photo by: AP File

Monarch butterflies gather in Mexico during their winter migration in 2009.

The number of monarch butterflies spending the winter in Mexico has hit an all-time low, a Kansas University researcher says.

Chip Taylor, director of KU’s Monarch Watch program and a professor of ecology and evolutionary biology, said that poor weather conditions are mainly to blame for this year’s decrease, which continues a long trend of declining populations.

The butterfly colonies cover 1.92 hectares (about 4.75 acres), down from the previous reported low of 2.19 hectares reported in 2004. The colonies first became known to scientists in the mid-1970s.

Other factors continue to threaten monarch populations, including logging and the loss of their habitat from development, Taylor said.

If current trends continue, the complete extinction of the species would be unlikely, but this butterfly’s annual migration could be at risk, Taylor said.

“The migration is worth saving,” he said. “It’s one of the most significant biological events that goes on on this planet.”

If the monarch butterfly migration were to come to an end, the butterfly would still exist in isolated pockets, Taylor said. It has already spread to areas such as Hawaii, Australia and New Zealand.

People interested in saving the migration should plant new habitats for the butterfly to replace the ones being destroyed — something the Lawrence community does well, Taylor said. “We need to get that message out to the entire country,” he said.

Mary Olson, a Lawrence resident, said she keeps milkweed — the only plant monarch larvae will eat — in her garden to do her part in helping to save the butterflies.

“As a gardener, it’s kind of fun to plant a garden that’s really a buffet,” she said.

Taylor is now watching the weather in Mexico in hopes that potential storms do not bring the population down even further. Taylor said he thought even if the total area covered dropped to one hectare, the population could likely survive given previous experiences with weather-related disasters.