Monarch butterflies usually leave every winter. But this year, they’ve found a home at Suzanne Middle School in Walnut.

“I’ve never seen them stay over winter before, so I contacted the Western Monarch Initiative,” explained social studies teacher Alan Haskvitz.

This piqued the interest of researchers at Cal Poly San Luis Obispo.

“I was particularly interested in seeing that you observe monarchs breeding in the winter!” wrote Professor Francis Villablanca. “Wow, that is interesting!”

The associate chair of Cal Poly’s biological sciences department is collaborating with a team from the University of Georgia. They are studying monarchs that breed during the winter in California.

“We’re particularly interested in the disease levels these U.S. monarchs experience due to the protozoan parasite Ophryocystis elektroscirrha (OE),” Villablanca wrote in an email.

Monarchs infested with the parasite have a lower survival rate, smaller body size and shorter lifespan. Infected butterflies also show lower flight performance, including shorter duration and slower flight speed.

The monarch is the only butterfly that makes a two-way migration like birds do, according to the US Forest Service. It notes that while other butterflies overwinter as larvae, pupae or even adults, monarchs cannot survive cold winters.

Taking clues from the environment, the monarchs know when to head south for the winter. Combining air currents and thermals, they can fly as far as 3,000 miles.

The US Forest Service said monarchs living west of the Rockies overwinter in California along the Pacific coast near Santa Cruz and San Diego. There, monarchs roost in eucalyptus, Monterey pines and Monterey cypresses.

“Now my students are participating in a university study looking into the relationship between a parasite and the winter breeding of monarch butterflies,” Haskvitz said.

 

About two dozen students canvas the Walnut Valley campus, looking for the colorful orange butterflies. The kids look for monarch caterpillars and pupa, as well as the adult butterflies.

“Unfortunately, a lot of the butterflies die from the disease, so we send them to the university for testing,” said 13-year-old Rachel Lee. She is one of a group of eighth-graders working on the project.

Classmate Fitty Liu wants to study life science in college. The 13-year-old wonders why the monarchs aren’t migrating.

“I asked an expert and he said they should be migrating to Mexico,” Liu said.

Classmate Joyce Zhou, 13, explained how they tag a monarch.

“We have a procedure where we put an ID number on a butterfly to follow its progress,” Zhou said.

Suzanne Middle School built a butterfly garden with money from the Community Club and Walnut Valley Education Foundation. It also has a drought resistant garden thanks to the Walnut Valley Water District.

“The latest count was more than 20 caterpillars, which has depleted the available food supply,” warned Haskvitz. “The school is asking readers to consider donating milkweed plants to help, as the students expand the garden to the meet the needs of the growing population.”

Students look for caterpillars in the butterfly garden, where they raise Monarchs in all stages at Suzanne Middle School in Walnut on Tuesday, Jan. 14, 2014. Students are working with researchers at Cal Poly San Luis Obispo to study Monarch butterflies to see why they're not migrating. (Photo by Watchara Phomicinda/SGV Tribune)

A pile of dead Monarch butterflies found by students inside a classroom at Suzanne Middle School in Walnut on Tuesday, Jan. 14, 2014. Students are working with researchers at Cal Poly San Luis Obispo to study Monarch butterflies to see why they're not migrating. (Photo by Watchara Phomicinda/SGV Tribune)

Student Airi Gonzalez, 13, holds a caterpillar in the butterfly garden, where students raise Monarchs in all stages at Suzanne Middle School in Walnut on Tuesday, Jan. 14, 2014. Students are working with researchers at Cal Poly San Luis Obispo to study Monarch butterflies to see why they're not migrating.