to Pacific Grove searching for monarchs, the number of butterflies that migrate to the town each fall has decreased sharply. In the last decade, dozens of trees where the butterflies used to gather have been destroyed to make way for development projects.

“When we moved here hundreds of butterflies covered our entire lawn. It was beautiful, a carpet of bright orange and black,” recalled Betty Nixon, who moved to Pacific Grove--a town of 16,000 near Monterey--35 years ago. “But a few days ago I think I counted a total of six butterflies around our house.”

In the 1970s, city officials placed a high priority on development and did not protect butterfly habitats, said Vice Mayor David Eaton. The City Council, at the time, assumed that if the trees where the butterflies gathered were cut down, they would just move to neighboring trees. Instead, many monarchs perished or left the area.

A number of other California communities have destroyed monarch habitats and seen a great decrease in butterflies. In the last three years seven monarch roosting sites have been destroyed in the state to make room for housing tracts, business parks, horse farms and trailer parks, said Chris Nagano, chief entomologist for the Monarch Project, a private conservation group. Although millions of monarchs migrate to California each fall, their existence could be threatened if many more of the approximately 100 West Coast roosting sites are destroyed, Nagano said.

The Los Angeles-based Monarch Project is working to preserve remaining West Coast roosting sites, which are located between Mendocino County and Ensenada, Mexico. Volunteers visit roosts and affix small white tags to the wings of thousands of butterflies, said Nagano, a research associate at the Los Angeles Natural History Museum.

The tags give the address of the museum so people who find dead butterflies in fields and back yards can return the insects to the museum. Others see live butterflies and call the museum after spotting the tag. Nagano can then determine migrating patterns and population trends.

West Coast Sites

The three West Coast sites with the largest concentrations of monarchs are in the Ellwood area of Goleta, Pismo State Beach and Natural Bridges State Beach in Santa Cruz. The wintering site closest to Los Angeles is in Pt. Mugu State Park, along Pacific Coast Highway near the Ventura County Line.

Last year, the Legislature passed a bill recognizing monarchs and their roosting sites as a unique resource in California. But there still is no specific protection plan for the butterflies nor any penalties for the destruction of roosting sites.

Mexico has been much more aggressive than the United States in protecting its monarchs, which migrate from eastern North America to an area outside Mexico City. It has established monarch reserves and instituted laws protecting its migrating butterflies.

American entomologists are concerned about the loss of the winter sites because the monarchs travel such a great distance and their journey is so remarkable. Monarchs migrate to the West Coast each fall from the Central Valley and from as far away as Utah, Nevada and Idaho. They fly thousands of feet above the ground, navigating by the position of the sun, searching for thermal air currents and then effortlessly gliding for miles. Butterflies have traveled up to 80 miles a day, Nagano said, and migrations of up to 4,000 miles have been recorded.

Monarchs would not survive the harsh winters of the inland states so they spend the fall and winter on the West Coast. The monarchs find their favorite groves of trees in California by seeking specific humidity and temperature conditions.

Lay Eggs in Spring

In the spring the butterflies return to the Central Valley or the western slope of the Sierra and lay their eggs on milkweed, the only plant caterpillars feed on. The monarch’s bodies contain enough milkweed--a poisonous substance to birds--to protect them from predators. It is such an effective defense mechanism that other butterflies such as viceroys, which do not feed on milkweed, mimic the monarch’s color pattern as a protective device.

Originally, when monarchs arrived in California for the winter, they roosted almost exclusively in Monterey pines. But about 100 years ago, the eucalyptus was introduced here from Australia and most monarchs now prefer eucalyptus groves.

The Pacific Grove City Council is now more concerned about preserving monarchs, Eaton said, and has required a butterfly habitat study from a property owner who wants to build homes on a roosting site. A group of residents called Friends of the Monarch is trying to persuade the state to buy the property and turn it into a monarch reserve.

“We’re either going to have to do something or we’re going to have to change our name from Butterfly Town U.S.A to something else,” said Carol Arthur, founder of Friends of the Monarch. “Because once these butterflies are gone, they’re gone. They’re not something we can bring back.”

Residents worry, Arthur said, that the butterfly soon will become an empty symbol in Pacific Grove. There are no butterflies left near the Butterfly Trees Lodge, because the adjacent roosting site was destroyed. And the proposed development project is on one of the two remaining sites in town. The Butterfly Grove Inn is adjacent to that site.

In Name Only

“If the project goes through there won’t be any butterflies left near the Butterfly Inn either,” said Vern Yadon, director of the Pacific Grove Museum of Natural History. “All you’d have left of the butterflies would be the name. It would be like having a dinosaur village.”

“Some people think butterflies are frivolous things and don’t take the problems seriously,” Nagano said. “So we talk about how unique their migration is and how vulnerable they are. But what really gets people interested in the butterflies is a visit to their wintering spot. It’s a spectacular sight when you have the opportunity to see great numbers of butterflies in one spot. It’s mystical, surreal and incredibly beautiful.”