More monarch butterflies have overwintered in Mexican montane forests compared to the previous year, the Mexican Commission for Protected Areas recently reported.
Known as the Eastern Monarch population, Monarchs that winter in Mexico migrate north through Texas and the Southern Plains, through the Northern Plains, Illinois and the Midwest before moving on in the Great Lakes region.
Mexican officials reported a 35% increase in the forested area where the butterflies stayed. The population covered 7 acres of trees compared to 5.2 acres the previous year. The annual butterfly count does not measure the number of individual butterflies, but the area they cover when grouped together in trees.
Monarch expert David Zaya, a plant ecologist with the Illinois Natural History Survey, reported seeing his first monarchs of the season on May 25. Earlier, Zaya predicted the first monarchs would start arriving in Illinois in late May.
“The number of monarch butterflies that overwinter each year should be viewed with an eye to the recent past. Not only should we be looking at this year’s 2.8 hectares (7 acres), but also the trends of the past 10 years or so,” Zaya told FarmWeek.
“What I take away from reports from Michoacán (Mexico) is that the number of monarchs this year is ‘average’ for the last seven years – actually the median, not exactly the average,” Zaya continued.
“If we are hit with another extreme year like 2012, or even worse two extreme years, the species could be on the brink of extinction. For this reason, conservation efforts along the migration route and particularly here in their summer breeding grounds are of urgent importance,” he said.
Illinoisans can support monarch butterflies by planting flowers, such as coneflowers and black-eyed Susans, for adult butterflies. Their larvae are dependent on milkweed and grow only on plants of the milkweed family.
In Zaya’s view, farmers and rural landowners have the opportunity to make an impact through the Conservation Reserve Program (CRP) and other large-scale conservation programs, which he described as ” game changers for pollinator conservation in Illinois”.
“The CRP and other programs like it are going to have a huge impact on the conservation of pollinators and other creatures in Illinois,” he continued. “When you create a habitat for monarchs and other pollinators, it helps larger flora and fauna.”
According to the Associated Press, experts have predicted that the monarch’s increase this year may reflect the butterflies’ ability to adapt to more extreme heat or drought events by varying the date they leave Mexico.
Traditionally, monarchs arrive in Mexican forests in early November and depart for the United States in March.
Last year the butterflies left in February and escaped the heat and drought just north of the border in April and May. This year they stayed later until April.
Next year’s figures could reflect whether the delay proves beneficial, according to a spokesman for the government commission.
Monarch butterflies west of the Rocky Mountains overwinter on the California coast. This year, their numbers have rebounded to over 250,000 butterflies.
This story was distributed as a cooperative project between the Illinois Farm Bureau and the Illinois Press Association. For more food and agriculture news, visit FarmWeekNow.com.