Overwintering Monarch Population Second Lowest on Record

monarch lowest record

The numbers of migratory eastern monarch butterflies overwintering in Mexico fell nearly 60% since last year, reaching the second lowest level since the beginning of recordkeeping in 1994.

The butterflies occupied just nine-tenths of a hectare, down from 2.21 hectares in the winter of 2022-23. The lowest area on record was 0.67 hectares, in 2013-14.

According to Monarch Watch, this decline is so steep that it is likely to reduce the number of monarch sightings in the U.S. and Canada this coming summer.

“Monarch numbers are at a near all-time low because of drought conditions last fall that extended from Oklahoma deep into central Mexico,” said Chip Taylor, Monarch Watch Founding Director.

“Droughts reduce flowering and therefore nectar production, and monarchs need the sugars in nectar to fuel the migration and to develop the fat reserves that get them through the winter.”

However, while acknowledging that the decline is concerning, Taylor also points out that monarchs have been through similar declines in the past, and the population has subsequently rebounded.

“The numbers have been low many times in the past and have recovered, and they will again,” Taylor says. “Monarchs are resilient.”

Meanwhile, efforts to support the monarchs at this end of their migratory route are more needed than ever. “To recover, monarchs will need an abundance of milkweeds and nectar sources,” says Monarch Watch Director Kristen Baum. “We need to get more milkweed and nectar plants in the ground, and we all need to contribute to this effort.”

The Kerr Center website offers abundant resources for people wishing to plant milkweed and other native pollinator plants, including the guide, Native Milkweeds of Oklahoma.

monarch butterfliesPollinators

Sign Up for Our Newsletter