BLOOMINGTON - Butterflies are endangered at Bloomington's Miller Park Zoo. In the past, butterflies were displayed from Memorial Day through Labor Day. But this summer, zoo visitors can view them only in the month of July.

Zoo director John Tobias cited rising costs and government regulation as causes for the cuts. If the public fails to embrace the reduced schedule, he said he may do away with the exhibit entirely next year.

"We think they are very popular. There are people, I think, who have been waiting to see them, and we are hoping they'll come out and enjoy the experience," Tobias said. "But we're waiting to see how well the one month is perceived to see if we will continue butterflies at all. I need to hear back from visitors."

Tobias thinks maintaining a butterfly presence at the zoo is important to enhance a strong conservation message. Convincing people to save butterfly habitat is easier than selling the notion to save "xyz rat" that may live where butterflies do and benefit when butterfly habitat is spared, he said.

Illinois has about 2,000 species of butterflies and moths, according to the Illinois Department of Natural Resources. They are important economically because they pollinate flowers and because they are food sources for many birds, mammals and other insects.

Doug Taron, curator of biology at the Peggy Notebaert Nature Museum near Lincoln Park in Chicago, is director of the Illinois Butterfly Monitoring Network, a group of volunteers that has done an annual butterfly census since 1987.

Most butterfly populations are doing "just fine," he said, but some specific species are struggling as land use changes. For example, the regal fritillary, which IDNR lists as endangered in the state, relies on prairies that have all but disappeared, Taron said.

The swamp metalmark relies on wetlands in northern Illinois and was extinct in the state until 2001. That's when a restoration project started with help from Taron's nature museum, which has a live indoor butterfly exhibit year-round.

Taron also expects short-term fluctuations in the number of common species like the monarch, which don't do well in years that feature long, cold, wet springs like Illinois experienced this year.

"But we've also seen those populations jump back," he said.

The streamlined schedule at the zoo exhibit became necessary after Tobias learned federal regulations require zoo personnel to be present at all times the exhibit is open to the public. Even though the zoo only receives butterflies native to the United States, the reasoning is to prevent escape of insects that might carry parasites potentially harmful to local agriculture, he said.

"There is apparently a very tiny parasitic wasp that can be in the (butterfly) chrysalis and can escape. We have not ever seen one, but we must follow protocol," he said.

Tobias was told the requirement has been on the books for a while. But enforcement was lax before Sept. 11, 2001. What the connection is between butterflies and terrorists was unclear, he said.

"I didn't ask. I just said, 'Whatever.' "

Because of staffing constraints, Tobias tapped the junior zookeeper program to provide young volunteers willing to baby-sit the exhibit, he said. To make that feasible, the public viewing time was shortened.

The cost of the insects themselves has risen at the same time, he added.

"In the era of tight budgets, we had to cut back on them," he said.

The zoo received its first shipment of 150 butterflies from a Florida breeder 10 days ago. When they arrive, the insects are encased in the hard shells they create to change from caterpillar to butterfly, a process called metamorphosis. Handlers carefully remove them from their packing material and glue them upside down to wooden dowels to simulate the natural setting where they would usually hang under tree branches.

Butterflies emerge three days later and are released into the exhibit, where they live about two weeks. The zoo will receive 100 butterflies each week until the end of July.

The exhibit is free with paid zoo admission. But visitors can deposit a coin to receive information on the insect's unique life cycle. The money is donated to projects that preserve butterfly habitat.

---

Butterfly facts

- Moths first appeared during the age of the dinosaurs, about 200 million years ago. Butterflies developed about 40 million years ago.

- About 20,000 species of butterflies inhabit the world. About 575 are seen in the continental United States. About 2,000 species live in Mexico.

- Butterflies range in size from 1/8 inch to a nearly 12 inches.

- Butterflies can see red, green and yellow.

- The top butterfly flight speed is 12 mph; some moths can fly 25 mph.

- No matter where you live in the U.S, about 100 species can be found near your home.

- Adult butterflies live up to a month.

- The monarch butterfly is the official state insect of Illinois.

SOURCES: http://www.thebutterflysite.com/facts.shtml and http://dnr.state.il.us

If you go

What: Butterflies at Miller Park Zoo, 1020 S. Morris Ave., Bloomington

Why: The exhibit has been cut from three months to one. July is the only month visitors may see them at the zoo.

When: Zoo is open from 9:30 a.m. to 4:30 p.m. daily; grounds close at 5 p.m.

Admission: $4.50 for adults; $3.50 for children ages 3-12 and seniors age 62 and older; children 2 and younger are free.

Information: Call (309) 434-2250 or visit www.cityblm.org/zoo