LAWRENCE, Kan. – If you plan on spending time outside this summer, Monarch Watch is looking for your help with its Calendar Project. Program officials are especially interested in learning more because monarch numbers in Mexico plunged to the second lowest on record this winter.

Monarch Watch is an education, conservation, and research program based at the University of Kansas. Officials are seeking the immediate assistance of hundreds of monarch enthusiasts (community scientists) in collecting observations of adult monarchs in their area during 2024 for their Calendar Project.

“If we have people who are interested who spend some of their time outside every day, they could send in their reports on whether or not they observed monarchs. That would be excellent information that would inform where the population is this year,” said Kristen Baum, director of Monarch Watch.

“Knowing when people didn’t see monarchs is also good information,” she said. “Sometimes people get discouraged because they don’t see any but that’s good information as well for this year in particular when we want to know what is happening with the population.”

Authorities in Mexico City recently announced that the size of the eastern monarch butterfly population that overwinters in Mexico this year is the second smallest on record. The numbers are so low that few monarchs will be seen this coming summer in many parts of the United States and Canada.

What caused the population to drop? There have been challenges over time related to habitat availability and other factors, but researchers think it was the drought conditions this fall that caused the population plunge, Baum said.

“This fall drought conditions were starting in southern Oklahoma down through Texas, through northern Mexico, and all the way to the overwintering sites in Central Mexico,” she said. “The drought extended pretty consistently throughout the southern portion of their migration route.”

The year 2019 was a drought year as well. It was dry in Texas and northern Mexico but as the monarchs moved closer to the overwintering sites there were places with nectaring sites available, Baum explained. But this year there was such a consistent stretch of drought that it made it difficult to find nectar.

Experts think that because the condition of the monarchs was probably not great, the ones that did make it may not have had the necessary fat stores. That makes it even more important to know what they look like when they’re coming back through this spring. Some monarchs have already been observed in Texas.

“Some have left already so they will be headed back to Texas a little earlier than usual,” Baum said. “Most insects have this strategy where they lay a lot of eggs knowing that few will survive, depending on whether it’s a good year, good conditions, they make up lost ground pretty quickly.

“The challenge with monarchs, the fluctuations on the lower end are getting lower,” she explained. “You’re not seeing the highs as high but you’re seeing the lows more consistently low. So, it is this downward trend.”

The news of the low population is a shock to all who follow monarchs, said Dr. Orley “Chip” Taylor, who started Monarch Watch in 1992. The implications for the future of monarch migration are a concern.

“However, populations have been low in the past,” he said. “This count does not signal the end of the monarch migration.”

Taylor started Monarch Watch primarily for tagging monarchs. He was interested in the research questions related to tagging. Over time the programs expanded. The Waystation Program that encouraged people to plant milkweed and other native plants and then register their sites began in 2005.

“At the end of last year we had over 46,000 monarch waystations registered,” Baum said. “We’re hoping to pass that landmark this year. In 2013, Chip started the milkweed distribution program. At the time it was hard to find native plants and in particular native milkweed. We now have the free milkweed for large-scale restoration projects and also the free milkweed for schools and nonprofits.”

For information on how to sign up for the Calendar Project and to learn more about Monarch Watch, visit monarchwatch.org.